Joseph S. Hogan

The National Mastitis Council: A Global Organization for Mastitis Control and Milk Quality, 50 Years and Beyond

The National Mastitis Council was founded in 1961 based on the desire of a forward-thinking group of individuals to bring together “all forces of organized agriculture in the United States to combat, through every practical device, the mastitis threat to the Nation’s health and food safety”. What started as a small organization focused on mastitis of dairy cattle in the United States has grown into a global organization for mastitis and milk quality. Over the last 50-plus years the concerted efforts of the membership have led to the synthesis and dissemination of a considerable body of knowledge regarding udder health, milk quality, and food safety which has improved dairy cattle health and well-being and farm productivity.

Meta-analysis of the effects of sometribove zinc suspension on the production and health of lactating dairy cows

OBJECTIVEnTo provide an updated evaluation of the efficacy and safety of sometribove zinc suspension (rbST-Zn), a form of recombinant bovine somatotropin, in lactating dairy cows.nnnDESIGNnMeta-analysis.nnnSAMPLEn26 studies published in peer-reviewed journals or reviewed by a regulatory agency.nnnPROCEDURESnTo be included, a study had to involve the use of the rbST-Zn formulation available to US producers in accordance with the label instructions for treatment initiation (57 to 70 days postpartum), dose (500 mg, q 14 d), and route (SC).nnnRESULTSnFor cows treated with rbST-Zn, mean milk, 3.5% fat-corrected milk, fat, and protein yields were increased by 4.00, 4.04, 0.144, and 0.137 kg/d (8.8, 8.89, 0.32, and 0.30 lb/d), respectively; however, the concentration of milk components did not change. Pregnancy proportion for the first 2 breeding cycles was increased by 5.4%, and pregnancy proportion for the duration of the trial was reduced by 5.5% for rbST-Zn-treated cows, compared with proportions for untreated cows. Mean body condition score (1 to 5 scale) was reduced by 0.06 points during the period of rbST-Zn use for treated cows. Administration of rbST-Zn had no effect on milk somatic cell count, the number of days to pregnancy, or inseminations per pregnancy; rates of fetal loss, twins, cystic ovaries, clinical lameness, lameness lesions, or traumatic lesions of the integumentary system; and odds of clinical mastitis or culling.nnnCONCLUSIONS AND CLINICAL RELEVANCEnResults indicated that rbST-Zn administration to dairy cows effectively increases milk production with no adverse effects on cow health and well-being.

The ability of common mastitis-causing pathogens to survive an ensiling period

A forage-based study was conducted to examine the ability of enterococci, streptococci, and gram-negative bacteria to survive a 3-wk ensiling process. Harvested grass and corn forages were each divided into 3 treatment groups consisting of 2 commercially available silage inoculants and 1 negative control group. Within 24h of harvest, a uniform amount of forage was added to each of 18 vacuum-sealable freezer bags. Inoculants 1 and 2 were applied to each of 6 bags and the remaining 6 bags were not inoculated (negative control). All bags were sealed using an industry-grade vacuum sealer to create a pillow pack. At wk 1, 2, and 3 of the ensiling process, 6 bags were opened, 2 from each of the 3 groups. Dry matter (DM), pH, and bacterial enumeration were determined on the forage before ensiling, as well as at wk 1, 2, and 3 of ensiling. The pH of grass and corn samples decreased to 5.2 and 4.1, respectively, by the end of the ensiling period. Inoculant 2 (7.3 log(10) cfu/g of DM) resulted in a greater enterococcal count in grass samples than did inoculant 1 (4.2 log(10) cfu/g of DM) at 3 wk of ensiling and both were greater than the negative control (1.2 log(10) cfu/g of DM). Counts of streptococci in grass samples at wk 3 were greater in inoculated samples (inoculant 1, 7.6 log(10) cfu/g of DM; inoculant 2, 7.0 log(10) cfu/g of DM) compared with the negative control (4.3 log(10) cfu/g of DM). Treatment differences were observed following 1 wk of ensiling in corn samples. Enterococcal counts on corn samples following the 3-wk ensiling were not significantly different between inoculant 1 (4.3 log(10) cfu/g of DM) and inoculant 2 (4.4 log(10) cfu/g of DM). However, counts in both inoculated groups were greater than in the negative control group (4.0 log(10) cfu/g of DM). No significant treatment differences were observed for streptococci counts at wk 3. Counts for gram-negative bacteria were not detectable by wk 3 of ensiling in either grass or corn samples. The addition of a silage inoculant led to greater counts of enterococci and streptococci in grass silage compared with the negative control at the end of a 3-wk ensiling period. The application of a silage inoculant led to increased enterococci counts, but not streptococci counts, in corn samples following the ensiling period. These data indicate that enterococci and streptococci are able to survive the pH decrease observed during ensiling.