Veterinary College, Bengaluru Monthly e-Bulletin
Newsletter Date : 31st August 2017
Volume No: 06 Issue: 08
Raveendra Hegde, Shivashankar B. P, Giridhara P and S. M. Byregowda Institute of Animal Health and Veterinary Biologicals, Hebbal, KVAFSU, Bengaluru e-mail: ravihegde63@gmail.com Porcine reproductive and respiratory syndrome (PRRS) is an economically significant disease impacting pig production worldwide. PRRS is an acronym (porcine reproductive and respiratory syndrome) for a viral disease characterized by two overlapping clinical presentations, reproductive impairment or failure in breeding animals and respiratory disease in pigs of any age. Etiology: The PRRS is caused by PRRS virus, an enveloped RNA virus in the genus Arterivirus, classified in the virus family Arteriviridae of the order Nidovirales. PRRSV is differentiated into two genetically distinct genotypes. Type 1 or European genotype (prototype Lelystad virus) with a predominant spread on the European continent and Type 2 (represented by VR 2332) or North American genotype that is mostly isolated on the American continent (North and South), as well as in Asia. A variant of genotype 2 is the cause of severe disease in Asia. The outbreak caused in China in the year 2006 was due to the highly pathogenic variant of type 2, hence the disease in Asia is caused by variant of genotype 2. Strains of PRRSV vary markedly in virulence. Susceptible species: The pig (Sus scrofa), whether domestic or feral, is the only species known to be naturally susceptible to this disease. Other species of wild pig and members of family Suidae may be susceptible. Geographical distribution: PRRS was first recognised in North America in the mid to late 1980s and spread rapidly throughout the world. In Europe, a similar disease caused by a distinct genotype of the virus also spread rapidly in that region during 1990–92. The disease is now present throughout the world, with the exception of Australia, New Zealand, Finland, Norway, Sweden, and Switzerland. In India, the disease was first reported in the year 2013 from Mizoram state and the disease has established as an epizootic disease in pig population of Mizoram. The disease has been reported from Kerala state and recently from Karnataka affecting swine population. Epidemiology and viral characteristics: Although the etiologic agent of PRRS has only recently been identified, much information has been published concerning its viral characteristics and epidemiology. The primary mode of transmission is the infected pig. PRRS virus has been detected in saliva, faeces, urine, milk and colostrum of infected animals. The virus persists in infected animals for a long time. Virus has been isolated from tonsillar tissue for up to 157 days post challenge exposure, while
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shedding has been documented for up to 99 days post infection. Transmission by semen, both via natural service and artificial insemination can occur. The virus can be transmitted via fresh and diluted semen and infected boars can become long-term carriers of the virus. PRRS viral RNA has been detected in semen for up to 93 days post challenge using polymerase chain reaction. Pig-to-pig transmission is the most important means of virus spread hence can spread rapidly through intensive pig-rearing regions. Significant risk factors for spread between farms include proximity to infected neighbouring herds, purchase of animals from herds incubating infection, and the purchase of semen from boars at PRRS-infected AI centres. Transmission of PRRSV to pigs fed infected pig meat has been experimentally reproduced. Mechanical transport and transmission has been reported via contaminated needles, fomites (boots and coveralls), farm personnel (hands), transport vehicles (contaminated trailers), and insects (houseflies and mosquitoes). Airborne spread of the virus has been experimentally documented out to 120m under specific meteorological conditions, i.e. prevailing winds. The environmental stability of PRRSV is poor. The virus is readily inactivated by heat and chemical disinfection (chloroform, ether, formaldehyde, and phenols). Infectivity has been shown to be greatly reduced (>90%) after exposure to pH levels <5 and >7. The PRRSV survives for only a short time on non-living substances (fomites). Pathogenesis: The PRRS virus compromises the cellular immune response and damages mucosal surfaces and has tropism for macrophages. Primary virus replication takes place in local macrophages from where the virus rapidly spreads to lymphoid organs and lungs. PRRS virus antigen has been found in the resident macrophages of a variety of tissues, as well as in other cells, including muscle tissues. Infection can occur via the respiratory, oral and venereal routes, as well as intramuscular, intraperitoneal or intravenous inoculation. Clinical signs: The clinical signs of PRRS vary with the strain of virus, the immune status of the herd and management factors. The incubation period ranges from 3-37 days. Infection may be asymptomatic. Porcine reproductive and respiratory syndrome virus (PRRSV) occurs in all age groups. Dermatological signs: There may be a reddish to blue discolouration and blotching of the skin, most often of the ears (which gives PRRS the name of ‘Blue ear disease’) and the vulva, and may also include the trunk of the infected pigs. Subcutaneous oedema of the rear limbs and, in neonates, of the eyelids and periorbital area, cranium and snout, may also be present, especially with the European genotype of PRRSV. Reproductive failure in sows: The disease is first characterized by acute illness with lethargy and reduced appetite, and spreads quickly through a herd over 7–10 days. Clinical signs are infertility, agalactia, lowered farrowing rates, a marked increase in late term abortions and stillborn, mummified or weak live born piglets. Respiratory disease may also be present. Sows can transplacentally transmit PRRSV to their unborn piglets. Respiratory disease in piglets and grower pigs: In piglets that survive the pregnancy and neonatal phases, PRRS manifests as respiratory disease and is often complicated by secondary infections. Concurrent infection with Pasteurella multocida, Porcine Circovirus Type 2 (PCV2), Mycoplasma hyopneumonia, Streptococcus suis, Salmonella cholerasuis, Haemophilus parasuis and swine influenza
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virus is common. High death rates can be observed, typically 30-50 percent in young piglets and 4-20 percent in post-weaning pigs. In post-weaning and grower pigs, clinical signs include dyspnoea, anorexia, lethargy, cutaneous hyperaemia, rough hair coats, and decreased weight gain. Secondary infections are common. Older pigs might show only minor respiratory signs. Subclinical infection often occurs in finishing pigs, boars, gilts, and sows; in some herds, infection is generally asymptomatic Gross lesions PRRS virus produces a multi-systemic infection in pigs, but gross lesions are usually only observed in skin, respiratory and lymphoid tissues. Interstitial pneumonia and enlarged lymph nodes can occur in all ages of swine, but most commonly observed in neonatal and young, weaned piglets. With severe disease, lungs are mottled, tan and red, and fail to collapse; the cranioventral lobes tend to be most affected. Lymph nodes are enlarged, sometimes haemorrhagic, and can range from solid to polycystic. Diagnosis and Treatment Clinical diagnosis: diagnosis of PRRS should be based on clinical signs and post-mortem examination, in conjunction with laboratory tests. The disease should be suspected with reproductive failure, high levels of neonatal mortality and respiratory problems in pigs of any age. Laboratory tests: The live virus should be handled in a minimum of animal biosafety level 3 laboratories. Any tentative clinical diagnosis should be confirmed by detection of the PRRS virus. This can be by virus isolation (VI), detection of PRRS antigen by fluorescent antibody tests (FAT) or immunohistochemistry (IHC) or detection of PRRS virus genome by polymerase chain reaction (PCR) and be coupled with presence of typical lesions. Serology provides indirect evidence of infection but does not determine if there is actual disease caused by PRRS virus. Specimens required: The following specimens should be collected. For virus isolation and RT-PCR: Virus isolation is difficult but can be attempted from buffy coat, serum, ascitic fluid, and tissues (lung, tonsils, lymph nodes and spleen). PRRSV is best cultured on porcine alveolar macrophages and MARC-145 cells. For antibody testing (serology) : Serum from up to 20 exposed animals in the herd. Specimens should be chilled and forwarded unfrozen on water ice or with frozen gel packs. Serological tests The enzyme-linked immunosorbent assay (ELISA) has the advantage of being able to test a large number of samples within a short period of time and has been developed to distinguish between the American and European types. The European antigenic type can also be detected with the immunoperoxidase monolayer assay (IPMA), using alveolar macrophages and the American type with the indirect immunofluorescence assay (IFA), using MARC-145 cells. Treatment: There is no specific treatment for PRRS. Treatment can be symptomatic and aim to prevent secondary bacterial infections.
