Feed additive against subclinical mastitis

STOCK SUB-CLINICAL MASTI

Incorporation of OxC-beta in feed may aid in control of mastitis.

Words by: Scott McDougall Avivagen, a Canadian animal health company, approached him about running

Abeta-carotene feed additive has a trial to assess their non-antibiotic OxCbeen investigated as a way of beta product against subclinical mastitis treating subclinical mastitis. and he was intrigued to investigate further,

Control of mastitis in McDougall said. dairy herds is well understood, with “OxC-beta is formed by complete adherence to strict protocols and controlled oxidation of betagenerally leading to low carotene and has been shown levels of infection in most to support immune function herds. However, even in by increasing the ability of well-managed herds there the cows natural defences to remain some animals that detect and destroy bacteria carry subclinical infections. while maintaining moderate Antibiotic treatment of these levels of inflammation.” subclinical infections is generally From four spring-calving dairy not advisable as the cost of milk Scott McDougall. herds Cognosco selected high discarded after treatment likely somatic cell-count (>200,000 outweighs the benefit. A non-antibiotic cells/mL) cows with infection confirmed approach, however, could be a useful by microbiology and an elevated SCC in strategy to help the infection. one or more quarters. Cows were then

Veterinarian Scott McDougall from randomly assigned within each herd to Cognosco, the research group at Waikato’s be fed meal (0.5 kg/cow/day) with OxCAnexa Veterinary Services, investigated beta or without OxC-beta for six weeks. use of a special form of beta-carotene (the The two treatment groups were balanced precursor to vitamin A) in treating existing within each herd by breed, age, and days subclinical mastitis cases. in milk at the commencement of feeding.

Quarter-level somatic cell count data, herd test data, and clinical mastitis treatment records were collected and analysed. A range of different bacterial species was isolated prior to treatment with the most common bacteria being minor pathogens. However, a number of quarters were infected with major pathogens including S. aureus, S. dysglactiae, and S. uberis.

About twice as many quarters from cows fed OxC-beta cured than from the control group (13.9% vs 6.9%). Fewer of the quarters in cows fed OxC-beta had clinical mastitis in the six weeks after the start of feeding compared with quarters from control fed cows (0.8 % vs 4.4%). But there was no effect of OxC-beta feeding on the quarter-level somatic cell count after treatment, the herd test somatic cell count, milk production L/cow/day, or milk fat or protein percentage.

Results suggest the immune supporting actions of OxC-beta may aid in control of mastitis by reducing the number of infected animals and reducing the risk of subsequent clinical mastitis.