Kentucky Dairy Notes Weaning Dairy Calves from an Automatic Feeder By: Katie Kelly and Donna Amaral-Phillips, Ph.D.
Over the years, the practice of feeding calves through an automatic feeding system has been explored. Even though the conventional way of feeding milk or milk replacer to calves individually 2 or 3 times daily has been proven to result in healthy and profitable calves, some farmers are considering ways to reduce time spent feeding calves. Most automatic calf feeders are programmed to use accelerated calf feeding programs where more total volume of milk is fed per day but in smaller more frequent meals, similar to how a calf nurses its dam. This automatic system identifies a calf through an ear tag or a neck collar and dispenses an amount of milk based on how the system has been programmed, such as based on age, body weight, etc. When managed properly, this feeding system provides for excellent growth of the calf. Additionally, when these systems are used correctly, they can reduce the stress on the calf at the time of weaning. Some key points to remember when weaning calves from an automatic calf feeding system include:
Program automatic calf feeder carefully to meet your goals when weaning calves. At the time of weaning, calves usually are consuming between 8 to 16 quarts/day of milk or reconstituted milk replacer, depending on how the feeder was programmed and the goals of the operation. These calves usually visit the feeder 4 to 8 times per day and consume around 2 quarts per visit. The computer will then recognize that the calf is at a management-determined age, usually 50 days of age. Now, the computer will start reducing the amount of milk the calf receives during each visit and decrease the number of visits where milk is available to the calf each day. This step-down process is usually done over a week to 10 days. After this time period, the computer will stop providing milk to the calf.
February 2017 Take it slowly. With accelerated calf feeding programs, more milk is fed during the suckling phase than conventional calf rearing methods. Feeding these higher amounts of milk likely means that calves are not eating as much starter as calves that are fed on a conventional system where less milk is fed. To stimulate increased intake of starter, weaning should occur over a 1- to 2-week period whereby the amount of milk fed is slowly decreased. When calves are weaned suddenly over a shorter period, the intake of starter is not sufficient to provide for the energy needs of the calf. Consequently, the calf may not gain weight or may actually lose weight during the weaning phase. By reducing the amount of milk calves receive at each visit, this will promote the calf to consume more starter and increase energy intake from the starter while decreasing energy supplied through the milk. Additionally, this weaning technique will decrease the number of unrewarded visits than if the amount of milk is removed quickly, decreasing the stress to the weaning calf.
Always have starter and clean water available. Water always should be available and starter should be available after three days of age or when the calf is introduced to group housing. As the calf drops in milk consumption, it will begin to consume more starter to keep from becoming hungry. If adequate amount of starter is not available, behavior changes to show signs of hunger, such as bawling, and more unrewarded visits to the feeder will occur. Water intake is also directly related to feed intake, so the more feed the calf consumes, the more water it will
Weaning Dairy Calves ‌ continued consume. Water provides moisture to rumen bacteria and along with calf starter intake creates a perfect environment for rumen fermentation and the subsequent development of rumen papillae. Additionally, clean water helps prevent diarrhea, even before the weaning process. Don’t change too many things at once. It may be tempting to remove the recently weaned calf from the pen right away to provide space for a new calf or to prevent the weaned calf from blocking the feeder from other calves. The weaning period is a big stressor for calves. During periods of stress, animals will reduce feed intake which can decrease average daily gain. Reducing the number of changes that are occurring at a given time should reduce the stress experienced by calves. Once the calf has been successfully weaned, the calf should remain with the group for one to two weeks after weaning. This allows the calf to adjust to only consuming dry feed and should decrease stress before moving to a new pen with differing social interactions. An automatic feeding system can be a great addition to a calf raising operation. It can provide higher growth rates and a better start associated with accelerated feeding of milk. By being able to decrease the amount of milk and the number of feedings, this system can allow the calf to be weaned slowly and automatically. Properly operated automatic calf feeders can decrease stress, improve starter intake, and decrease the amount of weight loss during the weaning period.
Reproductive Management: What Should we Focus on Next?