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Differential diagnosis: The following diseases should be considered within the differential diagnosis of PRRS:
Reproductive disease Classical swine fever African swine fever Leptospirosis Porcine parvovirus Porcine enterovirus Haemagglutinating encephalomyelitis virus Aujeszky’s disease Toxoplasma gondi
Respiratory and post weaning disease Swine influenza Enzootic pneumonia Proliferative and necrotising pneumonia Haemophilus parasuis infection Porcine respiratory coronavirus Haemagglutinating encephalomyelitis virus Syncitial pneumonia and myocarditis Porcine circovirus-associated disease Nipah virus infection
Prevention: The most important strategy and not a disease specific prevention method is the application of basic bio security measures. Reducing the opportunities for virus introduction through animal segregation, increased hygiene for visitors, application of animal quarantine for pigs entering a herd and appropriate cleaning and disinfection at critical production stages will effectively contribute to the prevention of disease introduction. Additionally, both attenuated live and inactivated vaccines are commercially available, but it is important to match the genotype of the vaccine with that circulating in the pig population. While vaccination of pigs does not prevent PRRSV infection, it may reduce clinical disease and transmission of the wild-type virus. It is important to note that the modified-live vaccine virus can persist in pigs and be disseminated through semen and oral fluids; it should therefore not be used in naïve herds, pregnant sows or breeding gilts and boars. Furthermore, there is a potential risk that vaccinal virus can revert to a more virulent form and cause disease. Control: There is no single successful strategy for control of PRRS, largely because of genetic and antigenic variability between viruses, large swine populations and unresolved issues of transmission. Intervention strategies to prevent PRRSV spread are the keys to success. In some smaller herds, immunity may be sufficient so that infection is not causing significant economic losses, in which case no intervention is necessary. Once the disease is confirmed, a strategy should be decided either to eliminate the disease or to control (or “live with”) PRRS. Current control measures include the management of incoming replacement gilts, the use of vaccines and implementation of bio security protocols validated to reduce the risk of PRRSV spread within and between herds. In case the disease breaks out in a farm, depopulation with subsequent cleaning and disinfection and proper disposal of the carcasses has to be used to eliminate the infection. Socio-economic impact: PRRS is considered to be the most economically important viral disease of intensive swine farms in Asia, Europe and North America. Financial losses are mainly due to increased death loss, poor
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reproductive performance and increased use of vaccines and medications. Secondary diseases following a PRRS outbreak on a farm can lead to additional costs. Furthermore, diagnostic testing and herd monitoring after a PRRSV introduction are necessary in order to develop comprehensive control or eradication strategies, but at the same time these activities are costly. PRRS has been estimated to cost approximately USD 560.32 million in losses for United States (USA) swine producers each year. The highly virulent PRRS outbreak in China and Viet Nam caused extensive losses and an enormous rise in pork prices. In general, socio-economic assessments of PRRS and pig diseases in developing countries are not really abundant. Socio-economic assessments of PRRS in the swine industry and smallholders in India have not been carried out. Trade restrictions for countries with endemic PRRS and/or outbreaks do not exist. However, the disease is notifiable to the World Organisation for Animal Health (OIE).
