Strongyloides papillosus causes sudden death in weaned calves on New York dairies

Abstract

CASE DESCRIPTION Outbreaks of sudden death in apparently healthy weaned dairy calves due to Strongyloides papillosus parasitism were diagnosed on 2 separate and independent New York (NY) dairies. CLINICAL FINDINGS Most calves were found dead; however, 1 calf observed while dying showed signs of tachycardia, tachypnea, vocalization, and convulsions shortly before death. In 6 affected heifers that underwent post-mortem examination, precocious bilaterally symmetric mammary gland enlargement was seen. A portion of their parasitized living cohorts also demonstrated similar mammary gland enlargement. A diagnosis of S papillosus hyperinfection was made based upon the presence of high numbers of S papillosus ova in feces, and confirmation by S papillosus–specific PCR assays. Consistent histopathological findings in affected calves included generalized mammary gland vascular congestion, interstitial edema and hemorrhage with ductal hyperplasia. Mild multifocal cardiomyocyte degeneration was found in 5 of 14 calves examined. Factors believed to contribute to the parasite’s environmental amplification and host hyperinfection included group housing on wood shavings and high environmental temperatures and humidity. TREATMENT AND OUTCOME Treatment of calves with doramectin pour-on stopped mortality and resolved the udder enlargement. CLINICAL RELEVANCE Similar outbreaks have previously been described in Japan and South Bohemia (Czech Republic), where researchers hypothesized that sudden death may be due to fatal arrhythmia caused by a parasite-associated cardiotoxin. This report highlights the importance of including S papillosus among the differential diagnoses for sudden death alone or together with precocious udder enlargement in calves kept in confinement housing.

Eukaryotic Infections in Dairy Calves: Impacts, Diagnosis, and Strategies for Prevention and Control

“…These include diarrhea, weight loss, decreased feed efficiency, and reduced growth rates. 132 Furthermore, the migration of larvae in the body of host can cause tissue damage, leading to inflammation and secondary infections. The severity of clinical signs can vary based on factors such as age of the calf, nutritional status, and overall health.…”

“… 129 Several factors contribute to the prevalence of S. papillosus infection in dairy calves, including management practices, environmental conditions, and host susceptibility. 132 …”

“…129 Several factors contribute to the prevalence of S. papillosus infection in dairy calves, including management practices, environmental conditions, and host susceptibility. 132 Accurate diagnosis of S. papillosus infection is crucial for effective management. Various diagnostic methods are available, including fecal egg counts, larval culture, and serological tests.…”

The population genetics of Strongyloides papillosus in Pakistani goats revealed by whole genome sequencing

“…Strongyloides (Rhabditida, Strongyloididae) is a genus of gut parasitic nematode that infects a wide variety of terrestrial vertebrates. Strongyloides papillosus has been reported to parasitise sheep, goats, and cattle and can be experimentally maintained in rabbits (Pinn et al ., 2022). However, the species identity of Strongyloides infecting these host species has been questioned.…”

“…S. papillosus can cause diarrhoea, dehydration, anorexia, anaemia and malnutrition, especially in young animals (Thamsborg et al ., 2017). High intensity infections can cause serious strongyloidiasis, which can be fatal (Pinn et al ., 2022). Interdigital dermatitis and fatal ventricular fibrillation resulting from S. papillosus infection have been described in sheep and cattle (Turner et al ., 1960; Nakamura et al ., 1994; (Thamsborg et al ., 2017).…”