This report describes a huge gastric trichobezoar in a 12-year old male captive African lion (Panthera leo) leading to gastric perforation, fatal peritonitis and death. At necropsy, the stomach seemed firm, highly distended and filled with a giant mass weighted 3800 grams. A big perforation was identified in the antrum which caused severe pyoperitoneum, septic shock and death. Restricted physical activity at nights, whole carcasses feeding, lack of fiber supplement or laxatives and repetitious diet were the major risk factors for trichobezoar formation in this case. Trichobezoar should be considered as a common gastrointestinal disease in captive wild cats, so nutritional and medical preventive regimen is highly recommended for lions in zoos. Determining the common causes of morbidity and mortality of wild felines housed in zoological collections will provide insights that contribute to their improved care, health, and medical management in captivity and ultimately affect the sustainability of these species in the wild.

Acquired immunity is reported only in vertebrates. However, nowadays, the available evidence shows that a kind of quasi-specific immunity and also an immune memory exists in crustaceans. This process is explained by several mechanisms, the most important of which are some humoral immune factors such as lectin and Dscam. Down syndrome cell adhesion molecules (Dscam) are kinds of pathogen-dependent molecules that are produced during exposure of some invertebrates to pathogens (antigens). Vaccine-like agents may be synthesized to act as activators and activate this immune mechanism in shrimp through antigens, and consequently, make a kind of immunogenicity. It is not as accurate as vertebrates’ immune system and the secretion of antibodies and can lead to relatively specific immunizations in crustaceans. Nevertheless, the corresponding immunization practically decreases the economic losses of the shrimp industry. Hence, we recommend the health management of the shrimp farms should not focus only on the production of specific pathogen-free larvae by relevant institutions or the implementation of biosecurity guidelines by farmers, but in order to prevent the infectious agents in shrimp farms, the novel solutions in this context should be developed.