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101.
102.
Hibret A Toé F Mukasa-Mugerwa E Kassa T Markos T 《Tropical animal health and production》2001,33(3):219-227
Clinical examination, bodily condition score (BCS), heart girth (HG), body length (BL), wither height (WH), and scrotal circumference (SC) were assessed on 486 mature Ethiopian Menz rams, on small farms, in local markets, and at the main abattoir in Addis Ababa from December 1994 to April 1995. Almost 27% of the rams were found to be unfit for breeding. Poor general condition, mainly in the form of respiratory disorders, was seen in 1.2% of the rams. Balanoposthitis, epididymitis and orchitis were the most common pathological conditions, affecting the external reproductive organs in 14.6%, 4.5% and 4.1% of the rams, respectively. Testicular calcification, cysts and testicular haemorrhagic lesions were detected in 4, 6 and 8, respectively, of the 60 rams examined at necropsy. The BCS, HG, BL and WH averaged 2.1±0.5, 67.7±5.0 cm, 60.1±4.5 cm and 60.1±4.3 cm, respectively. The mean SC was 25.5±3.9 cm and did not vary significantly with age (p>0.05). Among the linear body measurements, the highest correlation was between BL and WH (r = 0.66). SC was found to be most closely correlated to HG (r = 0.46). More investigations into the relationship between the present findings and actual fertility, and on their practical application in the selection of rams for breeding is recommended. 相似文献
103.
肉用西门塔尔牛改良云南黄牛的效果初报 总被引:2,自引:0,他引:2
对云南黄牛、西门塔尔与云南黄牛的杂交牛(西本杂)体尺体重进行了测定,结果西本牛与本地牛体尺体重都有了显著提高(P<0.01)。西本杂牛的初生、6、12、18、24月龄体重比同龄本地牛分别高出82%、18%、69%、50%、78%。 相似文献
104.
流动沙丘表面输沙率的理论计算方程 总被引:5,自引:1,他引:5
本文研究流动沙丘表面上输沙率的理论计算,得出输沙率是风速的二次函数且与沙丘表面沙粒平均粒度的1.43次方成反比的新结论。 相似文献
105.
短季棉生育进程、皮棉产量与积温、光照的关系 总被引:5,自引:0,他引:5
以中棉所16号为试验材料,经三年试验,研究短季棉在不同年际间气温、光照条件的差异及对生育进程和皮棉产量的影响。结果表明,同一品种不同年际间气温不同,各生育阶段和全生育期的长短差别很大,但所需积温基本一致。生育进程的快慢主要取决于积温,光照无明显的直接影响。同为富光照年,高温年比低温年产量高。在适宜范围内提高温度,对促进光合作用,增加皮棉产量有一定影响,尤其能提早成熟。根据品种对积温的需求,结合当地的气候条件,科学调控棉花的开花结铃期,是实现短季棉高产、稳产、早熟的有效途径。 相似文献
106.
The study was designed to determine differences between normal mares and mares with endometrial pathology in the inflammatory response after bacterial challenge. Six normal mares (biopsy category I) and 4 mares with pathological endometrial changes (biopsy category II) were given an intrauterine infusion of β-hemolytic streptococci on the second day of estrus. All mares had a similar kind of inflammatory response after the bacterial inoculation as assessed by rectal and vaginal examinations. There were no significant differences in the amount of discharge, uterine tone, uterine size and cervical relaxation between the groups. Leukocytic response, as determined by endometrial smears and biopsies, was of the same magnitude in both groups. Two mares from the pathological group were not able to eliminate the infection, but had vaginal discharge and bacteriologically positive uterine swabs until the end of the experiment. It is concluded that the inability of some mares to clear uterine infections cannot be explained by a deficient inflammatory response. 相似文献
107.
The relationship between some skin characteristics and hemoglobin values during the growth period were statistically examined in standard male minks. Significant correlations) (P < 0.05–0.001) were found between the hemoglobin concentrations determined at 3 points during the growth period (in July, August and November) and the density and colour of underfur, and skin length, respectively. According to the study even the early hemoglobin values in July and August have a significant influence on the size and quality of the pelt. Mink kits with low hemoglobin values are liable to develop a winter fur coat with defective pigmentation and hair structure of the underfur. Anemic minks develop the most extreme stage of the pigmentation defect and these so-called cotton fur skins have little value in the fur garment industry. When these abnormal hemoglobin values are recognized at an early stage, cotton fur skins may be avoided, and larger skins of better quality may be produced. 相似文献
108.
