QMPS: AABP mastitis research updates

Editor's note: The following article appeared in the January 2016 issue of Dairy Herd Management.

Several veterinarians from Cornell's Quality Milk Production Services (QMPS) attended the American Association of Bovine Practitioners (AABP) Conference, presenting research and learning from other animal health leaders. Following are some milk quality highlights from the meeting, summarized by Jessica C. Scillieri, DVM, and Francis Welcome, DVM.

QMPS offered a one-day, milk quality short course to more than 40 veterinarians.

• DR. DARYL NYDAM presented research on making pathogen-based treatment decisions using daily sample submissions, with results reported back to the farm within 24 hours.

• DR. PAUL VIRKLER described how scoring short-term teat skin changes (teat color, swelling and edema) can help identify problems that may influence mastitis risk. This tool can help assess teat dip effectiveness by tracking teat skin condition, changes in vacuum, automatic take-off performance and milking procedures.

• DR. RICK WATTERS addressed methods for evaluating and optimizing parlor throughput.

• DR. FRANK WELCOME highlighted the importance of record keeping for continuous improvement through somatic cell count (SCC) management.

• DR. JESSICA SCILLIERI SMITH introduced a potential emerging pathogen, Lactococcus species. Laboratories previously reported this pathogen group as Streptococcus species. Recent investigations have shown Lactococcus spp. to compose a large percentage of pathogens in this generic category of streptococcus species on some farms, but was not as prevalent as Streptococcus dysgalactiae or Streptococcus uberis.

Mastitis research summaries were presented.

• DR. AMY VASQUEZ, Cornell University, presented research comparing blanket treatment (control group) of clinical mastitis to a pathogen-based (experimental) group treatment protocol for cows with non-severe clinical mastitis. The pathogen-based approach utilized results from a reference lab within 24 hours of submission, allowing the farm to delay therapy until a culture result was available. The treatment protocol focused treatment on cows with Streptococcus, Staphylococcus and Enterococcus infections. Cows with other culture results - such as E. coli, klebsiella spp., yeast or no-growth - were not treated. Results showed no difference in the number of days until a clinical cure, risk of culling, SCC or milk production on the following test day between the two groups. The research did show a significant increase in the number of days out of the tank for milk from cows in the control group. Dr. Michael Capel, a dairy practitioner from Perry, N.Y., presented the economic effect of this study, concluding pathogen-based therapy provided a gain of $30,000 per 1,000 cows in reduced costs and increased income.

• JULIA SIMONS, University of Wisconsin, used a retrospective, two-year study on a 3,600-cow dairy to evaluate the effect of removing a quarter (killing a quarter) on milk production. Cows with only three quarters in production made about 1,500 lbs. less milk than those with four functional quarters (comparing 305-day ME data). However, cows with three functional teats were 31% less likely to leave the herd. Days in milk at the time of culling was greater for those with three teats. This study shows removing a quarter from production will affect milk production, but only minimally, and may be a management strategy to help keep animals in the herd longer.

The association between bedding types and milk quality in Wisconsin was investigated by DR. PAMELA RUEGG. Milk quality data was collected for a two-year period on farms shipping 25,000 lbs. of milk daily. Bedding types were lumped into three categories: inorganic material (sand), manure solids (mostly from digesters) and organic material (wood products). Farms using manure solids were found to have more milk withheld from sale, and a higher percentage of cows with fewer than four quarters in production. Farms using inorganic materials were found to have a lower bulk tank SCC than those with organic material or manure solids.

• DR. PAT GORDEN, Iowa State University, discussed the pharmacokinetics (tracing a drug from the moment it is administered to the point at which it is completely eliminated from the body) of ceftiofur hydrochloride given via the intramuscular route for five days in cows with severe mastitis. This research shows sick cows process some drugs differently than healthy cows. Change in pharmaco-kinetics may decrease the efficacy of this antibiotic and increase the risk of an antibiotic residue.

Quality Milk Production Services (QMPS) promotes the production of high quality milk through diagnosis and control of mastitis and the avoidance of antibiotic residues in milk. Field and laboratory diagnostic evaluations and recommendations are conducted through four regional laboratories in New York (Ithaca, Cobleskill, Canton and Geneseo). Visit https://ahdc.vet.cornell.edu/Sects/qmps/