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Mastitis is one of the most prevalent diseases of cattle. Various studies have reported breed-dependent differences in the risk for developing this disease. Among two major breeds, Jersey cows have been identified as having a lower prevalence of mastitis than Holstein cows. It is well established that the nature of the initial innate immune response to infection influences the ability of the host to clear harmful bacterial pathogens. Whether differences in the innate immune response to intramammary infections explain, in part, the differential prevalence of mastitis in Holstein and Jersey cows remains unknown. The objective of the current study was to evaluate several parameters of the innate immune response of Holstein and Jersey cows to intramammary infection with Staphylococcus aureus, a common mastitis-inducing pathogen. To control for non-breed related factors that could influence these parameters, all cows were of the same parity, in similar stages of milk production, housed and managed under identical conditions, and experimentally infected and sampled in parallel. The following parameters of the innate immune response were evaluated: acute phase protein synthesis of serum amyloid A and lipopolysaccharide-binding protein; total and differential circulating white blood cell counts; milk somatic cell counts; mammary vascular permeability; milk N-acetyl-beta-d-glucosaminidase (NAGase) activity; and production of the cytokines, interferon (IFN)-gamma, interleukin (IL)-12, tumour growth factor(TGF)-alpha, and TGF-beta1. The temporal response of all of these parameters following infection was similar between Holstein and Jersey cows. Further, with the exception of changes in circulating neutrophils and NAGase activity, the overall magnitude of these parameters were also comparable. Together, these data demonstrate that the innate immune response of Holstein and Jersey cows to Staph. aureus intramammary infection remains highly conserved despite previously reported differences in mastitis prevalence, as well as genotypic and phenotypic traits, that exist between the two breeds.

In October 2020, three captive male white-tailed deer, Odocoileus virginianus [Zimmermann] (artiodactyla: Cervidae), were found dead in central Pennsylvania and a fourth was euthanized due to extreme lethargy. The deer presented with high burdens of Dermacentor albipictus (Packard) (Ixoda: Ixodidae) (winter tick). There were no other clinical symptoms and deer were in otherwise good physical condition with no observed alopecia. Winter tick epizootics have been associated with mortalities of moose, Alces alces [Linnaeus] (artiodactyla: cervidae), and more recently elk, Cervus canadensis [Erxleben] (artiodactyla: cervidae), in Pennsylvania, but have not been reported in white-tailed deer. Mild winters are favorable to winter ticks and deer producers and managers should be aware of possible infestations as a result.

We report four full-genome sequences of bovine coronavirus (BCoV) isolates from dairy calves in Pennsylvania obtained in 2016 and 2017. BCoV is a pathogen of great importance to cattle health, and this is the first report of full-genome sequences of BCoV from PA cattle.

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