Kamal Hasan, Rathnamma D, Dhanalakshmi S, Chandrashekar G KVAFSU Bidar. e -mail: kamalmicrobiology@gmail.com The microbiological examination of clinical samples is required to establish the etiology and line of treatment to be followed through antibacterial sensitivity testing. It is very important to a veterinarian that he should go for antibacterial test before start of treatment with an appropriate antibacterial drugs. In such cases, one should follow the treatment after collecting the samples for laboratory examination while simultaneously antibacterial sensitivity testing is done and results are utilized to allow a further line of treatments. Direct examination of samples: Direct examination of specimens reveals gross pathology. Microscopy may identify microorganisms. Immunofluorescence, immuno-peroxidase staining and other immunoassays may detect specific microbial antigens. Genetic probes identify genus- or species-specific DNA or RNA sequences. Culture: Isolation of infectious agents frequently requires specialized growth media. Nonselective (noninhibitory) media permit the growth of many microorganisms. Selective media contain inhibitory substances that permit the isolation of specific types of microorganisms. Microbial Identification: Colony and cellular morphology may permit preliminary identification. Growth characteristics under various conditions, utilization of carbohydrates and other substrates, enzymatic activity, immunoassays and genetic probes are also used. Serodiagnosis: A high or rising titer of specific IgG antibodies or the presence of specific IgM antibodies may suggest or confirm a diagnosis. Antimicrobial Susceptibility: Microorganisms, particularly bacteria, are tested in vitro to determine whether they are susceptible to antimicrobial agents and it is helpful to treat the animals. Collection of specimens in Bacterial Diseases: 1. Haemorrhagic Septicemia: From sick animals fixed smears from blood and throat swelling and smears from heart blood and liver, heart blood in a sterile syringe/tube, lymph nodes and spleen from dead animals are collected. 2. Anthrax: Thick blood smear, blood or a piece of ear in boric acid. It is not advisable to open the carcass suspected for anthrax in field. If opened, it should be properly disposed off by burning. All natural orifices
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of dead animals as well all bleeding surfaces may be sealed with cotton soaked in carbolic acid. 3. Black quarter: Impression smears from affected muscle tissues, exudates from lesions, pieces of affected muscles on ice. 4. Enterotoxaemia & Lamb dysentery: Contents of small intestine with or without chloroform separately on ice, kidney, urine. 5. Brucellosis: Paired serum, heart blood and abomasal contents of aborted fetus, placenta with 2-3 cotyledons, vaginal swabs in phosphate buffer saline, in separate containers on ice, whole fetus, if small, on ice. Neat semen in sterile vial or semen straw on ice. 6. Bovine genital campylobacteriosis: In males, preputial mucus/ secretions/ washings. In females, vaginal mucus /lavage, aborted fetus, placenta, stomach contents, lungs, liver etc. 7. Johneâ&#x20AC;&#x2122;s disease: Rectal pinch smears, bowel washings. In dead animals terminal portion of ileum with ileo- caecal valve, mesenteric lymph nodes. 8. Glanders: Exudates from abscesses and lung lesions in vials on ice. Impression smears from exudates duly fixed. 9. Tuberculosis: Nasal discharges in sterile container from live animal, sample of milk in sterile containers, tissue pieces from suspected lesions in 10% neutral formal saline solution , smears from lesions fixed by heat, lymph glands, lung lesions in sterile container for bacterial isolation in 50% buffered glycerin. 10. Leptospirosis: Blood, serum, pieces of liver and kidney in 10% neutral formal saline solution, milk, mid stream urine (20 ml) in sterile vials by adding 1 drop of formalin. 11. Salmonellosis: Intestinal swab, heart blood, bile, liver, spleen etc. in sterile container on ice. 12. Actinomycosis & Actinobacillosis: Smears from pus lesions, pus in vial on ice, formalin preserved materials from affected muscles. 13. Listeriosis: Aborted fetus, brain, placenta, and all internal organs in sterile vials on ice and in 10% neutral formal saline solution. 14. Mycoplasmosis/CCPP/CBPP/Coryza: Swabs from lesions, nose and vagina in phosphate buffer saline on ice and in 10% neutral formal saline solution for histopathological examination and on ice, separately and paired serum. 15. Chlamydiosis/Psittacosis: Nasal swab, lung pieces in sterile container on ice and internal organs in 10% neutral formal saline solution, fixed impression smears from liver, lung and fetus, sterile paired sera. 16. Contagious equine metritis: Urogenital swabs from mare and stallion, paired serum samples. Collection of specimens in viral diseases 1. Foot and mouth disease: Vesicular fluid from unruptured oral vesicles and curetted epithelium from fresh lesions oeso-pharyngeal fluid in 50% phosphate buffered glycerin preferably on ice. About 10 ml blood in EDTA/Heparin. Pieces of heart and other organs in calves in 10% neutral formal saline solution and ice, separately. 2. PPR: Eye, mouth and rectal swabs in phosphate buffer saline on ice, about 10 ml or more blood in anticoagulant, pre-scapular lymph nodes, spleen(20-30 g), pieces of intestine, on ice, lung, liver, spleen, tonsils etc in 10% neutral formal saline solution. Tissue materials from 5 to 6 or more animals be collected
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and dispatched for better picture of disease/outbreak. Cotton buds can be used as swabs. 3. Bovine spongiform encephalopathy: Tissues from brain stem involving medulla oblongata, posterior cerebellar peduncle, rostral quadrigemina body and spinal cord in 10% formalin saline for histopathological examination and for prion detection very thin pieces of above site of brain in frozen state. 4. Bovine viral diarrhea/Mucosal disease: Blood in EDTA, pared serum samples, semen, intestinal swabs, lymph nodes and spleen on ice. 5. Malignant catarrhal fever: Blood in EDTA, paired serum samples, all internal organs including cornea, skin, muzzle in 10% formal saline. 6. Rabies: Portion of brain with cerebellum, brain stem, salivary gland in 50% phosphate buffered glycerin or glycerin saline in leak proof hard box and the rest half portion in 10% neutral formal saline solution. Alternative and preferable small pieces from hippocampus and brain (cerebellum, medulla, cerebrum, spinal cord) in 50% buffered glycerin and in 10 % neutral formal saline solution separately duly sealed, and packed in thick poly bags and hard box labelled “ Suspected for rabies” . If available, fresh smears from brain may be stained with Seller’s stain. All personnel attending postmortem should be vaccinated against rabies. 7. Pox disease: (Sheep, Goat, cow, buffalo etc): Scabs in sterile containers on ice, scabs in 50% buffered glycerin, skin lesions in 10 % neutral formal saline solution separately. 8. Bovine herpes virus1,2,3/IBR/IPV, Bovine mammilitis/Parainflunza3/Adenovirus infections: Paired serum ( sterile) on ice, swabs from vaginal and nasal lesions and pieces of trachea, lung in transport medium on ice and smears and pieces of trachea, liver, turbinate bone, lung in Bouin’s fixative 10 % neutral formal saline solution. From bulls semen and preputial washing in transport media and paired serum on ice. 9. Enzootic bovine leukosis: Blood in EDTA, tumour tissues, lymph nodes, abomasums, right auricle of heart, spleen, intestine, liver, kidney, lung and uterus. 10. African swine fever: Blood in EDTA, spleen, tonsil, kidney, lymph nodes, bones on ice for virus isolation, paired serum samples. 11. Transmissible gastro-enteritis (TGE): Feces, small intestine, lung, udder on ice for virus isolation and paired serum samples. 12. Aujeszky’s disease (Pseudo-rabies): One half of brain , skin and subcutaneous tissues in sterile container on wet ice or in buffer glycerin for virus isolation. Other half of brain , spinal cord, liver, kidney, spleen, mesenteric lymph node fixed in 10% neutral formal saline solution or Bouin’s fixative for histopathology and inclusion body demonstration. Paired serum samples are also to be sent. 13. Bluetongue disease: Blood during peak of body temperature in heparin (10units/ml) or EDTA paired sera in sterile containers on ice. About 10 ml blood and 2 ml serum having antibiotic or merthiolate may be collected on ice. Spleen, lymph nodes (5- 10g) on ice for virus isolation, spleen. Pieces of sternal muscles lymph nodes, intestine, internal organs etc. in 10% neutral formal saline solution for histopathology be collected for differential diagnosis of other diseases. 14. Rift valley fever: Blood (5ml), liver (5g), spleen, brain, aborted fetus on ice for virus isolation, liver, spleen, lung, peripheral lymph nodes in 10% formal saline for histopathology.