Calf Facility at University of Kentucky Coldstream Dairy
result in identical twins). Instead, most twins result from double ovulation. This is when two follicles are selected to ovulate instead of just one. This double ovulation is triggered when the cow has low progesterone levels during the selection phase, or when follicles By: Karmella Dolecheck, Katie Kelly, and Jeffrey Bewley become dominant over others and are chosen to ovulate. Low We have learned a lot about reproductive management over the progesterone can be due to many things. Most commonly, high milk last 20 years. Although it seems like they have been around forever, the producing cows experience greater feed intakes, leading to higher liver most commonly used synchronization protocols (Ovsynch, Presynch, blood flow and resulting in faster progesterone break-down. and Resynch) were not developed until the late 1990s. We started If twinning is a problem in your herd, practices can be implemented using CIDRs in the early 2000s. Sexed semen and the first activity to reduce and manage it. To reduce the occurrence of twins, monitoring systems were commercialized only 12 years ago in 2005. progesterone levels need to increase during follicle selection. The best Genomic data was added to sire summaries in 2007. way to do this is by breeding cows using a Double Ovsynch protocol All of these advances have resulted in overall improved (see example below). Additionally, using a CIDR in resynched cows reproductive performance, but we still have room to improve. Each year that do not have a CL can decrease the chance of twins. If twins are the Dairy Cattle Reproductive Council comes together to discuss new already present, the location of the pregnancies determines the best reproductive management ideas. A few items that were highlighted at way to handle them. If the twins are in different horns, or bilateral twins, the 2016 annual meeting in Columbus, Ohio included managing both calves have a good chance of survival with low complication rates. twinning rates and striving for the economically optimal pregnancy rate. Bilateral twins only result in around a 7% pregnancy loss and for the most part the pregnancy should be continued. If the pregnancies are in Managing Twins the same horn (unilateral), the chance for pregnancy loss greatly Twinning rates in the dairy industry have increased in recent years. increases. In this case, the herd manager should consider terminating According to Dr. Paul Fricke from the University of Wisconsin, very few the pregnancies or have a veterinarian attempt to selectively eliminate twins result from a single ovulated egg that splits in half (which would one calf.
Reproductive Management: What Should we Focus on Next? ‌ Continued Economically Optimal Pregnancy Rate When we think about pregnancy rate, we tend to think of bigger as better. But is there a point where that is not true – can pregnancy rate be too high? Dr. Albert DeVries from the University of Florida has been considering this question. According to his research, we have not yet identified a point where improving pregnancy rate does not improve overall herd performance. However, improved herd performance is only half of what we need to consider to find the economically optimal pregnancy rate. The other half is the cost associated with increasing the pregnancy rate. In other words, if we improve herd performance via increased pregnancy rates but spend more than that improvement is worth to do so, we are not actually improving overall herd profitability. This is important to keep in mind, especially when considering management changes focused on increasing pregnancy rate in a herd that is already accomplishing a high pregnancy rate. The value of increasing pregnancy rate shows diminishing returns, meaning that when pregnancy rate is already high there is less value in increasing it (i.e. increasing pregnancy rate from 18 to 20% is more valuable to overall herd performance than increasing pregnancy rate from 28 to 30%). Therefore, improving pregnancy rate in high pregnancy rate herds requires cheaper management changes. In addition to the cost of management changes, other factors impacting increased pregnancy rate need to be considered. For example, with increasing pregnancy rates less cows will be culled for reproductive failure and more heifers will freshen or be available to sell. Ultimately, the economically optimal pregnancy rate depends on many herd-specific factors, but especially the costs associated with making the management changes that result in an increased pregnancy rate.
