Anesthesia and analgesia of ornamental birds

Pet birds are frequently viewed as difficult patients for anaesthesia. The present paper revises the current anaesthetic procedures for injectable and inhalant anaesthetics. Currently the method of choice for the anaesthesia of pet birds is the isoflurane inhalation anaesthesia. Special emphasis is given to the preanaesthetic preparations. Fasting is shorter for pet birds than for mammals. Anaesthetized birds are at special risk for hypothermia. Methods for the prevention of heat loss are given. The use of analgesics are recommended both for welfare reasons but also because of the possibility to reduce the concentration of inhalation anaesthetics and therefore the amount of possible exposure of personnel to waste gases.     

Immunological basis of differences in disease resistance in the chicken

Genetic resistance to diseases is a multigenic trait governed mainly by the immune system and its interactions with many physiologic and environmental factors. In the adaptive immunity, T cell and B cell responses, the specific recognition of antigens and interactions between antigen presenting cells, T cells and B cells are crucial. It occurs through a network of mediator proteins such as the molecules of the major histocompatibility complex (MHC), T cell receptors, immunoglobulins and secreted proteins such as the cytokines and antibodies. The diversity of these proteins that mainly is due to an intrinsic polymorphism of the genes causes phenotypic variation in disease resistance. The well-known linkage of MHC polymorphism and Marek's disease resistance difference represents a classic model revealing immunological factors in resistance differences and diversity of mediator molecules. The molecular bases in any resistance variation to infectious pathogens are vaguely understood. This paper presents a review of the major immune mediators involved in resistance and susceptibility to infectious diseases and their functional mechanisms in the chicken. The genetic interaction of disease resistance with production traits and the environment is mentioned.     

Effects of testicular biopsy in clinically normal bulls

OBJECTIVE: To determine whether testicular needle biopsy is detrimental to testicular function in clinically normal bulls. DESIGN: Prospective study. ANIMALS: 6 mixed-breed mature bulls. PROCEDURE: A randomly selected testicle from each bull was biopsied with a 14-gauge needle biopsy instrument. Bulls were then evaluated over a 90-day period for changes in scrotal temperature and thermal patterns, ultrasonographic appearance, and quality of spermatozoa. At the end of the 90-day study, bulls were castrated, and testicles were examined grossly and histologically. RESULTS: Changes were detected in scrotal temperatures and thermal patterns and in the breeding soundness examination results during the first 2 weeks of the study. However, there were no long-term changes in semen quality over the course of the experiment. Hyperechoic areas were detected on ultrasonographic examination and corresponded to the areas of penetration by the biopsy instrument. Microscopic lesions that were indicative of testicular dysfunction were not found. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that testicular biopsy is a safe procedure in bulls. Testicular biopsy could possibly be used to further examine bulls that have less than satisfactory results for breeding soundness examinations.     

Control of heifer mastitis by nutrition

Nutritional factors that are linked to mastitis in the mature dairy cow can be associated with mastitis in the first lactation cow as well. However, there may also be risk factors unique to the heifer due to differences in feeding management during rearing or pre-calving. Literature was reviewed to summarize current knowledge regarding links between heifer nutrition and mastitis with the potential to identify areas for future research. The preponderance of data relating nutrition and bovine mastitis involves selected micronutrients. Selenium and vitamin E enhance phagocytic activity and have been associated with decreased clinical mastitis risk. Copper has antioxidant functions and can reduce clinical mastitis in heifers. Zinc is implicated in maintaining the epithelial barriers to infection, but reports vary as to its role in udder health. Vitamin A and beta-carotene aid in maintaining the health of mucosal surfaces, and beta-carotene may also have antioxidant properties. Supplementation with vitamin A and beta-carotene has produced inconsistent results. Vitamin and mineral requirements of dairy heifers are generally influenced by growth rate and body weight relative to mature size, though little specific data is available. From a management standpoint, heifer rations should be supplemented where necessary, and a pre-fresh heifer diet is critical to assure that first lactation animals have adequate stores of minerals and vitamins. Adequate stores are necessary for transfer into colostrum by calving. Additional studies using field data and controlled studies are needed to further define the role of nutrition in animal health and in affecting specific mastitis-causing organisms.     

Veterinary practice, competition and advertising: 1985-1994

In 1985, members of the veterinary profession and four other professional groups in New Zealand were surveyed to establish their attitudes towards the developing commercialisation of their professions, and particularly towards advertising. This survey was repeated in 1988, and again in 1994. The results of the three surveys are presented in this paper. There was a sharp movement towards acceptance of advertising, and toward a competitive orientation in general, between 1985 and 1988, with a consolidation of these changes during the following 6 years. The acceptance of the idea of an openly competitive profession now has widespread support among veterinarians. Similarly, there is general support for the use of most kinds of informative advertising, with many practitioners viewing advertising as a business building tool, but with the advertising of fees remaining an area over which there is still considerable caution. Although clients are seen as more demanding than in the past, the client-practitioner relationship is still expected to be an enduring one. We suggest that, in view of the relaxed attitudes towards advertising that now exists among members of the veterinary profession, control of advertising should cease to be a concern to the profession.     

Squamous cell carcinoma originating from a cutaneous scar in a llama.

A nonhealing wound associated with a laceration in a 12-year-old llama was evaluated. Initial attempts at closure were unsuccessful and biopsy revealed scar tissue. Subsequent biopsies, 18 mo later, revealed squamous cell carcinoma with regional metastasis. This report describes squamous cell carcinoma, secondary to a traumatic wound in a llama.