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15. Caprine arthritis encephalitis/ Maedi/ Visna disease: Paired serum, joint capsule, lung, Brain etc. on ice and in 10% neutral formal saline solution. 16. Canine distemper: Pieces of lung, urinary bladder, liver, trachea, stomach wall, brain etc. in 10% formal saline, impression smears from liver, pieces of liver and spleen on ice. 17. Infectious canine hepatitis: Liver, gall bladder and kidney in 10% neutral formal saline solution. Impression smears from liver fixed in methanol. Spleen and liver in sterile containers on ice. 18. Canine parvoviral disease: Rectal swabs and feces in phosphate buffer saline, pieces of intestine, heart on ice, all internal organs in 10% neutral formal saline solution. 19. Equine influenza: Nasal swabs in phosphate buffer saline or on ice, paired serum. 20. Equine infectious anemia: Paired serum, all internal organs, paired serum. 21. African horse sickness: 20 ml unclotted whole blood in EDTA, paired serum samples, spleen, brain, lung in 50% buffered glycerin and 10% formal saline separately. Collection of Materials in Toxicosis/Poisonings Animals suspected for poisonings be thoroughly autopsied and all internal organs may be collected in formalin and sterile containers, separately to eliminate infectious causes of death. Aflatoxicosis: Suspected feed (specially ground nut cake, about 100gm. Each), pieces of liver( 50 g), spleen in 10% formal saline and on ice, separately. Poisoning cases: Stomach and intestinal contents (100g) on ice, left over fodder(100g) and about 100gm liver pieces in alcohol on ice. Forage poisonings: Samples of grass/fodder, plants, liver and stomach contents on ice. Collection of specimens in other conditions Mastitis: Milk samples (5ml) in sterile tubes on ice. Abortion: Whole fetus on ice or all internal organ, vaginal swab in phosphate buffer saline, pieces of placenta in sterile containers on ice and in 10% formal saline solution separately, paired serum. Infertility: Sterile semen, preputial swab and paired serum on ice. Pyrexia of unknown origin: Blood smears, blood in EDTA and paired blood/serum on ice. Mycotic infections: Deep skin scrapings in sterile vials for fungus isolation. Transportation of specimens to Diagnostic laboratory Taluka level : Primary Health care centre / Primary veterinary dispensary may not be having sophisticated diagnostic instruments but, initial screening , routine diagnosis can be done. Farmers should be trained in case of any disease outbreaks to send the clinical samples to nearest diagnostic laboratory, or to report to higher authorities. District level : Regional diagnostic laboratories / District diagnostic laboratories with trained scientists/ technical personnel are available for disease investigation, to take care of disease outbreaks, seromonitoring in vaccinated animals and keeping records of source of outbreak. State level/ National level : Each state is having AH & VS Diagnostic laboratory and in turn vaccine production and research institute/ Animal disease investigating unit/ AICRP unit/SRDDL/Central reference diagnostic laboratory/ North eastern reference diagnostic laboratory. All these units should train farm personnel/ veterinarians/technical personnel to identify and send the clinical samples to near by diagnostic laboratories.
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Kamal Hasan, Rathnamma D, Dhanalakshmi S, Chandrashekar. G KVAFSU Bidar. e - mail: kamalmicrobiology@gmail.com Control of disease: It is the reduction of the morbidity & mortality from disease & it is a general term embracing all measures intended to interfere with the unrestrained occurrence of disease whatever its cause. Control can be achieved by treating diseased animals, which therefore reduces disease prevalence & by preventing disease, which therefore reduces both prevalence & incidence. Eradication of disease: It refers to the regional extinction of an infectious agent. Ex: Foot and Mouth disease in UK, Rinder pest from globe Strategies of disease control and eradication: 1. Doing Nothing: Here no control measures are undertaken but the occurrence of a disease is reduced or absent, this may be due to the natural history of a disease & also due to host parasite relationship. Ex: In Cyprus – Blue tongue disease is not present in the winter season because the vector culicoides midges are not available or low in numbers during winter 2. Quarantine measures: Isolation of the infected animals or the animals at high risk of disease or in animals found to be in carrier state of a particular infective agent. Quarantine measures are undertaken in following conditions: When animals are infected with some disease When animals are at high risk during outbreaks When animals are imported. Generally 30-90 days by quarantine authorities. The etiological agent if present in these animals is prevented entry from one country to another. 3. Prophylactic measures: It is done through vaccinating the animals. Live/Attenuated vaccines Inactivated /killed vaccines Toxoid vaccines Modern/subunit vaccines 4. Therapeutic & prophylactic chemotherapy: Antibiotics, antihelminthics, hyper immune serum are used to treat diseases & some of the drugs are administered prophylactically at the times of high risk to prevent disease & thus to increase productivity. Ex: a) The pre-operative & post-operative use of antibiotics to prevent bacterial infections b) Addition of antibiotics to livestock feed to promote growth c) The use of coccidiostats in chicks to prevent the occurrence of coccidiosis. 5. Slaughter of animals: The productivity of animals usually is decreased when they are chronically infected. The affected animal can become a source of infection to other animals, in such circumstances it may be economically & technically correct to slaughter the affected animals. Eradication of specific diseases from herds often involves “Test & Removal “ strategy in which all animals are tested & only those animals testing positive are removed & slaughtered. Ex: - FMD in UK, Bovine Spongiform Encephalopathy, Animals infected with Rabies. 6. Movement of Hosts: It involves the migration of animals from areas with disease to areas without
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disease, usually during a particular season. Ex: Horses are moved at indoors at night to prevent infection with African Horse Sickness virus, which is transmitted by night flying vectors of the genus Culicoides midges. 7. Mixed, alternate, & sequential grazing: It is done to prevent the occurrence of a disease to reduce the incidence of a disease. 8. Control of vectors: Vectors play an important role in transmission of various infectious diseases. Total elimination of vectors is not possible, but some of the control measures can reduce the number of vectors that in turn reduces the occurrence of diseases. Spraying of insecticides has reduced the number of vectors. Apply of molluscicides to tanks & ponds having snails. Use of mosquito nets. Use of mosquito sprays. 9. Fomite disinfection: Fomites are non-living things, ex- cattle shed, feeding troughs, cracks & crevices, water, feed etc play an important role in transmission of diseases, so proper disinfection is necessary. Ex- phenols, iodophore preparations, chlorinating agents etc. 10. Niche filling (Ecological Interference): The presence of an organism in a niche can prevent its occupation by other similar organisms. Ex- Administration of suspension of endogenous internal microbes to day old chicks to prevent the colonization of gastrointestinal tract by virulent salmonella spp. 11. Improvement in environment & feeding: This is an important aspect in controlling a disease. For this purpose natural history of the disease should be studied properly & action should be taken against the factors involved in the occurrence of a disease. Various measures involved are as follows;
Proper management Feeding of balanced diet Avoiding of overcrowding Proper ventilation
Proper hygienic requirements Fresh water Regular vaccination Treatment of affected animals
12. Genetic selection: The genetic screening of animals is done by test mating, cytogenetic studies, & biochemical analysis. The genetically resistant animals are selected & bred, so that a particular population is resistant to a particular disease. Important factors to be considered in control & eradication programs are
Proper knowledge about transmission Cause of disease Etiological agent Host range, nature of host Host-parasite relationship. Veterinary infrastructures. Availability of proper vaccine. Diagnostic feasibility Adequate surveillance.
