Acceptance by stoats (Mustela erminea) of 1080 (sodium monofluoroacetate) in small-volume baits and its effect on behaviour and time to death.

AIMS: To assess whether stoats (Mustela erminea) would eat small baits containing 0.1% sodium monofluoroacetate (1080); whether they would die from it; how long it would take to kill them; and to document the behaviour of 1080-intoxicated stoats. METHODS: Stoats were offered 1-g baits of two semi-fluid formulations containing 0.1% 1080, presented in open dishes, and their subsequent behaviour was monitored by video and direct observation. Muscle samples from stoats that died were analysed for 1080 residues. RESULTS: There was no significant difference between two types of bait with regard to acceptance, mortality, and time to death, and behavioural effects were similar; consequently, results from the two types of bait were combined. Twelve of 14 stoats offered the baits ate them voluntarily, and a 13th licked bait off its fur; all 13 died between 1 h 15 min and 4 h 7 min (mean 2 h 38 min) later. At first (range 29 min - 2 h 7 min, mean 1 h 1 min), their behaviour appeared to be normal. Ataxia and hyperactivity were the first behavioural signs of poisoning, and lasted 2 min - 1 h 40 min (mean 26 min). This was followed by recumbency with convulsions and rapid breathing (range 16 min to 2 h, mean 58 min), then recumbency with limited activity and progressively shallow breathing prior to death (range 1-51 min, mean 33 min). Stoats became non-responsive to a light being turned on, or to touch once recumbency became sustained. Residues of 1080 were found in muscle tissue of all 13 dead stoats, at concentrations ranging from 0.075 microg/g in a 287-g male that died 4 h 7 min after eating only 0.74 g of bait, to 2.5 microg/g in a 254-g female that died 2 h 42 min after taking a whole 1-g bait. CONCLUSION: Stoats will voluntarily take small (1-g) baits containing a lethal dose of 1080 at 0.1%, and die from it comparatively rapidly for a mammalian carnivore.

Effect of methadone addiction on glucose metabolism in rats.

Female albino rats were exposed to methadone over a 35-day period by addition of the drug in their drinking water. The final dose of the drug was 1.8 mg/kg body weight per day. After this period, the drug was withdrawn from some animals for 30 days (postexposure). Compared to unexposed controls, serum glucose levels rose during exposure and returned to control levels postexposure. Oral glucose tolerance tests showed impairment in 35-day drug-exposed animals compared to controls and postexposure. The activities of three key enzymes of glycolysis and three key enzymes of gluconeogenesis were measured in liver during and at the end of the exposure period, as well as postexposure. Compared to unexposed controls and postexposure, specific activities of two glycolytic enzymes in livers of exposed animals-hexokinase and phosphofructokinase 1-were significantly reduced, whereas the activity of a third glycolytic enzyme-pyruvate kinase-was unchanged. The specific activities of two gluconeogenic enzymes-glucose-6-phosphatase and fructose-1,6-biphosphatase-were significantly elevated in the drug-exposed animals compared to controls, whereas the activity of a third enzyme-phosphoenolpyruvate carboxykinase-was unchanged. These data indicate that methadone addiction produces a metabolic state similar to insulin-resistant diabetes.

Detection of rotavirus and coronavirus shedding in two beef cow herds in Idaho.

Fecal samples were taken at the time of pregnancy examinations and at parturition from two beef herds. They were also taken from sick calves at the onset of disease, and from 25% of the healthy calves at 15 days of age. All fecal samples were examined by electron microscopy for viruses.Four cows in herd A were detected excreting coronavirus, one at the time of the pregnancy examinations and three at parturition. The first cow was removed from the herd and the others calved at the end of the season. There were no sick calves.No cows in herd B were detected excreting virus at the time of pregnancy checks, but fourteen coronavirus and two rotavirus carrier cows were found at parturition. All but two calves sampled had large numbers of virus particles in their feces. Clinical illness was associated with dams shedding virus and with nightly low temperatures.

Ovariectomy as treatment for granulosa cell tumor in a heifer.

A granulosa cell tumor in a 15-month-old heifer was associated with abnormal udder development, relaxation of the pelvic ligaments, and nymphomanic behavior. After surgical removal of the tumor, the anatomic changes were reversed, and the nymphomanic behavior subsided. The heifer conceived 3 times thereafter and became a productive dairy cow. In previously reported cases of granulosa cell tumor, ovariectomy was unsuccessful in returning the cow to normal breeding.