Example Double Ovsynch Protocol
Upcoming 4-H Events State 4-H Dairy Jeopardy This contest is an annual event that allows 4-H members ages 9 to 18 to show off their knowledge of the dairy industry by answering questions on a wide variety of dairy topics. Topics include: nutrition, reproduction, genetics, showing, judging, dairy products, milking, and lots more. Date: March 14, 2017 Location: Barren County Extension Office Registration Deadline: February 27, 2017 (Please return registration forms to Larissa Tucker) State 4-H Dairy Cow Camp Annual dairy judging workshop for 4-H members to practice dairy judging and oral reasons. Date: April 22, 2017 Location: Barren County Fairgrounds Registration: Will be due sometime early April to Barren County Extension Office
UNIVERSITY OF KENTUCKY, KENTUCKY STATE UNIVERSITY, U.S. DEPARTMENT OF AGRICULTURE, AND KENTUCKY COUNTIES, COOPERATING
Determining Cause and Incidence Rate of Clinical Mastitis in Dairy Cattle By: Abbey Chandler & Dr. Donna Amaral-Phillips Mastitis is one of the more expensive infections on a dairy operation. The average case of mastitis cost farmers $325 this includes vet costs, treatment, labor, discarded milk, decreased milk production, culling, extended days open, and death (Liang and Others, 2016). The difference between clinical and subclinical mastitis is that with clinical mastitis the cow shows signs of an infection. The following discussion will focus on determining the cause and incidence of clinical mastitis. Since subclinical cases can’t be detected easily and are still costing you money without you even knowing it the key to controlling both types of mastitis in your herd is prevention. What causes clinical mastitis? The most effective way to determine what organism causes clinical mastitis in a herd is to culture milk samples. To culture a milk sample means to place the milk sample in a sterile dish with a growth medium in a lab and provide an environment for whatever bacteria is present in the milk to grow. Then, once the bacteria have grown for a certain amount of time, a lab technician or researcher can evaluate the sample and determine the causative pathogen. Research using bacteria cultures shows that the majority of clinical mastitis cases are caused by five main bacteria. They are: E. coli (and other coliforms), Streptococcus spp., Bacillus spp., and Staph. aureus. Although considered a minor pathogen, coagulase-negative staphylococci are also frequently isolated from clinical samples. How do you determine which bacteria is causing clinical mastitis in your herd? Bacterial cultures of milk samples from infected cows in your herd are needed to determine which bacteria is/are causing your problem. Milk samples need to be collected aseptically following strict procedures BEFORE THE COW IS TREATED. To collect samples for culturing: 1. Obtain sterile vials from either a diagnostic lab or milk cooperative such as DFA. 2. Wear gloves when collecting the samples. 3. Begin by preparing the cow or cows to be sampled just as you would prepare them for milking. Fore strip, pre-dip, then wipe clean with a dry towel or cloth. Next take a cotton ball moistened with rubbing alcohol, but not dripping wet, and for 15 to 20 seconds scrub the teat end. Continue doing this with new cotton balls until the cotton ball is still white after cleaning the teat end.
4. Do not open the collection vial until you are ready to take the sample. Hold the vial at a 45-degree angle and do not touch the inside of the lid. Also do not lay the lid on the ground, hold it facing down to minimize the risk of contamination. 5. Do not let the teat touch the collection vial, but aim for direct streams of milk into the vial. Do this as rapidly as you can, but be careful to avoid contamination. Do not fill the vial completely full as the sample will need to be frozen until it can be taken to the lab and if the vial is too full when it is frozen it will bust and your sample will be lost. Avoiding contamination is a huge concern because contamination causes a greater chance of skewed results including other bacteria than those causing the mastitis as well as overgrown cultures that cannot be analyzed correctly. Knowing the specific pathogen
causing the mastitis in your herd will allow you to treat infected cows more effectively. An important thing to note however, is that 40 to 50% of bacteria cultures come back as no growth. Reasons for this can be that the cow may have already been treated with antibiotics, that the cow’s body has already dealt with the infection on her own or bacterial numbers are too low to detect. For the other 50-60% of cultures, with the exception of overgrowths, the results can lead you to the best course of treatment and management practices for the specific pathogen causing problems in your herd. How much is too much clinical mastitis? To answer this question, you must determine the incidence rate for clinical mastitis in your herd. Simply put incidence rate for clinical mastitis is the percentage of cows in your herd with a case of clinical mastitis during their current lactation. So to determine your incidence rate you would take the number of cows with a case of clinical mastitis this lactation and divide it by your total number of cows and multiply that number by 100 to get a percentage. According to a research study done at the University of Wisconsin School of Veterinary Medicine, conducted by Nigel Cook and Rebecca Mentink, the average incidence rate of mastitis on a conventional dairy operation is 32%; this means 32 out of 100 cows on average have a case of clinical mastitis in this lactation. In a perfect world even one case of clinical mastitis is too much, but achieving that low of an incidence rate is virtually impossible for many reasons. With that being said it is not uncommon in some of the top herds for the incidence rate of clinical mastitis to be below 10 to 15%. So practically speaking, how much is too much? This answer can be different for every herd depending on the standards you are trying to maintain. In general, the higher the incidence rate the more money lost. Therefore, the lower the incidence rate the better. Prevention is key. Preventing mastitis is by far the best, most cost effective option there is. There are several things you can do to prevent mastitis in your herd. The simplest thing is to make sure all employees are trained and that proper milking and sanitation procedures are followed. Determine problem areas on your farm where the cows most often are exposed to the pathogen causing your mastitis and correct the problem or keep the cows out of that area as much as possible. To reduce the spread of mastitis from cow to cow in your herd use an effective pre and post dip as well as clean, well-maintained milking equipment. Using dry cow treatment at dry off as well as an internal teat sealant, such as Orbaseal, and a coliform vaccine can also help prevent mastitis during the dry period and in the next lactation.