Availability of replacement stock Producers & society’s view Public health significance Existence of suitable legislation with provision for compensation Possible ecological consequences Economic costs Availability of funds for the program
Logistic problems & vaccination failure: Loss of cold-chain maintenance of vaccine during transportation or storage of vaccine
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Non availability of man power for large scale vaccination programmes Adverse climatic conditions during transport of vaccine. Leakage & spillage of vaccine vials, vaccine containers, & storage equipments during transport of vaccine. Contamination of vaccine during transportation. Long term transport of vaccine may generate excessive heat in vaccine storage devices during transport making it ineffective.
Pragathi K.S, Vijayakumar B. Shettar, Rudresh B.H and Jayashree R. Department of Animal Genetics and Breeding, Veterinary College, Shivamogga. Email ID: pragatiksvet114@gmail.com A farmer may well know a lot about the animals he keeps. However, keeping the information in one’s memory is not reliable enough and may not be recalled exactly. Without an accurate idea of what is happening in the farm, farmers cannot make the best decisions that will lead to maximum profit. A combination of both high and efficient production is the key to a profitable dairy farming operation. For example farmer should know the daily milk production level in his farm because it determines the cost of production. They also need to know which male-female combination is producing the better producing offspring. Hence the record keeping is very crucial in dairy farm to optimize production and maximize the profit. Importance of record keeping 1. It gives the information about the reality of the farm in the concerned period. 2. Managemental control like Whether the activities are going according to plan Feed utilization trend Productivity status Vaccination, Treatment, Deworming regularity etc. 3. To know the parents of any individual – for the selection of better producing individual for future breeding purpose. 4. Provides the figures for farm planning and budgeting – planning for future by correcting the farm weakness etc. 5. Details of how much the producer/ farmer is yielding by maintaining particular number of cows. 6. By maintaining the proper inventory on farm operations, one can keep the track on assets. 7. To obtain the money for farm business operations from the bank. Characteristics of good record keeping systems The records should be simple, easy and quick to interpret. In all records, there should be a 'Remarks' column/ entry, explaining the reasons behind any unusual observation. This is very essential in interpreting the implications of the records, particularly for a third party who may have not been directly involved in taking the records, but needs to make informed/ accurate decisions.
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Efficient in terms of time and cost. Types of Records: The major types of records are Animal identification, Breeding, Production (Performance), Feeding, Health, Financial records Animal identification records: The needs are for an identification method that is cheap, not damaging to the animal and readable from a distance of at least 2-3 meters and by relatively long-lasting. The methods of identification can be subdivided into two categories: Permanent and non-permanent. Permanent Identification: Tattooing (ear), Description (diagrams, sketches and photographs), Ear-notching/ Punching, Branding (hot/ freeze branding). Non-Permanent identification: Tags (Ear-tags, Collars or neck straps (chains). The most common methods of marking cattle are ear tags and large ear tags are easier to read at a distance. The biggest problem with ear tags is that up to 20 percent get lost each year. Using a combination of plastic/ metal ear tags with branding/ double tagging maintain animal identity. Milk production and disposal records: Daily morning and evening milk yield (MY), total yield, peak yield (PY), lactation length (LL), date of drying (DOD), dry period (DP) etc. Breeding Records: The importance of breeding is to measure the productive efficiency of the herd and to enable culling and selection exercise to be carried out for breeding and genetic improvement. A good farmer would like a cow which gives a calf yearly. Therefore, an accurate breeding record of each individual cow which is up-to-date is needed. The important data in breeding records include: Pedigree/ parentage (Dam name, grand dam, sire name, grand sire etc) Growth (Date of birth (DOB), birth weight, date of weaning, weaning weight etc.) Fertility (Age at first service, age at first calving, date of calving (DOC), number of services per conception etc.) Feeding Records: This is difficult to estimate on farms where animals graze. These should indicate the amount of feed given as well as the type of feed. Feeding records should be used the most for day-to-day management, evaluating pasture management practices and for planning of activities in the future. Thus the important records are: Available fodder on farm Quantity fed – roughages/ concentrates/ minerals supplemented Spoilage (per batch) Health records: Health records are needed to take up the required vaccinations at the right time and to prevent epidemic/ endemic diseases. They also provide information about the health status of each individual animal and the whole herd. Vaccination/ Dipping/ spraying/ De-worming. Morbidity, mortality, signs and symptoms, diagnosis, treatments and Postmortem. Financial Records: The records of the expenditure and revenue should be kept for cash analysis and enterprise appraisal. Economic records are of paramount interest in providing the farmer with information concerning the profitability of his farm. Moreover they are of great help in decision making at the right time. For example, is it profitable to feed concentrates, is it advisable to apply for a loan or credit to invest in a machinery or technology, is it more economic to raise the calves with whole or skimmed milk? Answering these questions is only possible if adequate records are available. Moreover, for tax purposes and for getting loans or credit, economic records are required.
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Given below (Table 1 to Table 8) are some of the model formats of different types of records and they can be altered accordingly. Table 1. Monthly livestock register Date
Cows Milch
Heifers
Dry
Bulls
Calves
Bullocks
Males
Remarks
Females
Table 2. Roll call register Sl.No
Date
Opening Balance M
F
Birth/ Purchase T M
Grand Total
F
Sale/Cull
Death
Closing Balance
M
M
M
F
F
F
Remarks T
Where, M=male, F=female, T=total Table 3. Daily feed register Date
No. of Animals
Concentrates Received
Issued
Dry fodder Balance
Rec.
