Wildfires are increasing in frequency and severity across the Western United States. However, there is limited information available on the impacts these fires are having on the livelihood of livestock producers and their animals. This work presents the results of a survey evaluating the direct and indirect impacts of the 2020 wildfire season on beef cattle, dairy cattle, sheep, and goat, producers in California, Oregon, and Nevada. Seventy completed surveys were collected between May and July 2021. While dairy producers reported no direct impacts from the fires, beef, sheep, and goat producers were impacted by evacuations and pasture lost to fires. Only beef producers reported losses due to burns and burn-associated deaths or euthanasia. Dairy, beef, sheep, and goat producers observed reduced conception, poor weight gain, and drops in milk production. All but dairy producers also observed pneumonia. Lower birthweights, increased abortion rates, and unexplained deaths were reported in beef cattle, sheep, and goats. This work documents the wide-ranging impacts of wildfires on livestock producers and highlights the need for additional work defining the health impacts of fire and smoke exposure in livestock, as well as the policy changes needed to support producers experiencing direct and indirect losses.

Corynebacterium pseudotuberculosis is a facultative intracellular pathogen responsible for chronic infections in livestock, primarily small ruminants and horses, with occasional zoonotic transmission. To investigate the genomic diversity, evolutionary stability, and host adaptation of this species, we analyzed 788 high-quality genomes representing isolates from diverse hosts, geographic regions, and time periods. Comparative population genomics revealed remarkably conserved genome architecture, supporting a closed pangenome with minimal accessory gene variation. Virulence and antimicrobial resistance (AMR) screening across multiple databases confirmed the universal presence of phospholipase D (pld) and the absence of major horizontally acquired AMR determinants, except for APH(3’)-IIa, TEM-116, and APH(3’)-IIIa in a few goat isolates from Brazil. Distinct metabolic features between biovars were conserved, notably nitrate reduction and molybdenum cofactor biosynthesis in biovar equi. However, gene presence/absence alone did not explain host specificity. Instead, machine learning applied to 8,028 core-genome SNPs identified allelic variants associated with host origin, particularly in genes linked to amino-acid biosynthesis and peptide transport (Opp system). These findings demonstrate that host adaptation in this species is driven by fine-scale SNP variation within core metabolic pathways, rather than acquisition of classical virulence or resistance genes, highlighting the species’ exceptional genomic stability and narrow evolutionary flexibility.

(1) Background: Information is lacking on small ruminant lentivirus (SRLV) status, prevalence, risk factors, and control measures for mastitis in California ewes. The goal of this survey was to outline characteristics of the sheep industry in California related to udder health and mastitis management. (2) Methods: An online survey consisting of 48 questions was completed by respondents between April 2022 and February 2023. Descriptive analysis and chi-squared tests were conducted to evaluate associations between variables. A multiple correspondence analysis (MCA) of general management practices, udder health management, and flock demographics was performed to assess clustering. A subset of respondents (20) participated in SRLV serology testing. (3) Results: Seventy-one completed surveys were submitted. The MCA showed two clusters. Larger flock sizes, the use of breeding ewes for meat or wool production or contract grazing, and extensive management practices were more closely related to >5% udder abnormalities per lactation and ≥5% orphan lambs. The flock-level seroprevalence of SRLV was 75% (15/20), and ewe-level seroprevalence was 14.1% (183/1106). (4) Conclusions: The results of this study highlight areas that need further research, such as exploring differences in mastitis and SRLV incidences among management systems, the efficacy of mastitis treatments, and education on critical timepoints for mastitis diagnosis and control.

The number of small-scale and backyard operations has increased in the United States during the past decade, but there is currently a lack of outreach efforts and readily-available educational materials targeting these farming systems. We developed a webinar series on biosecurity to provide training for small-scale and backyard producers, and training tools that can be used by local veterinarians and extension educators to disseminate knowledge and consistent recommendations more effectively. Fewer people attended the webinars than registered, suggesting a gap between interest in biosecurity and commitment to the topic. Participants in the webinar series reported a high level of satisfaction and a significant increase in knowledge.

The lack of individual performance records derived from an extensively driven production system coupled with impracticality to utilize reproductive technologies makes commercial genetic improvement challenging in small ruminants. We collaborated with five producers throughout California to assess how Electronic ID (EID) and a genotyping panel can augment the productivity of a flock. We sought to study how the data collected from these technologies can hasten genetic improvement towards desirable operational objectives. Familiarity and use of EID tags on ranches at the start of the research varied; thus, allowing for a qualitative reflection on the perceptions of the participants of the usefulness of this technology. We partnered with Superior Farms, a slaughterhouse, to evaluate their targeted genotyping panel, Flock54. Flock54 is a single nucleotide polymorphism (SNP) panel containing 956 markers for assigning pedigree and includes markers linked to quantitative trait loci and/or known single gene causative markers to aid in disease management and fecundity scoring. Ear notch samples were collected from 2,963 animals for analysis. This included 305 total sires as well as their progeny, 989 female lambs and 1,669 male lambs, which were marketed. Nine lambs were positive at a fecundity marker. No other notable results were found from the Flock54 panel. Genomic data was used to ascertain prolific sires on every ranch; however, ram to ewe ratio altered the influence that a prolific sire had on a lamb crop. The lowest ram to ewe ratio was 1:10. Parentage results from this ranch reports the following progeny metrics: Average: 9.9 males (±12.5); Median: 4 males; Max: 61 males, minimum 1 male. In contrast, the greatest ram to ewe ratio was 1:50. Parentage results from this ranch reports the following progeny metrics: Average: 51.9 (± 41.7); Median: 43.5; Max: 135; Minimum: 4,524 carcass samples from terminal lambs at two ranches were processed at Superior Farms` plant and assessed with a USDA inspected camera grading system. Progeny contemporary group deviations were calculated for hot carcass weight, yield grade, ovine cutability calculation (OCC), and OCC yield. After coupling carcass metrics with USDA reported prices, we identified prolific sires within the flock that garnered significantly higher and lower dollar merit at slaughter. A two-tailed Student`s T-test was used on the dollar deviation of edible product sold to identify if there was a statistically significant difference (P-value < 0.05) between a given ram`s progeny and the rest of the progeny slaughtered. We found that twenty-three out of the forty-three rams with progeny from one ranch had a statistically significant dollar deviation difference with a T-value greater than 2.0167. For the other ranch, we found that nineteen out of the thirty-five rams with progeny had a statistically significant difference with a T-value greater than 2.0301.