109.
通过对5头体细胞克隆母犊牛及其同期自然繁殖出生的荷斯坦母犊牛初生期、6月龄、12月龄的体重、体尺指标测定,初步分析了其生长发育速度的变化规律。结果表明:(1)克隆牛初生重53.67±7.00kg,明显高于自繁奶牛(P<0.01),6月龄体重141.00±16.49kg,明显低于自繁奶牛(P<0.01),12月龄体重302.80±32.17kg,与自繁奶牛基本相当;(2)克隆牛0~6月龄期间平均日增重0.70±0.11kg明显低于自繁奶牛(P<0.01),6~12月龄期间平均日增重0.90±0.12kg,与自繁奶牛基本相当(P>0.05),0~12月龄期间平均日增重0.70±0.11kg,与自繁奶牛基本相当(P>0.05);(3)克隆牛初生体尺指标明显大于自繁奶牛(P<0.01),6月龄体尺指标明显小于自繁奶牛(P<0.01),12月龄体尺指标与自繁奶牛相当(P>0.05);(4)克隆牛0~6月龄期间体尺平均增长明显低于自繁奶牛(P<0.01),6~12月龄期间体尺平均增长明显高于自繁奶牛(P<0.01),0~12月龄期间体尺平均增长明显低于自繁奶牛(P<0.01)。 相似文献
110.
Gengmei?Xing Jun?Zhang Jing?Liu Xiaoyan?Zhang Genxuan?WangEmail author Yafu?Wang 《Phytoparasitica》2003,31(5):499-514
The impacts of elevated CO2 and soil water on the population dynamics, adult fecundity and nymphal period of the bird cherry-oat aphidRhopalsiphum padi (Linnaeus) were evaluated in three experiments: (i)Combined effects of CO
2
and soil water on aphid populations. Spring wheat was grown in pots at three CO2 concentrations (350, 550 and 700 ppm) and three soil water levels (40%, 60% and 80% of field water capacity, FWC) in field
open-top chambers (OTC) and infested with the bird cherry-oat aphid. Aphid population dynamics were recorded throughout the
growing season; at the same time, adult fecundity and duration of the nymphal period were recorded. Chemical composition of
spring wheat leaves was also analyzed. (ii)Indirect effects of CO
2
concentrations and soil water on aphid adult fecundity and nymphal period. The experiment was conducted with the leaf discs method in the laboratory. Aphids were reared on leaf discs excised from
the treated wheat in OTC with different CO2 and soil water levels. (iii)Direct effects of CO
2
concentrations on aphid adult fecundity and nymphal period. Aphids were reared on leaf discs excised from the wheat grown under natural conditions. The experiment was conducted with
the leaf disc method in OTC with the three CO2 concentrations. It was found that the direct effect of CO2 concentration on aphid population parameters was minor. CO2 and soil water affected aphid population indirectly through their effects on wheat characteristics. The aphid population
under 550 ppm CO2 was far larger than the one under 350 ppm CO2, whereas the population under 700 ppm CO2 was slightly higher than that under 550 ppm CO2. The largest aphid population was obtained with the 60% soil water treatment, regardless of CO2 treatment. The effects of CO2 concentration on aphid population were, however, not significantly correlated with soil water level. Adult fecundity increased
with CO2 concentration, the highest fecundity being achieved under 60% FWC treatments. The nymphal period was not affected by CO2 concentration. The shortest period occurred under 60% FWC. Atmospheric CO2 and soil water had significant effects on the chemical composition of the wheat leaves. Aphid population size was positively
correlated with leaf water content, concentrations of soluble proteins, soluble carbohydrates and starch, and negatively correlated
with DIMBOA and tannins concentrations.
http://www.phytoparasitica.org posting Oct. 20, 2003. 相似文献