Iss.
Green fodder Bal.
Rec.
Iss.
Remarks
Bal.
Table 4. Growth record of young stock Calf No.
DOB
Weight at birth (kg)
Weight at weeks (kg)
1
2
3
4
5
6
7
8
9
Weight at first service (kg)
10
11
Weight at first calving (kg)
Remarks
12
Table 5. Breeding register Cow No.
DOB
First service D
Second Service
B No.
D
1st PT
Third Service
B No.
D
B No.
2nd PT
D
R
D
Exp. DOC
Actual DOC
Remarks
D P
Remarks
R
where, PT = pregnancy test, D= date, B= bull, R= results Table 6. Lactation record for individual cow Lactation No.
Sire No.
DO C
Sex of Calf
Total MY (kg)
LL (days)
PY (kg)
Days to reach PY
Avg. MY/ day
DO C
Table 7. Daily milk record Cow No. Time Date
Total A.M
P.M
A.M
P.M
A.M
P.M
A.M
Remarks P.M
Total
where, A.M=ante meridiem, P.M=post meridiem Table 8. Herd health register Date
Animal No.
History
Diagnosis
Treatment
Name of the Veterinarian
Result
Remarks
Conclusion: Records are essential in dairy farm to optimize production and maximize profit. In breeding programs, production records can assist in determining superior breeding stock. Thus the quality of record keeping practiced in a dairy farm determines success of the farm.
Pashubandha 2017 2014
Volume VolumeNo No::06 3 Issue : 08 01
Sasmita Panda1, Kuldeep Kumar Panigrahy2, C.Kotresh Prasad3 1 Ph.D. Scholar, Department of Livestock Production and Management, West Bengal University of Animal and Fishery Sciences, Kolkata. 2,3Ph.D. Scholar, Division of Livestock production management, ICAR-National Dairy Research Institute, Karnal, India. e - mail: ckprasad91@gmail.com Introduction: Culling is the process of rejecting unproductive and uneconomic birds from the poultry house which do not possess the qualities for giving enough benefit in return for their culture. Cull is a bird rejected for its inferiority or unproductiveness during rearing or at the end of laying cycle when the flock is liquidated. This is a significant aspect of poultry farming because an un-culled stock may give a serious setback to the farmer. Culling is a continuous operation throughout the year. Culling is advantageous because it helps in saving the feed, in preventing the spread of diseases and in bringing uniformity of the stock. Process of culling the poultry flock in an intelligent manner is of great importance for success in poultry keeping. The different advantages of culling are: Enhances the profit by ensuring that the feed will be consumed by the better producing hens and not by the poor producers which are kept at a loss. Helps in saving the flock of birds which are best suited for breeders on account of their better production as well as superior strength and viability. Provides more living space to the left over producing birds. Removes the risk of other birds catching a disease from the sick or injured one. Increases food and water space for the productive chickens. Increases the flock’s overall egg-per-hen ratio or per-bird average growth rate. The time of culling and kind of poultry to cull In a commercial layer farm, the culling of flock is done at 72 weeks where as in commercial broiler it is practiced at 6 weeks. The broiler/layer parent stocks are culled at 65 weeks of age. Culling should start with the eggs and never cease as long as chickens inhabit the farm. The age of both hens and pullets should also be considered. The crippled, wobbly, or weak chick should be destroyed soon after hatching. Scrawny, unpromising individuals should be eaten or sold and only the fittest are allowed to survive. It is obvious that it would be more profitable to eliminate the cull early in life, if that were possible, than to wait until later. Birds of low vigor, crow-headed, or have long rangey bodies, as well as slow maturing, off type individuals, should be culled before the pullets begin to lay. Culling and selecting the breeding males is equally important. Culling domestic poultry as well as ducks, turkeys, guinea pigs other than chickens have been given little attention. When to cull: Culling should be continuous throughout the year. Culling of chickens is done at every stage of their life. One day old chick if shows the tendency of drowsiness, inactivity and remains thinner than the fellow ones of the same breed should be culled. Growing chicks with a slow rate of growth of body and feathers or having a protruded breast or thin thigh muscles or a deformed body should be culled. Laying birds can be culled before they start laying eggs and after that, at every six months.
Pashubandha 2017 2014
Volume VolumeNo No::06 3 Issue : 08 01
Systematic culling, that is the handling and examining of every bird in the flock, should start about the middle of July and continue periodically about once a month until the middle of October. Systematic culling is not practical at other seasons of the year. Summer culling (July and August) is performed to eliminate the slacker hens where as September and October culling is practiced to observe and select the best individuals to reserve as future breeders. How to cull: A preliminary evaluation is done in the month of July or August to know the laying performance of a hen. Hens which are laying at this season of the year are usually kept as the price of eggs makes them profitable. If these are found to be medium producers at a later stage, they can be disposed off. The flock should be confined in the poultry house the day they are to be culled, or in the event if there is no house available, they should be taken from the roosts and cooped the night before. The culler should be able to determine three things; present production, persistence of production and intensity or rate of production. Judging present production: Present production may be determined by examining the vent, pubic bones, comb, wattles and earlobes. Vent - The vent of a laying hen is large, moist, and dilated, and tends to become oblong in shape. The lower edge appears flat and extends almost straight across, and the upper edge blends evenly into the surrounding tissue which has a smooth, loose, pliable appearance. In case of a cull or, non laying hen, the vent is generally dry, small, contracted and the region around the vent is puckered, rough, and hard. Pubic Bones- The pubic bones of a laying hen are two to three fingers apart, where as in a non producer, the width is of one or two fingers. Comb, Wattles, and Earlobes- Increased blood circulation to comb, wattles, and earlobes helps in development and functioning of the egg organs. These should be large, full and glossy in a laying hen. As the laying season advances the appendages of the head lose their gloss and prominence. Near the close of the production period, though still retaining their red color, they appear limp or wilted and reduced in size. The comb of a hen that has quit laying is small, contracted, dry and usually covered with a white scale or dandruff. If these structures are relatively cool to touch, it indicates that there is slight circulation of the egg organs. The comb is one of the best external