The consequences of prolonged environment-induced heat stress (EIHS) on heart health are largely unknown. We discovered that a 24-h exposure to environmental conditions sufficient to cause EIHS resulted in cardiac edema and histopathologic changes in the right and left ventricles. Furthermore, among other biochemical changes, EIHS increased autophagic flux and caused endoplasmic reticulum stress. These data raise the possibility that thermic injury, even when insufficient to cause heat stroke, can damage the myocardium.

Astroviruses infect mammals and birds resulting in either gastroenteritis, neurologic disease, or asymptomatic infection. Porcine astrovirus 4 (PoAstV4) has previously been detected in the upper respiratory tract of pigs with clinical respiratory disease; however, proof of respiratory tract infection and association of the virus with respiratory pathology have not been shown. In this retrospective study of young pigs with clinical respiratory disease of unknown etiology, PoAstV4 was detected with RNA in situ hybridization in lesions consistent with epitheliotropic viral infection in 85 of 117 pigs. This is the first report associating an astrovirus with respiratory pathology.

Heat stress is a global threat to human health and agricultural production. We demonstrated that following 7 days of heat stress, skeletal muscle from females was more susceptible to oxidative stress than muscle from males in a porcine model, despite cooler muscle temperatures. The vulnerability to heat stress-induced oxidative stress in females may be driven, at least in part, by decreased antioxidant capacity and calcium dysregulation.

Objective: We present a retrospective evaluation of small ruminant reproductive loss investigations performed at the Iowa State University Veterinary Diagnostic Laboratory (ISUVDL) with comprehensive characterization of submission components, etiologies of reproductive losses, and assessment of factors contributing to diagnostic success. Methods: Data from 354 small ruminant abortion submissions received at ISUVDL between January 1, 2019, and December 31, 2023, were evaluated for history completeness, sample inventory, gross and histologic lesions, culture yield, and molecular testing results. Univariate logistic regression models were employed to assess associations between achieving a definitive diagnosis and specific submission variables. Results: A definitive etiology for pregnancy wastage was achieved in 50.3% of caprine and 64.6% of ovine submissions. Bacterial abortions represented the largest etiologic category, with Campylobacter jejuni accounting for the greatest share of bacterial infections (36.2% of bacterial abortions and 10.7% of all cases). Toxoplasma gondii was the single most frequently diagnosed abortifacient agent (15%), while fungal and viral abortions were rare (< 2%). Sampling and diagnostic completeness, with the inclusion of both fetus and placenta (OR, 2.61), and performance of histopathology, culture, and molecular screening in tandem (OR, 2.03) were found to have the greatest positive impact on diagnostic outcomes. Conclusions: Diagnostic outcomes are optimized by complete sampling and testing, with priority placed on comprehensive molecular screening for pathogens that are highly significant for herd health. Clinical Relevance: This retrospective provides an in-depth summary of small ruminant abortion case data from submissions received at ISUVDL and makes recommendations for improving diagnostic outcomes in reproductive loss investigations.