藏山羊若干行为观察研究

对全放牧藏山羊若干行为进行了昼夜连续24小时跟踪观测研究。结果表明,藏山羊昼夜采食时间为541.37±93.65分。反刍为280.21±67.59分,睡眠为173.30±45.92分,游走为136.15±62.79分,站立为133.35±34.88分,其他行为占175.62±53.18分。采食、游走、站立及其他行为多发生在白天,反刍和睡眠多在夜间。反刍与采食的时间比例为0.52:1。藏山羊母性较强,好喜戏和觅群,少争斗。此外,藏山羊还有搔痒、打喷嚏、啃食异物等异常行为。研究结果,可供藏山羊的培育和饲养管理作为参改。     

Halothane induced vasomotion of coronary, renal and iliac arterial rings in malignant hyperthermia susceptible swine.

Animals were identified as porcine malignant hyperthermia susceptible by halothane testing and were slaughtered at 90 kg of body weight. Coronary, renal and iliac arteries were isolated, dissected and 5 mm rings were mounted in 20 mL organ baths with modified Krebs solution maintained at 37 degrees C and oxygenated with 95% O2, 5% CO2. Halothane at 0%, 0.5%, 2% and 5% concentration was bubbled in the organ baths and mechanical responses were recorded over a period of 25 min. Halothane free arteries remained quiescent and the arteries from the halothane sensitive and from the halothane resistant groups reacted similarly. All arteries in the presence of halothane responded with an initial contraction of short duration followed by a relaxation and both phenomena occurred in a concentration-dependent fashion. The iliac artery was the most sensitive to halothane and responded to 0.5% concentration while coronary and renal arteries maintained the resting tension of 4 g. These results demonstrate that vascular smooth muscle, like skeletal muscle and unlike respiratory smooth muscle, has a direct pharmacological response to halothane. These observations led to the postulate that halothane by its transient but significant vasoconstrictive action could be a contributing factor to initiate the fulminant reactions occurring in malignant hyperthermia.     

Effect of pharmacological concentrations of zinc oxide with or without the inclusion of an antibacterial agent on nursery pig performance

A study involving nine research stations from the NCR-42 Swine Nutrition Committee used a total of 1,978 crossbred pigs to evaluate the effects of dietary ZnO concentrations with or without an antibacterial agent on postweaning pig performance. In Exp. 1, seven stations (IA, MI, MN, MO, NE, ND, and OH) evaluated the efficacy of ZnO when fed to nursery pigs at 0, 500, 1,000, 2,000, or 3,000 mg Zn/kg for a 28-d postweaning period. A randomized complete block experiment was conducted in 24 replicates using a total of 1,060 pigs. Pigs were bled at the 28-d period and plasma was analyzed for Zn and Cu. Because two stations weaned pigs at < 15 d (six replicates) and five stations at > 20 d (18 replicates) of age, the two sets of data were analyzed separately. The early-weaned pig group had greater (P < 0.05) gains, feed intakes, and gain:feed ratios for the 28-d postweaning period as dietary ZnO concentration increased. Later-weaned pigs also had increased (P < 0.01) gains and feed intakes as the dietary ZnO concentration increased. Responses for both weanling pig groups seemed to reach a plateau at 2,000 mg Zn/kg. Plasma Zn concentrations quadratically increased (P < 0.01) and plasma Cu concentrations quadratically decreased (P < 0.01) when ZnO concentrations were > 1,000 mg Zn/kg. Experiment 2 was conducted at seven stations (KY, MI, MO, NE, ND, OH, and OK) and evaluated the efficacy of an antibacterial agent (carbadox) in combination with added ZnO. The experiment was a 2 x 3 factorial arrangement in a randomized complete block design conducted in a total of 20 replicates. Carbadox was added at 0 or 55 mg/kg diet, and ZnO was added at 0, 1,500, or 3,000 mg Zn/ kg. A total of 918 pigs were weaned at an average 19.7 d of age. For the 28-d postweaning period, gains (P < 0.01), feed intakes (P < 0.05), and gain:feed ratios (P < 0.05) increased when dietary ZnO concentrations increased and when carbadox was added. These responses occurred in an additive manner. The results of these studies suggest that supplemental ZnO at 1,500 to 2,000 mg Zn/kg Zn improved postweaning pig performance, and its combination with an antibacterial agent resulted in additional performance improvements.     

Identification of pathogenic Leptospira strains in tissues of a premature foal by use of polymerase chain reaction analysis.

Studies were carried out to determine the cause of death in a prematurely born Thoroughbred foal that died 24 hours after birth. Necropsy revealed gross lesions suggestive of septicemia. A commercial Leptospira polymerase chain reaction (PCR) assay designed to specifically amplify the hemolysis-associated protein 1 (hap1) gene present only in pathogenic Leptospira strains detected the presence of Leptospira DNA in various tissues of the foal. Histologic examination of lung, liver, kidney, and myocardium revealed numerous spirochetes in Warthin-Starry-stained tissue sections. Results of PCR analysis and histologic examination suggested a leptospiral infection in the newborn foal. At the moment of death, the infection coexisted with a streptococcal-associated aspiration bronchopneumonia and postpartum septicemia. These findings indicate that the PCR assay based on the amplification of the hap1 gene represents a useful tool for specific detection of pathogenic leptospira in field samples taken from horses.     

Current therapies in exotic animal oncology.

The majority of information on oncology therapies has been reported in humans, canine, and feline patients, and laboratory animals with experimentally induced tumors. A variety of treatments,including radiation therapy, chemotherapy, photodynamic therapy, and others have been used with exotic animals. There are many species of exotic pets, and anatomic differences, as well as husbandry and nutritional requirements, must be taken into account to provide optimal care. By providing a broad overview of therapies and considerations for treatment, this article is intended to provide the practitioner with an overview of approach and options when addressing oncology cases in exotic animals.