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996.
Microcomputer systems were placed in three veterinary practices each serving three farms (bureau), and onto nine dairy farms (on-farm). Over a twenty-four week period, the utilization of the computer system and the DHM software was monitored. The on-farm system was more costly in terms of equipment and technical support effort, but the information was utilized to a greater extent than it was by the bureau participants who had invested more user time per cow. Note that actual time will vary with the software program used. The farmers indicated that they wished to have access to the information offered by the software. `Computer phobia' was not found to be a problem. The expectations of the computer system and its benefits generally remained high. In general, the information available through the microcomputer system and the DHM software was found to be useful to both the dairy farmers and the veterinarians in this study.  相似文献   
997.
1. Two environmentally controlled houses at 21°‐30°‐21°C (HT) and 21°C (LT) were used to study the effect of temperature on fatty acid composition of the abdominal fat of male and female broilers fed 13.8 and 13 MJ ME/kg diets and slaughtered at 34 and 54 d.

2. Extracts from the abdominal fat of 160 carcases and of the experimental foods were analysed for fatty acids by gas liquid chromatography.

3. Birds reared in HT had a significantly lower proportion of polyun‐saturated fatty acids (PUFA) in their abdominal fat between 34 and 54 d than birds in LT. The depot fat contents of oleic, linoleic and linolenic acids were all reduced by HT at 54 d.

4. For broilers slaughtered at 54 d, saturated fatty acid (SFA) content was much higher in females at high temperatures than in males while at low temperatures PUFA, especially linoleic, was much lower in males than in females.

5. Early finishing of broilers is advantageous from the viewpoint of fatty acid composition because the PUFA/SFA ratio declines significantly with age regardless of temperature.  相似文献   

998.
1. The effects of continuous infusion of 0.1, 1.0 and 10.0 mU/min/kg body weight of arginine vasotocin (AVT) or mesotocin (MT) on cardiovascular and thermoregulatory responses, on plasma osmolality and ionic composition and on plasma concentrations of AVT, MT, prolactin and aldosterone, were investigated in conscious White Leghorn cockerels.

2. Neither of the peptides, at any dose, affected cardiovascular functions, plasma ions and osmolality. Infusion of MT at the rate of 10 mU/min/kg body weight increased respiratory rate. Both peptides at doses of 1 and 10 mU/min/kg reduced the temperatures of the comb and shank but had no effect on the skin and cloaca.

3. Doses of 0.1 and 1.0 mU MT/mu/kg reduced plasma aldosterone and at 10 mU/min/kg increased plasma AVT. At any given dose MT had no effect on plasma prolactin. AVT at 0.1 and 1.0 mU/min/kg of AVT reduced plasma MT. AVT at 1.0 mU/min/kg increased plasma prolactin and at 10 mU/min/kg reduced plasma aldosterone.

4. During saline infusion, plasma MT was positively correlated with plasma AVT and negatively correlated with respiratory rate and cloacal temperature. Plasma AVT showed a positive correlation with plasma MT and aldosterone and a negative correlation with respiratory rate and skin temperature.

5. During saline infusion, there was no significant correlation between cardiovascular functions, or plasma osmolality and ionic composition and plasma MT or AVT.

6. The present study suggests that interrelationships between circulating concentrations of AVT and MT do exist and that AVT affects  相似文献   

999.
Six shipments totaling 3452 mummies of the blackmargined aphid,Monellia caryella (Fitch), parasitized withAphelinus perpallidus Gahan, were obtained by air freight during the years 1982-1985 from Texas A&M Research Center, El Paso, Texas. About two-thirds of the mummies did not yield parasites. A colony ofA. perpallidus was established in the laboratory. Under laboratory conditions the percentage of emerged parasites was higher than that in the imported mummies, and the parasite had very limited impact on the aphid population. Field releases of the parasite were made but no establishment ofA. perpallidus was observed through the years.  相似文献   
1000.
Cucumber Mosaic Virus, or Infectious Chlorosis, was found in alarming proportions in all the districts of Tamil Nadu on the ‘Robusta’ (Dwarf Cavendish) and ‘Poovan’ (Mysore) cultivais. The disease was transmitted only through suckers from the diseased gardens. Among the genotypes screened, the clones with ABB genomes showed complete field resistance.  相似文献   
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