Seasonal Variation in Nutritional Indices of Collared Peccaries in South Texas

Abstract

The prospect of using serum, urine, and fat parameters as nutritional indices in the collared peccary (Tayassu tajacu) was assessed relative to seasonal changes in dietary protein and energy intake. Animals were collected in the field every 2-3 months for 1 year. Seasonal variations occurred in blood urea nitrogen (BUN), potassium, calcium, alkaline phosphatase, cholesterol, total protein, globulin, albumin/ globulin ratio, creatinine, whole body/carcass weight, the kidney fat index (KFI), femur marrow fat, crude protein-digestible energy intake, and the urinary urea/creatinine ratio (P < 0.05). Of the indices examined, BUN and the KFI were most labile in response to changes in nutritional intake. The KFI varied with digestible energy, but variation was less than has been reported in more temperate species, which may reflect dissimilar physiological adaptations. Both crude protein and energy intake influenced BUN. Whole body weights, carcass weights, and dietary crude protein levels were greater (P < 0.05), but BUN concentrations were lower (P < 0.05), in pregnant vs. nonpregnant females. Chloride and cholesterol concentrations were greater (P < 0.05) in females than in males. Using physiological indices to monitor nutritional status of populations may aid in collared peccary management. J. WILDL. MANAGE. 49(1):57-65 The collared peccary occurs from northern Argentina to the southwestern United States (Sowls 1978) in habitats ranging from tropical to arid (Leopold 1959). Historically, the collared peccary has been hunted throughout its range for meat and hides. More recently, it has become an important big game animal in Texas and Arizona (Sowls 1978, Bissonette 1982). There are few published data pertaining to the nutritional status of free-ranging peccary populations or on the use of physiological parameters as indicators of nutritional condition. Physiological indices have been used to assess the nutritional status of various mammals (Kirkpatrick 1980). In several species, blood constituents, such as BUN, albumin, and cholesterol, and fat indices, such as femur marrow fat (FMF) and the KFI, vary with nutritional intake. Changes in the protein and energy content of an animal's diet can measurably influence such parameters. The objective of this study was to determine if seasonal variation in available forage, as indicated by changes in protein and energy content in stomach samples, would be reflected in blood serum, urine, and fat indices of collared peccaries. We thank S. C. Smith for laboratory assistance and F. C. Turley and J. B. Finley, Jr., for permission to collect peccaries on the Callaghan Ranch. This study was funded by the Noxious Brush and Weed Control Program, Coll. of Agric. Sci., Texas Tech Univ., and represents Ms. T-9-359.