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Precision Agriculture - Soil acidification is a growing problem in semi-arid agroecosystems. In the state of Montana, USA, soil pH levels below 5.5 have been documented in nearly half of the... 相似文献
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ACE inhibition in goats under fixed‐time artificial insemination protocol increases the pregnancy rate and twin births 下载免费PDF全文
VP Fernandes Neto MNN Silva AS Costa D Kunkel AS Júnior LCS Feitosa MCS Muratori APR Costa 《Reproduction in domestic animals》2018,53(4):1006-1008
To assess the effect of the angiotensin‐converting enzyme (ACE) inhibition on the efficiency of the fixed‐time artificial insemination (TAI), 69 goats were divided randomly into two groups: enalapril (n = 35) and control (n = 34). In the experiment, all animals underwent the protocol of fixed‐time artificial insemination for 12 days. Enalapril group received enalapril maleate dissolved in saline (Enalapril, Lab Teuto Ltda) subcutaneously at the following doses: 0.2 mg/kg/day in D0‐D2; 0.3 mg/kg/day in D3‐D6 and 0.4 mg/kg/day in D7‐D11. The control group received the corresponding volume of 0.9% saline solution. We performed a single insemination 36 hr after sponge removal using frozen semen from two adult male goats with recognized fertility. The ultrasound pregnancy diagnosis was 30 days after the artificial insemination (AI). There was significant increase in pregnancy rates and twinning as well as a decrease in foetal loss in animals receiving enalapril (p < .01). The use of ACE inhibitors during the TAI protocol was shown to be a promising alternative to increase the efficiency of such reproductive biotechnology. 相似文献
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Bayemi P. H. Leinyuy I. Nsongka V. M. Webb E. C. Ebangi A. L. 《Tropical animal health and production》2010,42(8):1779-1783
A study was carried out to evaluate the viability of extended cattle semen, without freezing, under different storage conditions.
The semen was collected from Holstein Friesian bulls using artificial vaginas. The semen was extended and stored in a 3-by-4
factorial design (storage system × ice change). The storage media were ice boxes, buckets, and refrigerator. The ice in these
media was either replaced daily, on the first and third day, first day only, or no ice at all after the semen collection.
Results showed an overwhelming evidence of the effect of storage medium and ice change on sperm viability (P < 0.0001). Individual motility before processing was highest in the refrigerator with averages of 44.5%, 39.5% in ice boxes,
and 10% in buckets during the 8-day experiment. There was no significant difference (P > 0.05) in progressive motility after processing in the refrigerator (34%) and in ice boxes (33%) but significantly higher
(P < 0.01) to the 10% obtained in buckets. It was shown that spermatozoa in the ice box retained 45% individual motility up
to the sixth day after semen was collected on the condition that the ice was changed on the third day. Progressive motility
after processing in the ice box was 40% up to the sixth day with the ice changed on the third day while the spermatozoa were
well preserved up to the fourth day in the same medium if the ice put on the first day was not changed. This study shows that,
if farmers plan to inseminate cows within the first day after semen collection, they can use buckets with ice for the transportation
of the extended semen ampoules from the artificial insemination center. Otherwise, the semen needs to be kept in ice boxes
and the ice changed on the third day after collection and this semen could be used within a week. 相似文献
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施用不同土壤改良剂对砖红壤酸度的影响 总被引:7,自引:2,他引:5
对砖红壤施用不同的改良剂,经一年的大田试验,测定土壤的活性酸与交换酸研究不同土壤改良剂对酸性土壤酸度的影响。试验结果表明:滤泥单施与石灰单施处理能有效降低土壤的活性酸以及交换性酸的含量,有较好的降低土壤酸度的效果,而施用绿肥、甘蔗渣、羊粪以及羊粪与膨润土混施均不能有效降低土壤的酸度。 相似文献
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The various isotope effects on the superconducting transition temperature of Mo(2)B and W(2)B have been measured. Together with resistivity data they indicate that the d-shell forms a highly stable electron configuration for molybdenum and tungsten. This leads to an understanding of high superconducting transition temperatures. 相似文献