characters to indicate nonproduction in hens. 2. Persistence in laying: With the progression of culling season, separation of cull from layers and gradation of layers is done. In early September the low producers that were passed in July and August because they were laying a few eggs should be disposed off. The early spring pullets are coming into production by this time and a part of the houses that have been occupied by the hens are needed for their accommodation. Color- Persistence in laying is determined by color and molting. The yellow pigment (xanthophyll) observed in the skin, beak and shank are transferred to yolk during laying. If this visible pigment is not continually renewed it fades, leaving the various parts white, or as commonly expressed, bleached called as depigmentation/ bleaching. When a yellow-skinned pullet begins to lay the color first fades from the vent, then eye ring, earlobes, followed by the lower and upper mandibles of the beak. The color leaves the corners of the mouth or base of the beak first, gradually fading towards the tips, disappearing from the arch of the upper mandible last. From 4 to 6 weeks of production will usually eliminate all color from the beak. The shanks are the last to lose their color. Normally, 4 to 5 months laying is necessary to
Pashubandha 2017 2014
Volume VolumeNo No::06 3 Issue : 08 01
completely bleach the shanks. When a hen stops laying the yellow color reappears in each of the above regions in the same order in which it disappeared, that is, in the vent, eyelids, lobes (if white), beak, and shanks, returning, however, much faster than it disappeared. Pigmentation observations should always be made in daylight, artificial light being unsatisfactory. The order of the most common breeds according to the rapidity with which the pigment fades are: Leghorns, Wyandottes, Plymouth Rocks and Rhode Island Reds. When culling white-skinned birds such as the Orpingtons, Sussex and Dorkings or the dark-shanked breeds such as the Langshans or Andalusians, no attention can be given to color changes. Birds of these breeds are judged by the molt. Table: Bleaching of Yellow Coloring Body part
Time after first egg
Vent
4-7 days
Eyering Earlobe Base of beak Tip of beak Bottom of feet Front of shank Bottom of shank hock
7-10 days 14-21days 4-6wk 6-8wk 8-10wk 15-18wk 20-24wk About 24wk
Molting- The normal physiological process of shedding of old feathers and replacing it by new ones is called molting. Particular order in which the feathers fall is head, neck, body (back, breast, and abdomen), wings and tail. Good layers are late and quick moulters, complete within 4-6 weeks and laying is continued with a slight drop. Bad layers are early and slow moulters , process takes 16-20 weeks and laying stops drastically. Primary feathers of wing drop before secondary feathers and 6 weeks required to grow primary feather. The new primary feathers make about two-thirds of their growth the first 3 weeks and one-third the last 3 weeks. 3. Rate of production: Rate or intensity of production and persistence in production are characteristic of the best layers. Hens may be laying and show no signs of molting but have a low rate of production, i.e., 2 to 3 eggs per week. In order to make a good record a hen must produce at a high rate, i.e., 5 to 6 eggs weekly, as well as for a long period. Breeders should be selected from high producers. Ovary and oviduct of a hen in full production is about 20 times as large as the same organs of a nonproductive hen. A depth of 4-5 fingers from the end of keel to pubic bone indicates good production. Good producing hens have thin, soft, oily, silky skin with a good and friendly temperament. They have large abdomen devoid of fat and are good eater with crop nearly always full. Types of culling: There are two different types of culling such as: ď&#x201A;ˇ Sight culling at the time of housing ď&#x201A;ˇ Culling by individual inspection, which evaluates the bird's ability to lay or her past productive performance
Pashubandha 2017 2014
Volume VolumeNo No::06 3 Issue : 08 01
Sight Culling- It removes undersized, underdeveloped, weak, crippled, or diseased birds which have very little chance of becoming good laying hens. The number of birds culled partly depends on the availability of space in the laying house. There should be removal of any bird which has a permanent genetic or injury-produced deformity such as crossed beak, slipped wing, one or both eyes blind, or any leg deformity that can interfere with the bird's ability to mate or to reach feed, water or the laying nest. Culling by Individual Inspection- In commercial egg laying operations the birds are not usually culled after being placed in the laying house unless the birds become diseased or crippled. In a small laying flock, culling is practiced eight to ten weeks after being placed in the laying house. This allows the birds plenty of time to adjust to their new surroundings and reach peak production as well as provides extra time for the development of the slower maturing pullets. The non-laying or poor producing birds can be detected by observing the condition of the comb and head characteristics. Culling at night is recommended. A flashlight with the lens covered with blue cellophane will make it easier to detect poor layers without disturbing the flock. The birds should be handled as little as possible so that production will not be greatly reduced. Culling should be delayed if a significant portion of the flock is suffering or recovering from a minor disease or molt. Culling a diseased or molting flock often removes some of the better laying birds. Table: characteristics of layer and non layer Character Comb and wattle
Layer Large, bright red, glossy
Non layer Small, dull, shriveled
Head Eye Eyering and beak vent Abdomen Pubic bone
Neat, refined Bright, prominent Bleached Large, moist, bleached Deep, soft, pliable Flexible, wide apart
Beefy, weak Dull, sunken Yellow tinted Small, dry, puckered, yellow Shallow, tough, tight Stiff, close together
Precautions to be observed during culling There is no particular rule regarding culling for all the flocks. Age of the hens to be culled should be given careful consideration. Judging should not solely depend on any one of the indications previously discussed as it will result in untold errors. No managemental problem should occur during the procedure. In culling for egg production, questionable hen should be given the benefit of doubt. Normal treatment should be given to all the birds. The birds to be culled should be caught with least amount of fright and disturbance by the help of a catching crate. Conclusion: “IT IS NOT THE NUMBER OF HENS THAT PAYS; IT IS THE KIND”. The whole process of culling should be completed very carefully as any error during culling may eliminate good hens. The birds should be given plenty of food, water and precautions should be taken to avoid upsetting the hens and affecting their normal rate of egg production.
