Evaluation of vitamin A gut loading in black soldier fly larvae (Hermetia illucens)

Updates for Reptile Pediatric Medicine

The health of hatchling, juvenile, and young adult reptiles continues to be plagued by historic nutritional deficiencies, old and emerging infectious diseases, and more recent phenotype-selective congenital abnormalities that impact welfare. Knowledge of mating seasonality, average egg counts, gestation times, and age and/or size for sexual maturity is necessary to help guide best practices for care of pediatric reptiles. Calcium, vitamin D3, and ultraviolet B (UVB) lighting recommendations vary in effectiveness amongst different species and can change with age. Phenotype-selective color patterns for spider ball pythons and scalation pattern for bearded dragons have resulted in vestibular disease, and increased evaporative water loss, respectively. Salmonellosis remains the most reported zoonotic disease for captive reptiles in the United States, despite improvements in client education and improvements in captive reptile husbandry.

Transgenic black soldier flies for production of carotenoids

The black soldier fly (BSF), Hermetia illucens, has gained traction recently as a means to achieve closed-loop production cycles. BSF can subsist off mammalian waste products and their consumption of such waste in turn generates compost that can be used in agricultural operations. Their environmental impact is minimal and BSF larvae are edible, with a nutritional profile high in protein and other essential vitamins. Therefore, it is conceivable to use BSF as a mechanism for both reducing organic waste and maintaining a low-impact food source for animal livestock or humans. The main drawback to BSF as a potential human food source is they are deficient in fat-soluble vitamins such as Vitamins A, D, and E. While loading BSF with essential vitamins may be achieved via diet-based interventions, this undercuts the goal of a closed-loop as specialized diets would require additional supply chains. An alternative is to genetically engineer BSF that can synthesize these essential vitamins. Here we describe a BSF line that has been engineered with the two main carotenoid biosynthetic genes, CarRA and CarB for production of provitamin carotenoids within the Vitamin A family. Our data describe the manipulation of the BSF genome to insert transgenes for expression of functional protein products.

Reptile Dermatology

Reptiles are being presented more frequently to veterinarians because they increase in popularity. As with domestic pets, dermatologic conditions are common findings in captive reptiles and can be associated with husbandry and nutritional deficiencies, infectious diseases, and neoplasia. To have success with these cases, it is important to take a stepwise and strategic approach, starting with a thorough anamnesis and physical examination. From there, diagnostic tests should be pursued, with an understanding of the limitations of each diagnostic test. By understanding these limitations, the veterinary scientist can determine the best path to a diagnosis and treatment for the case.

Establishing and Maintaining an Etruscan Shrew Colony

The Etruscan shrew (Suncus etruscus) is one of the smallest mammals on earth and is used in many fields of research, including physiology, behavioral science and neuroscience. However, establishing and maintaining a breeding colony of this species in the laboratory can be challenging, as it requires specific husbandry conditions that greatly differ from those of more common laboratory species such as mice or rats. Over the past 15 y, we have successfully established a long-term thriving colony of 150 to 200 animals originating from 36 founders. The colony shows longer life expectancy and larger litter sizes than wild conspecifics. Breeding occurs year-round, independent of seasons, and a breeding pair can regularly produce 2 to 6 offspring with an average life expectancy of more than 3 y. The shrews are housed in glass or plastic enclosures on a specific soil-sand-mixture bedding and are provided with hideouts and nesting material consisting of moss, wood, or bark. Due to their high basal metabolic rate, the shrews require food intake greater than their body weight per day, can hunt arthropods as large as themselves, and cannot survive more than a few hours without food. Live feed such as crickets or mealworms is crucial and must be provided daily or, at the very least, every 2 d. Although our husbandry practices have constantly been adapted and refined, shrew husbandry remains challenging, and great care is necessary to meet the specific needs of this species. Here, we describe the establishment of a long-term stable colony of Etruscan shrews in a research animal facility and the specific husbandry requirements for animal wellbeing.