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排序方式: 共有147条查询结果,搜索用时 31 毫秒
1.
Adult wethers (n = 750) were lot-fed for 13 days, 8 days or 3 days before a simulated voyage lasting 18 days to examine whether the period of lot-feeding affected the proportion of sheep that ate pelleted feed and their body weight change during simulated shipping. There was no significant difference in the proportion of non-feeders between treatment groups on days 7 and 14 of the voyage. Body weights were not significantly different between the treatment groups on days 14 and 18 of the voyage. Overall body weight loss, from the farm to the end of simulated shipping, was 4.08 kg (+/- 0.28, s.e.m.), 4.58 kg (+/- 0.28) and 4.51 kg (+/- 0.28) in sheep lot-fed for 13 days, 8 days and 3 days, respectively, and was not significantly different between treatments. It was concluded that lot-feeding for 13 days conferred no advantage in body weight or numbers of non-feeders compared with shorter periods in this study. 相似文献
2.
SR Cho SA Ock JG Yoo B Mohana kumar SY Choe GJ Rho 《Reproduction in domestic animals》2005,40(2):171-176
The present study was designed to examine the effects of cell-cycle synchronization protocols, such as confluent, roscovitine treatment and serum starvation, in bovine foetal fibroblasts on synchronization accuracy at G0/G1, viability, apoptosis, necrosis and ploidy for use as a nuclei donor. The cells in 5-10 passages were randomly allocated into three treated groups. Cells were cultured either in Dulbecco's modified Eagle's medium (DMEM) + 10% foetal bovine serum (FBS) until 90% confluent (group 1, confluent), in DMEM + 10% FBS + 30 microM roscovitine for 12 h (group 2, roscovitine), or in DMEM + 0.5% FBS for 5 days (group 3, serum starvation). Most of the cells (>80%) in all groups were arrested at the G0/G1 stage. Although the rates did not differ, cells in group 1 showed an increased cell population arrested at the G0/G1 phase. Significantly (p < 0.05) higher rates of apoptosis occurred in group 3 than in group 1 and 2 (10% vs 6% and 6%, respectively). No differences in chromosomal abnormality were observed among groups. However, by increasing the number of cell culture passages up to 15, significantly (p < 0.05) higher chromosomal abnormality was observed than in 5 and 10 passages (39% vs 28% and 23%, respectively) in group 1. The results clearly indicated that bovine foetal fibroblasts could be effectively synchronized at G0/G1 stages by all the three different treatments, confluent, roscovitine and serum starvation. However, cells in confluent showed reduced apoptosis and necrosis when they underwent 5-10 passages, exhibiting increased percentage of cells with stable chromosome diversity. Hence, cells in confluent merit further studies before they could be used as nuclear donors. 相似文献
3.
Transformation of the nitrogen cycle: recent trends, questions, and potential solutions 总被引:12,自引:0,他引:12
Galloway JN Townsend AR Erisman JW Bekunda M Cai Z Freney JR Martinelli LA Seitzinger SP Sutton MA 《Science (New York, N.Y.)》2008,320(5878):889-892
Humans continue to transform the global nitrogen cycle at a record pace, reflecting an increased combustion of fossil fuels, growing demand for nitrogen in agriculture and industry, and pervasive inefficiencies in its use. Much anthropogenic nitrogen is lost to air, water, and land to cause a cascade of environmental and human health problems. Simultaneously, food production in some parts of the world is nitrogen-deficient, highlighting inequities in the distribution of nitrogen-containing fertilizers. Optimizing the need for a key human resource while minimizing its negative consequences requires an integrated interdisciplinary approach and the development of strategies to decrease nitrogen-containing waste. 相似文献
4.
Felix S. Mwangala Leonard P. Sarna Terry D. Galloway G. R. Barrie Webster 《Pest management science》1993,39(3):179-184
Fenvalerate and permethrin residues on hair of groups of cattle that received either two tags per adult animal or one tag for every other adult animal were determined using gas chromatography over a three-month period in 1987 and 1988. Cattle with two tags had consistently higher residues than cattle with one tag. This difference was statistically significant (P < 0.05) in the first month for residues on the head and in the first two weeks for residues from the body in 1987. Residues on cattle with one tag and without a tag in the same herd were similar (P > 0.05) on each sampling day on all regions. Residues on the hair from the head of cattle with two tags were greater than on the body and rump (P < 0.05) during the first 28 days. Residues found on hair on days 14 and 84 following tag application declined by 80–86% on the head, 73–78% on the body, and 36–86% on the rump. Isomeric compositions of fenvalerate (range 51–61% SR, RS: 39–49% SS, RR) and permethrin (range 61–67% trans: 33–39% cis) were consistent during the study. Rainfall reduced residues on hair. 相似文献
5.
