BONUS SPRING SUMMER 2025

within 24 hours in some cases. The disease typically occurs when there is an overgrowth of C. perfringens in the intestine, often triggered by factors such as sudden dietary changes, handling or transport stress, dramatic changes in weather, or underlying intestinal damage. • Rapid drop in weight before death Affected chicks often stop eating and drinking • In some cases, chicks suffered from diarrhea • Dehydration and weight loss • Extensive inflammation of the gastrointestinal tract Ostrich chicks with enteritis display the following: Figure 1: Normal intestines of an ostrich chick (control group). Figure 2: Highly inflamed intestines with clear signs of necrosis from an ostrich chick that died from enteritis. Farmers often refer to chicks as having “Rooiderm”. Microbiome diversity and chick survivability A study done in 2020 through the Western Cape Department of Agriculture on gut dysbiosis and the microflora of juvenile ostrich chicks revealed the importance of a healthy and diverse gut microbiome for healthy, fit animals. Figure 5: Effect of age and disease status on alpha diversity across intestinal regions. Figure 5 above (Source: Videvall, E., et al. Microbiome [2020]) shows the alpha diversity during development in the ileum, caecum, and colon. Control (healthy) birds are shown in blue and diseased birds in red. The term alpha diversity refers to the diversity of microbial species within a single sample or environment, such as the gut microbiome. It provides a measure of the richness (number of species) and evenness (distribution of species abundance) within a given microbiome. The deceased chicks had greatly reduced microbial diversity in all three gut regions in comparison to the healthy control ostrich chicks. Higher alpha diversity is often associated with a healthy, more resilient gut. This is because microbial diversity indicates the stability and complexity of microbial communities, which are essential for digestion, immunity, and pathogen resistance. Figure 3 & 4: Further signs of hemorrhage in the front lobe of the liver can be noted, as well as yellow necrotic foci in liver. www.agribonus.co.za Spring/Summer 2025 BONUS 23