浅谈饲料分析实验课的教学与改革

为促进教与学的相互提高,进一步调动学生主动学习的积极性,提高学生实践的综合素质,结合我院的具体情况,从教学各个环节,总结并探讨了如何提高饲料分析实验课的教学质量,并提出了今后工作的几点改革设想.只有不断地改革创新,才能高品质、高质量地实现实践教学,才能培养出适应新世纪发展需要,具有实际开发和创新能力的人才.     

Some clinical, haematological and biochemical effects of four tranquilizers in camels (Camelus dromedarius)

Six healthy camels were treated with the tranquilizers propionyl promazine (Combelen), xylazine (Rompun), acepromazine (Calmivet) or chlorpromazine (Largactil) at single intramuscular doses of 0.5, 0.25, 0.1, or 3 mg/kg, respectively; and the onset, duration and degree of sedation produced by each drug was assessed for six hours. The effect of the treatments on some haematological and biochemical parameters was also studied. The onset and duration of action of the tranquilizers were 10 min and 2.1 +/- 0.5 h for propionyl promazine, 4 min and 3.1 +/- 0.4 h for xylazine, 5 min and 2.3 +/- 0.5 h for acepromazine, 7 min and 2.5 +/- 0.4 h for chlorpromazine, respectively. It was observed that 5-10 min after the administration of the four drugs, camels showed slight irritability, dropping of the lower lips and scratching of the nostrils against objects. During the first hour after medication camels showed frequent urination, defaecation and lacrimation. Xylazine seemed to be superior to the other three drugs in producing sedation. No significant effect on the rectal temperature or the respiratory rates of treated camels was seen after the administration of the four drugs. There were consistent, but statistically insignificant decreases (about 10 p. 100) in the haemoglobin concentration and erythrocyte counts of camels one hour after treatment with the tranquilizers. The four drugs, particularly xylazine and propionyl promazine produced significant hyperglycaemia, but did not alter significantly the plasma concentration of urea or activity of aspartate aminotransferase.     

Appropriate Timing of Supplemental Feeding for Production of Nile Tilapia, Silver Carp, and Common Carp in Fertilized Polyculture Ponds

In an attempt to identify appropriate times for initial application of supplemental feed in polyculture fertilized fish production earthen ponds, a study was conducted for 19 wk to establish the growth performance, yield, survival, and body composition of Nile tilapia, common carp, and silver carp as influenced by four different feeding regimens (treatments). The four treatments were: 1) supplemental feeding beginning at onset of the experiment (T-I) (control treatment); 2) 6-wk delay of feeding after fish stocking (T-II); 3) 13-wk delay of feeding after fish stocking (T-III), and 4) no supplemental feed application (T-IV). Two ponds were assigned to each treatment and each pond was stocked with a similar number and weight of each fish species. A commercial pelleted fish feed (25% protein) was used to feed fish in T-I, T-II, and T-III at 3% of their body weight, twice a day. At the end of the experiment, fish species (except for silver carp) in T-II showed weight gain, growth rates, and yields significantly higher than fish in T-III or T-IV. Also, the total fish production and net profit in T-II were significantly higher than in T-III or T-IV. Fish species in T-II showed weight gain, growth rates, survival rates, and yields similar to those of T-I (control treatment) with no significant differences. The amount of feed consumed by fish in T-II was reduced by approximately 7.3% compared to that consumed by fish at T-I. Moreover, there was increase in th net profit in T-II by 4.8% over that achieved in T-I. Therefore, T-II appears to be the most appropriate among the tested feeding treatments and recommended for use in order to achieve the best growth, production, and net profit.     

Effect of furazolidone and nitrofurazone on egg production, on plasma luteinising hormone and on prolactin concentrations in turkeys

1. Furazolidone or nitrofurazone were given orally to laying turkeys at doses of 7.5, 15 or 30 mg/kg for 7 d. Plasma concentrations of luteinising hormone (LH), prolactin (PRL) and egg production were measured before, during and after treatment. 2. Both drugs produced dose-dependent decreases in LH concentration which were statistically significant at doses of 15 and 30 mg/kg. Plasma PRL concentration was significantly increased in birds receiving 15 or 30 mg/kg of nitrofurazone, and tended to increase in the other treated groups, but this was not statistically significant. 3. Egg production was lowered in a dose-dependent manner by both drugs. However, nitrofurazone appeared to be more potent in reducing egg production than furazolidone. 4. Birds given 15 mg/kg of either drug were injected intramuscularly with luteinising hormone releasing hormone (LHRH) at a dose of 5 micrograms/kg and blood was collected immediately before and 30 min after LHRH administration. 5. Nitrofurazone significantly reduced the rise in LH induced by LHRH. Seven days after withdrawing the drug, the LHRH-induced LH release was not significantly different when compared to that in the control group or that seen on day 7 of treatment.     

Effect of feeding on the fate of orally administered phenylbutazone, trimethoprim and sulphadiazine in the horse

Phenylbutazone, sulphadiazine and trimethoprim were administered to three horses on two occasions, recently fed and unfed, and the effect of feeding on the pharmacokinetics of the three drugs assessed. The mean peak concentrations of phenylbutazone and trimethoprim were reduced by feeding by 34 and 75 per cent, respectively. The pharmacokinetics of sulphadiazine were not significantly affected.