Bartels KE Higbee RG Bahr RJ Galloway DS Healey TS Arnold C 《Journal of the American Veterinary Medical Association》2003,222(12):1733-1739
OBJECTIVE: To determine outcome of and complications associated with prophylactic percutaneous laser disk ablation in dogs with thoracolumbar disk disease. DESIGN: Retrospective study. ANIMALS: 277 dogs. PROCEDURE: Medical records of dogs with a history of thoracolumbar disk disease in which the 7 intervertebral disks from T10-11 through L3-4 were ablated with a holmium-yttrium-aluminum-garnet laser inserted through percutaneously placed needles were reviewed. Complications and episodes of a recurrence of neurologic signs (eg, paresis or paralysis) were recorded. Owners were contacted by telephone for follow-up information. RESULTS: Nine of 262 (3.4%) dogs for which follow-up information was available had a recurrence of paresis or paralysis. Follow-up time ranged from 1 to 85 months (mean, 15 months); signs recurred between 3 and 52 months (mean, 15.1 months) after laser disk ablation. Acute complications occurred in 5 dogs and included mild pneumothorax in 1 dog, an abscess at a needle insertion site in 1 dog, and proprioceptive deficits in 3 dogs, 1 of which required hemilaminectomy within 1 week because of progression and severity of neurologic signs. One dog developed diskospondylitis. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that prophylactic percutaneous laser disk ablation is associated with few complications and may reduce the risk of recurrence of signs of intervertebral disk disease in dogs. 相似文献
6.
P. E. J. Galloway F. J. Barr P. E. Holt P. J. Brown T. J. Gruffydd-Jones 《The Journal of small animal practice》1997,38(5):220-224
A cystic thymoma was identified in an eight-year-old domestic longhair cat with a chronic cough. Radiographs indicated a large mass of soft tissue density in the anterior thorax. Ultrasonography revealed an echogenic mass occupying the cranial and mid-thorax with a slight swirling movement of the echoes. Subsequent drainage under ultrasound guidance yielded a cholesterol-rich fluid. The mass was resected at exploratory thoracotomy and the diagnosis of thymoma confirmed. There was no sign of recurrence one year postoperatively. The clinical features and unusual laboratory findings are presented and compared with previously reported cases of thymomata in the cat. 相似文献
7.
RT NORRIS CL McDONALD RB RICHARDS MW HYDER SP GITTINS GJ NORMAN 《Australian veterinary journal》1990,67(7):244-247
In the first of 2 experiments, a simulated voyage was conducted to examine the effects of various treatments on bodyweight change and feeding frequency of inappetant sheep at the end of lot-feeding (non-feeders). The treatments, applied during simulated shipping, were: normal quantities of feed and length of troughs; extra trough length; extra feed. Adult Merino wethers (n = 108) were used in each treatment. A voyage to the Middle East was then conducted to establish whether shipboard mortality could be reduced by separating non-feeders (n = 305) from feeders (n = 5,620) late in the feedlot hase and housing the groups separately aboard ship. A control group of non-feeders (n = 215) mixed with feeders (n = 5,732) was used for comparison. Bars (marker bars), containing a coloured dye, were attached to feed troughs to mark sheep that fed. Most non-feeders (82%) began eating when placed in shipping pens in both studies. However, there was no significant difference in percentage of sheep that fed between non-feeders given extra trough length or extra feed compared with non-feeders given standard management at any stage of simulated shipping. There was no significant difference in mean bodyweights between treatment groups on days 1, 8 and 15 of simulated shipping. Differences in bodyweight on d 22 were probably associated with different levels of gut fill. Death rates were not significantly different in separated and control groups (1.1%, 0.9%, P = 0.6) in the voyage of 14 d to the Middle East.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
9.
Monensin controlled-release intraruminal capsule for control of bloat in pastured dairy cows 总被引:1,自引:0,他引:1
LB LOWE GJ BALL VR CARRUTHERS† RC DOBOS‡ GA LYNCH PJ MOATE PR POOLE† SC VALENTINE 《Australian veterinary journal》1991,68(1):17-20
Monensin, a polyether ionophore antibiotic, is potentially an important agent for bloat relief in dairy cows grazing temperate legume-based pasture. A series of studies was undertaken to determine the effect of monensin, when delivered continuously in the rumen of lactating dairy cows by means of controlled-release capsules (monensin CRC). Such devices release approximately 300 mg/head/day for 100 d. A short-term pilot study made at Ruakura, New Zealand, tested monensin CRC in cows selected for high susceptibility to bloat and grazing lucerne (Medicago sativa) or red clover (Trifolium pratense). Treatment significantly reduced the incidence of bloat, while milk yield and protein yield were increased. There was no effect on fat yield. Following the pilot study, 6 large-scale field experiments involving a total of 368 lactating dairy cows, were made in Australia and New Zealand to confirm the effectiveness of monensin CRC for bloat control and to measure the effect of such treatment on milk production and composition. A severe bloat problem occurred in 2 experiments, mild bloat occurred in 2 others, while no visual signs of bloat were observed in the remaining 2 experiments. Bloat was significantly (P less than 0.05) reduced by monensin CRC treatment when data was pooled over the 4 experiments in which bloat occurred. Daily milk yield was increased in all experiments from a mean of 17.7 in untreated groups to 18.8 kg/head/day (P less than 0.05) in monensin CRC-treated cows. Protein percentage was not affected by treatment, while there was a decrease from 4.29 to 4.10% fat, although total fat yield was not affected.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.