Re-calculating the cost of coccidiosis in chickens.

Coccidiosis, caused by Eimeria species parasites, has long been recognised as an economically significant disease of chickens. As the global chicken population continues to grow, and its contribution to food security intensifies, it is increasingly important to assess the impact of diseases that compromise chicken productivity and welfare. In 1999, Williams published one of the most comprehensive estimates for the cost of coccidiosis in chickens, featuring a compartmentalised model for the costs of prophylaxis, treatment and losses, indicating a total cost in excess of £38 million in the United Kingdom (UK) in 1995. In the 25 years since this analysis the global chicken population has doubled and systems of chicken meat and egg production have advanced through improved nutrition, husbandry and selective breeding of chickens, and wider use of anticoccidial vaccines. Using data from industry representatives including veterinarians, farmers, production and health experts, we have updated the Williams model and estimate that coccidiosis in chickens cost the UK £99.2 million in 2016 (range £73.0-£125.5 million). Applying the model to data from Brazil, Egypt, Guatemala, India, New Zealand, Nigeria and the United States resulted in estimates that, when extrapolated by geographical region, indicate a global cost of ~ £10.4 billion at 2016 prices (£7.7-£13.0 billion), equivalent to £0.16/chicken produced. Understanding the economic costs of livestock diseases can be advantageous, providing baselines to evaluate the impact of different husbandry systems and interventions. The updated cost of coccidiosis in chickens will inform debates on the value of chemoprophylaxis and development of novel anticoccidial vaccines.

Studies on prevalence and histomorphology of Sarcocystis species infecting cattle in Andhra Pradesh, India.

The present study was carried out to determine the prevalence of bovine sarcocystosis and identify the different species of Sarcocystis cysts in cattle in different regions of Chittoor district, Andhra Pradesh. A total of 150 slaughtered cattle over a period of 1 year were examined both macroscopically and microscopically for the presence of Sarcocystis infection. Out of 150 slaughtered cattle examined, macroscopic sarcocysts were observed in nine cattle and were exclusively found in oesophagus. Examination of tissue samples collected from different predilection sites from each of 150 cattle by pepsin-HCl digestion method revealed presence of live banana shaped bradyzoites under light microscopy in 134 cattle. Six cattle that were positive by macroscopic examination were also positive by microscopic examination of tissues. The overall prevalence of Sarcocystis infection in cattle of Chittoor district was 91.33%. The prevalence of macroscopic and microscopic sarcocysts was 6.57 and 93.43% respectively. Statistically a significant relationship between the prevalence of infection among different age groups (P < 0.001) and no significant relationship (P > 0.001) between the prevalence of Sarcocystis infection in male (91.76%) and female (90.76%) cattle was observed. In both male and females the prevalence of Sarcocystis infection increased with age. Microscopically sections of tissues from cattle that were positive by tissue digestion technique revealed thin walled cysts (4.5 ± 0.5 µm) in 131 samples and thick walled cysts (0.5 ± 0.12 µm) in six cattle.