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Treatment with the synthetic glucocorticoid dexamethasone sodium phosphate increased the feed intake of sheep within 24 h. A single treatment with the longer-acting compound dexamethasone trimethylacetate had a slower effect, but resulted in improved feed intake and enhanced body weight gain over a period of 7 to 14 days. Treatment was effective in sheep housed individually and in sheep penned in groups. The improvement in body weight gain disappeared 15 to 20 days after a single treatment, but in most studies treated sheep had less variability in weight change than untreated sheep at this time. A statistically significant increase in body weight gain was observed in 8 of 11 trials; in the other 3 trials, it appeared that the feed intake of the untreated sheep was already maximal. Wethers treated with dexamethasone trimethylacetate on arrival at an assembly point for live export arrived in the Middle East 23 days later with a lower mean weight loss, partly because fewer sheep lost a significant amount of weight. 相似文献
75.
Habib M.R. Rashid M.H. Islam M.A. Majumder S. Islam K.M.S. Ahmed S. Alam M.S. Vargas-Bello-Pérez E. 《Tropical animal health and production》2018,50(4):889-895
Tropical Animal Health and Production - The objective of this study was to monitor the changes in growth, dry matter intake, and blood profiles (nutrition and reproductive hormones) of dairy... 相似文献
76.
Rahman M. Motiur Yasushi Furukawa Isao Kawata Mohammed Mahabubur Rahman Mahbubul Alam 《Journal of Forest Research》2006,11(2):89-97
Empirical information regarding the role of homestead forests in household economy is essential in understanding the importance
of these resources. Identification of the factors that affect homestead forest production and understanding forest owners'
attitudes toward key forest management issues have great significance in making appropriate policy responses to manage these
resources on a sustainable basis. In Bangladesh, homestead forests are claimed to play an important economic role in rural
livelihoods, but no reliable quantitative information exists. This study was undertaken to investigate the role of homestead
forests in the household economy, examine if forest production and income vary across landholding size classes, to explore
the relationships of homestead forest production with species richness, education level, and household size, and to assess
the attitude of homestead forest owners toward key forest management issues. Results show that homestead forests contribute
15.9% of the household income and generate 51.4 man-days of employment per household per year. Production of homestead forests
significantly varies across landholding size classes. It was observed that forest production depends significantly on species
richness of homestead forests and the education level of forest owners. However, no such relationship was found between forest
production and household size. The study revealed that farming families depend more on forest income than nonfarming families.
Attitudes of forest owners toward key forest management issues differ significantly across landholding size classes. For example,
although the majority of the forest owners prefer fruit species to timber species, the percentage of respondents decreased
as the landholding size class increased, while the opposite trend was observed for timber species. The findings of this study
suggest that diversification of forests and extension of education amongst forest owners would improve forest production.
Furthermore, forest policy should address the concerns of the forest owners in different landholding classes and focus on
their specific requirements to enhance sustainable forest management. 相似文献
77.
Carlton WK Gump B Fugelsang K Hasson AS 《Journal of agricultural and food chemistry》2007,55(14):5620-5625
An analytical method was developed to quantify levels of acetaldehyde in wine samples. The method utilizes headspace solid-phase microextraction with on-fiber derivatization using O-(pentafluorobenzyl)hydroxylamine and quantification by gas chromatography with flame ionization detection. The technique showed good sensitivity and reproducibility in samples of Chardonnay, Petite Sirah, and Merlot wines containing acetaldehyde at levels below the sensory threshold (40-100 ppm). The method was used to monitor acetaldehyde concentrations during the micro-oxygenation of Merlot wine in a 141 L pilot-plant experiment and a 2400 L full-scale study. In both experiments, levels of acetaldehyde remained constant for several weeks before increasing at rates of the order of 1 ppm/day. Variations in the levels of acetaldehyde present are discussed within the context of the underlying chemical reactions. 相似文献
78.
Ten multiparous crossbred local Zebu cows were randomly divided into two nutritional groups (A and B) to determine the effect of urea-molasses-mineral block supplementation on body weight gain, milk production, and onset of ovarian cyclicity after calving. Both groups had farm rations daily, but the supplemented group (B) was provided with an additional diet daily of 250 g urea-molasses-mineral block. The cows in group A required 80-120 days (98.0 +/- 6.7 days) until peak milk progesterone concentrations and 60-80 days (72.0 +/- 3.8 days) were required for group B (p<0.05). Group B needed a shorter period for expression of standing estrus (91-101 days; mean 96.2 +/- 2.3 days) than group A [130-153 (141.6 +/- 4.6) days; p<0.01]. For groups A and B, body weight gain was 8.4 +/- 3.4 kg and 18.4 +/- 3.2 kg, respectively (p<0.01). The average milk production of groups A and B were 3.3 +/- 1.0 and 4.8 +/- 1.6 L/day, respectively (p>0.05). There was linear improvement in milk yield from Day 60 postpartum up to Day 90 of lactation in group B (supplemented). However, in group A, milk production decreased starting on Day 40 after parturition. 相似文献
79.
MR Fernández-Santos AE Domínguez-Rebolledo MC Esteso JJ Garde F Martínez-Pastor 《Reproduction in domestic animals》2009,44(2):212-220
We have approached the problem of refrigerated storage of epididymal sperm samples from red deer by comparing three options: storing the genital (testicles within the scrotum), diluting the semen in extender or diluting the semen in extender supplemented with an anti-oxidant. Twenty-nine pairs of testes were collected. Spermatozoa from one of each of the pairs were immediately recovered, and diluted to 400 × 106 sperm/ml in Tris-citrate-fructose with 20% egg yolk. Control group was stored as such, and Anti-oxidant group was supplemented with 0.8 m m vitamin C. The remaining epididymides and the diluted samples were stored at 5°C and spermatozoa were analysed at 0, 24, 96 and 192 h for: motility [computer-assisted semen analysis (CASA)], acrosomal integrity, sperm viability (eosine/nigrosine staining), normal tails and chromatin status [sperm chromatin structure assay (SCSA)]. In general, seminal quality decreased with storage time. Vitamin C supported progressive motility better at 24 h (median 42% vs 23% Control and 15% epididymis), reduced the incidence of tail abnormalities and protected chromatin. Storing the semen in the epididymis slowed down motility loss, but slightly increased the occurrence of tail abnormalities and viability was lower at 192 h. However, regarding chromatin status, sperm stored in the epididymis was protected similarly to those diluted in the medium supplemented with vitamin C. Although the differences between the three groups were small, there were some advantages in supplementing the extender with vitamin C. Besides, refrigerating the epididymis may be a good option when immediate processing is not available. 相似文献
80.
The 1H- and 13C-NMR spectral data of ovatodiolide (1), a diterpenoid from Anisomeles indica, and its anti-HIV activity are reported. 相似文献