Pashubandha 2017 2014
Volume VolumeNo No::06 3 Issue : 08 01
Nishanth, C., Mohan, H.V. and Leena, G. Department of Veterinary Public Health and Epidemiology, Veterinary College Bengaluru, KVAFSU Bidar. e - mail: nishanthvet@gmail.com Trichinellosis is an important meat borne anthropo-zoonotic parasitic disease caused by consumption of raw or under cooked meat of domestic and wild animals infected with larvae belonging to the genus Trichinella. The genus Trichinella has been placed under the Phylum; Nemathelminthes, Class; Nematoda, Order; Enoplida, Superfamily; Trichuroidea and Family; Trichinellidae. Trichinellosis in domestic animals, wild animals and humans has been reported across the globe and it is considered as an emerging or re-emerging food-borne disease of zoonotic diseases. Epidemiology: The epidemiology of the disease is attributed to several factors like socio-economic background, cultural habits, political factors, geographic location, migration of humans and animals. The low prevalence areas of trichinellosis are USA, Canada and European Union and zero prevalence area are Madagascar, Mauritius, Cuba, Sri Lanka and Malta which has been achieved due to strict law enforcement for meat inspection. Economic impact: India has a rich livestock resource with 13.5 million pig population (Agricultural Research Data book, 2007). Each year 84% pigs are slaughtered compared to 6% cattle, 11% buffaloes, 33% sheep and 38% goats. The vast majority of Indian pork utilization is in the form of consumption of fresh pork with very meagre interest on processed pork products. The major portion of pork production in India comes from unorganized sector comprising of free ranging and backyard pig farming. This free ranging and back yard pig production is at particular risk of acquiring the Trichinella infection as they have a more probability of getting exposed to source of infection like infected meat scraps and garbage. Estimate of loss to Indian pig production industry due to trichinellosis cannot be made, since no systematic data on prevalence of trichinellosis at national level are available. Morphology: Morphology of trichinella larvae has a typical comma, curve and tightly coiled shape; length of each larva ranges from 0.92 to 0.97 mm, while width between 20 and 22 Âľm. Host range: Trichinellosis has a wide host range including several species of mammals, reptiles and avian species. The organism has also been recovered from Mircoscopic view of Trichinella domestic cat, civet cat, rodents, domestic pigs and humans in India. Clinical signs: The clinical forms of the disease vary from asymptomatic infection to severe form with life threatening complications like encephalitis and myocarditis. The symptoms may be either enteral or parenteral form. In enteral form increased burden of worms in the intestine may lead to diarrhea, nausea, heartburn and gradual emaciation. Whereas, in parenteral form symptoms includes muscle weakness, joint pain, facial oedema, peri-orbital oedema and death in severe cases. Diagnosis of trichinellosis: Trichinellosis is a well-established zoonosis, its detection in food animals and humans is of paramount importance to take veterinary action and to initiate early treatment in human patients. Detection of trichinellosis in food animals has been made mandatory in European Union.
Pashubandha 2017 2014
Volume VolumeNo No::06 3 Issue : 08 01
Important features of Trichinella species and genotypes Species/ genotype
Geographical distribution
T.spiralis (T-1)
Worldwide
T.nativa (T2)
T.britovi (T3)
T.murrelli (T-5) Trichinella (T-6) T.nelsoni (T-7)
Arctic and subarctic areas of America, Asia and Europe Temperate areas of Europe and Asia, Northern and Western Africa United States and Southern Canada Canada and United States of America EasternSouthern Africa South Africa and Namibia Japan
Trichinella T-8 Trichinella T-9 Trichinella Argentina T-12 Non-encapsulated clade T.pseudospir Worldwide alis (T-4)
T.papuae (T-10) T.zimbabwen sis (T-11)
Papua, New Guinea and Thailand Zimbabwe, Mozambique, Ethiopia and South Africa.
Host range
Freezing Resistance of muscle larvae Yes (in Horse muscle)
Reported human outbreak Yes
Bears and Walruses
Yes (carnivore muscle)
Yes
Sylvatic mammals and seldom domestic pigs
Wild boars, domestic pigs, horses, fox and jackals
Yes (Carnivore and horse muscle)
Yes
Sylvatic carnivores
Bears and horses
No
Yes
Sylvatic carnivore
Carnivores
Yes (Carnivore muscle)
Yes
Sylvatic mammals
Wart hogs and bush pigs
No
Yes
Sylvatic carnivores Sylvatic carnivore Mountain lion
No reports available
No
No
No reports available
No
No
No reports available
Unknown
No
Sylvatic mammals, birds and domestic pigs Wild pigs and salt water crocodile Nile crocodiles, Nile monitor lizards and lion
Domestic and wild pigs
No
Yes
Wild pigs
No
Yes
No reports available
No
No
Domestic sylvatic mammals. Sylvatic carnivores
and
Major source of infection to humans Domestic and sylvatic swine, horse meat
According to the European Union Commission Regulation (EC) No. 2075/2005 it is mandatory to test all the food animals which are susceptible to trichinellosis in slaughterhouses as a part of post-mortem examination before releasing to human consumption (European Community, 2005). The test used for detection of trichinellosis should be reliable, sensitive and should fulfil international standards of quality assurance. Wide array of diagnostic tests with varying specificities and
Pashubandha 2017 2014
Volume VolumeNo No::06 3 Issue : 08 01
sensitivities have been developed for the diagnosis of trichinellosis in humans and animals. The diagnostic tests can be broadly classified as direct and indirect tests. Direct tests: Are those which demonstrate presence of Trichinella larvae in muscle e.g., Trichinoscopy/ compresorium method, artificial digestion assay. Only direct tests, particularly the digestion assays are recommended to use in slaughterhouses for testing of slaughtered food animals to detect trichinellosis. Indirect tests: Are aimed at detecting the specific anti-Trichinella antibodies in the serum, blood or tissue samples. e.g., enzyme linked immune-sorbent assay (ELISA), indirect immune-fluorescence assay (IFA), and immuno-electro transfer blot assay (IETB). The indirect tests are recommended for surveillance and monitoring of Trichinella infection status in farmed pigs, wild animals and indicator species. The indirect tests are not recommended for post-mortem testing of individual carcasses for Trichinella infection. The reason being possibility of false negative results which occur during the initial stage of infection, since development of anti-Trichinella antibodies require 3-4 weeks after the initial infection. Conclusions: Zoonotic trichinellosis remain largely un-recognized in India. The paucity of information on epidemiology with respect to reservoirs, lack of strict meat inspection practices, inadequate cooking of meat and finally lack of awareness in physicians are few among the several factors contributing to the incidence of trichinellosis. Keeping in view, the economic, zoonotic and food safety aspects of trichinellosis such as good farm practices, strict post-mortem inspection of pork and game meat, avoidance of consumption of raw or semi-cooked pork, thorough cooking of meat, effective freezing of pork (-15°C for not less than 3 weeks) and prompt field diagnosis using serological tests helps in proper monitoring and control of the disease.
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monthly e-Bulletin Published and circulated by Veterinary College, Hebbal, Bengaluru. Editor: Dean, Veterinary College, Hebbal, Bengaluru Dr. H.N. Narsimha murthy (Ex-Officio)
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Pashubandha 2017 2014
Volume VolumeNo No : 06 : 3 Issue Issue::08 01