Management Practices of Close-up Dairy Cows By: Sarah Mac and D.M. Amaral-Phillips The dry period is essential to the success of that cow in her next lactation. Properly managing dry dairy cows is just as important as programs for lactating cows, and yet dry cows often seem to be neglected and forgotten. A critical time in the dry period is the last three weeks before calving, also known as the “close-up” period. During this time, the cow is preparing to start the next lactation. Without adequate management, cows can calve in and fade quickly and lose potential income for their owners. Key management practices: moving cows to the close up pen three weeks before their due date, changing the feed ration, minimizing stress, and using heat abatement are recommended for close-up dry cow and it is important to understand why these practices are important. Why Three Weeks? Dry cows should be moved to the close-up pen three weeks before due date, but where does this recommendation come from? For a lactating cow to be successful, she needs to be able to mobilize calcium from her bones and absorb calcium in her intestines. During the dry period she has not needed to mobilize calcium in great quantities in comparison to the lactation period so her body needs help to start the process to mobilize calcium. This process can take 10 to 15 days. Without adequate time to prepare for lactation, milk fever, both clinical and subclinical (which we cannot see), can be a major issue. Not only are you giving time to set the stage to mobilize calcium, your cows need time for their rumen to adapt to the forages and higher energy diets which are essential to absorb nutrients and prevent problems after calving. Why Change the Feed Ration? Feed rations should change throughout the dry period because the first 5 weeks, the cows are fed for maintenance and the last three weeks cows are fed for preparation of entering the lactating herd. Forages low in energy should be fed during the dry period. In the close-up period, forages should make up about 70 to 80% of the ration. High forage content is important to provide rumen fill as well as adequate but not excessive fiber while still maintaining body stores. Too much weight at the beginning of the lactation can result in fatty liver disease. This
diet should still be low in energy, but grain should be introduced during the close-up period. Depending on the quality and type of forages available, 3 to 8 pounds of grain a day may be recommended. Feed additives are used to help cows cope with the demands for milk production after calving. Feeding protected choline helps prevent fat accumulation in the liver. Anionic salts help the cow’s body get ready to mobilize calcium. Vitamin E is essential for prevention and decrease the severity of mastitis, as it helps improve the immune system. Why Minimize Stress? The close-up period is already a stressful time for the dam, and decreasing external stresses can help with calving ease, immunity, feed intake, and overall well-being of the cow. Some ways to decrease stress are providing enough feedbunk space (36 inches per cow), limit the number of pen moves (ideally no pen moves), minimizing heat stress, and giving cows enough resting space (at least a 1:1 ratio of beds to cows housed in freestalls or 100 to 125 square feet for bedded pack). Why Use Heat Abatement? Heat abatement through the use of shade, fans and sprinklers is essential for all groups of cows. However, major repercussions can happen if it is not implemented for dry cows. If a dry cow experiences heat stress it can cause her to calve early, decrease her immune system function, decrease milk production in the next lactation, and decrease conception rate. Heat stress also affects the fetus and the calf after she is born. Calves born to heat stressed dams are lower in body weight and have lower milk production when she calves in as a heifer. So, heat abatement isn’t just important for this dam, but the next generation as well. Take Home Message: Close-up dry cow management is essential to an easy transition into the milking herd. Some management practices that are recommended are moving far off dry cows to the close-up pen three weeks before their due date, changing the feed ration to prepare the rumen for the lactating cow diet, minimizing stress and using heat abatement practices. A successful close-up period is linked to a successful lactation.
Join us for the 10th annual Kentucky Dairy Partners Meeting February 21 & 22, 2017
Sloan Convention Center, 1021 Wilkinson Trace, Bowling Green, Kentucky Day One 8:30 AM KDDC Young Dairy Producers Conference 9:30—11:00 Trade Show Set Up 2:00 PM ADA of Kentucky Board Meeting 6:00 PM Dairy Awards Banquet Day Two 9:00 AM Welcome and Annual Meeting Begins Trade Show will be open both days and Door Prizes will be given There will also be a Silent Auction Registration Fee: $25 per dairy farm for both days
$30 for industry members each day Holiday Inn Hotel room rate is $99 and room block ends February 1, 2017 Call 270-745-0088 under Ky Dairy Partners