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In the United States (US), a national control program from bovine tuberculosis (bTB) has been successful at greatly reducing the incidence of Mycobacterium bovis infection in domestic cattle and mitigating exposure to humans. However, experience in many countries, including the US, has demonstrated that eradication of animal tuberculosis (TB) from wildlife can complicate disease control programs. Wild pigs may serve as an important maintenance species for TB, contributing to outbreaks in cattle and hampering disease control programs. In the US, on the Hawaiian island of Molokai, wild pigs facilitated TB transmission, but risk factors contributing to infection of TB were not characterized. To fill this gap, we retrospectively analyzed data from an outbreak of M. bovis in wild pigs and domestic cattle in California during 1961-1967. Using generalized linear models we investigated demographic risk factors (age and sex) for TB infection in wild pigs as well as the association among wild pig and domestic cattle prevalence. Our models demonstrated a predictive accuracy of 87.8 % and suggest adult female wild pigs have significantly lower odds of being TB positive (odds ratio (OR) = 0.41, p value = 0.022). Furthermore, our models identified a possible positive association between male wild pigs and TB status (OR = 2.37, p value = 0.055). We also found evidence of differences in geographic risks. Our findings contribute to the existing literature describing risk factors of M. bovis infection in wild pigs and can be used to support targeted surveillance activities in wild pigs., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The study objective was to compare the efficacy of 3 commercial dry cow mastitis formulations regarding quarter-level prevalence of intramammary infections (IMI) postcalving, cure of preexisting infections over the dry period, prevention of new infections during the dry period, and risk for a clinical mastitis case between calving and 100d in milk (DIM). A total of 1,091 cows (4,364 quarters) from 6 commercial dairy herds in 4 different states (California, Iowa, Minnesota, and Wisconsin) were enrolled and randomized to 1 of the 3 treatments at dry-off: Quartermaster (QT; 1,000,000 IU of procaine penicillin G and 1 g of dihydrostreptomycin; Pfizer Animal Health, New York, NY), Spectramast DC (SP; 500 mg of ceftiofur hydrochloride; Pfizer Animal Health), or ToMorrow Dry Cow (TM; 300mg of cephapirin benzathine; Boehringer Ingelheim Vetmedica Inc., St. Joseph, MO). Quarter milk samples were collected for routine bacteriological culture before dry cow therapy treatment at dry-off, 0 to 6 DIM, and 7 to 13 DIM and an on-farm record-keeping system was used to retrieve data on clinical mastitis cases. Noninferiority analysis was used to evaluate the effect of treatment on the primary outcome, risk for a bacteriological cure during the dry period. Multivariable logistic regression techniques were used to describe the effect of treatment on risk for presence of IMI postcalving and risk of a new IMI during the dry period. Cox proportional hazards regression was used to describe the effect of treatment on the risk and time for quarters to experience an episode of clinical mastitis between calving and 100 DIM. The overall crude quarter-level prevalence of infection at dry-off was 19.2%. The most common pathogen isolated from milk samples at dry-off was coagulase-negative Staphylococcus, followed by Aerococcus spp. and other Streptococcus spp. Noninferiority analysis showed no effect of treatment on risk for a cure between dry-off and calving [least squares means (LSM): QT=93.3%, SP=92.6%, and TM=94.0%] and secondary analysis showed no effect of treatment on risk for presence of an IMI at 0 to 6 DIM (LSM: QT=16.5%, SP=14.1%, and TM=16.0%), risk for development of a new IMI between dry-off and 0 to 6 DIM (LSM: QT=14.8%, SP=12.3%, and TM=14.2%), or risk of experiencing a clinical mastitis event between calving and 100 DIM (LSM: QT=5.3%, SP=3.8%, and TM=4.1%). In conclusion, no difference was observed in efficacy among the 3 products evaluated when assessing the aforementioned quarter-level outcomes., (Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)