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1.
撒坝猪乳头数遗传力及其与繁殖性能关系的研究   总被引:4,自引:0,他引:4  
本研究对 4个世代共 577头撒坝猪的乳头数进行了分析 ,并用HARVEY程序对乳头数的遗传力进行了估计 ,同时利用 1 2 8头有繁殖性能记录的母猪资料对乳头数与繁殖性状的关系进行了分析。结果表明 ,各世代的乳头数存在着显著差异 ,且逐代均有显著提高 ;乳头数的遗传力为 0 .331 ;乳头数与总产仔数和活产仔数间遗传相关和表型相关均为负值 ,与初生窝重、2 0日窝重、断奶仔数和断奶窝重间则存在着正的遗传相关和表型相关 ;乳头数与所有繁殖性状的环境相关都较弱 ( -0 .0 0 2~ 0 .0 94 )  相似文献   

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主要研究仔猪出生顺序、出生重、性别等因素对乳头序列确定以及一周龄仔猪增重的影响。试验发现仔猪乳头序列的固定时间在不同窝之间存在很大差异,乳头固定受诸多因素的影响。固定过程中仔猪可能会改变偏好乳头,仔猪越频繁的更换乳头就越难固定乳头。出生重较大的仔猪初次确定偏好乳头的时间和乳头序列最终固定的时间都较短,并且增重明显较多。出生顺序、性别对乳头序列影响不显著,对仔猪增重的影响也不明显。  相似文献   

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Onchocerca armillata was found in 3838 (95.4%) and Elaeophora poeli in 70 (1.7%) out of 4025 samples of aortas collected from cattle slaughtered at Tabora in Tanzania during the calendar year 1988. Gross lesions of the affected aortas varied from mild to severe, characterised by parasitic tunnels, nodules and corrugated calcified ridges on the aortic wall. Histological sections revealed changes as a result of tissue reaction against the parasites which were embedded into the intima of affected aortas. Calcification and hyaline degeneration were common features. The high prevalence of O. armillata and the extensive pathological lesions observed would seem to warrant assessment of the importance of onchocercosis in animal production in the tropics. Meanwhile, further studies are required to elucidate the epizootiology of aortic onchocercosis and elaeophorosis in order to devise practicable diagnosis, treatment and control methods.  相似文献   

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: Public concerns over the widespread prophylactic use of antibiotics have led to a search for alternatives to dry cow therapy for the prevention of intramammary infections. A popular alternative is to infuse a teat seal at drying-off. The teat seal is a viscous non-antibiotic formulation and when it is infused into the teat canal and the teat sinus it forms an internal seal that provides a physical barrier to invasion by mastitis-causing pathogens. Enhancement of teat seal formulations may be achieved using non-antibiotic additives such as bacteriocins, potent proteins produced by some bacteria that have the ability to kill other microorganisms. This paper traces the history of investigations at Moorepark Research Centre into the efficacy of teat seal plus lacticin 3147, a bacteriocin produced by Lactococcus lactis DPC3147, in the prevention of intramammary infections in dry cows. Indications from on-going investigations are that a dry cow formulation combining the two products has considerable potential as a non-antibiotic prophylactic product.  相似文献   

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奶牛在产奶阶段发生较多的疾病主要为乳房炎,从而影响产奶量,奶牛一旦患上乳房炎,会导致奶牛生长发育缓慢,经济效益也会受到很大的影响.笔者在多年的临床上,应用黄芪对奶牛乳房炎进行防治,取得了显著治疗效果.本文重点对黄芪中药制剂在奶牛乳房炎防治中的生理功能和预防奶牛乳房炎的作用机理进行阐述,以供同行参考.  相似文献   

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Teat and udder suspensory scores from 9,418 first-parity Gelbvieh cows and growth records from 19,119 calves were used to estimate genetic and environmental parameters for teat and suspensory score and to investigate the relationship of teat and suspensory score with calf growth traits and maternal genetic growth effects. First-parity cows did not have multiple records within 280 d, gave birth to one calf, were 4 yr of age or younger at first-calving, and were at least 50% Gelbvieh. Producers scored cows within 24 h of parturition. Teat score (T), a subjective measure of teat size, ranged from 0 (very large) to 50 (very small), and suspensory score (S), a subjective score of udder support, ranged from 0 (very pendulous) to 50 (very tight). Unadjusted birth weight (BW), weaning weight, and yearling weight of the calves, born in the first three parities to cows with first-parity T and S records, were used to calculate pre- and postweaning ADG (WG and YG, respectively). A mixed model was used for the multiple trait analysis of T, S, BW, WG, and YG, which included herd-year, month of calving, age of cow at calving, and sex of calf (included only for BW, WG, and YG) as systematic effects; regression on the percentage of Gelbvieh; and additive animal and maternal genetic of dam (included only for BW and WG), maternal permanent environment (included only for BW and WG), and residual as random effects. The genetic correlation between T and S was 0.95, suggesting that T and S are basically the same trait in this dataset. The genetic correlations between T (S) with direct BW, WG, and YG and with maternal BW and WG were -0.18 (-0.06), 0.38 (0.31), 0.09 (-0.01), -0.16 (-0.16), and -0.47 (-0.55), respectively, suggesting that cows with smaller teats and tighter udders produced less milk and raised calves that had higher genetic growth potential for WG. Further, the Pearson correlations between predicted breeding values of T and S with maternal WG indicated that animals with extremely large teats or pendulous udders may produce more milk, but that the calf may have trouble accessing it. Conversely, with extremely small teats or tight udders, smaller amounts of milk would be produced and there may be a problem producing enough milk to maintain the growing calfs maintenance requirements. Therefore, it may be more beneficial for producers to select animals that have intermediate breeding values for T and S.  相似文献   

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Lameness is a multifactorial condition influenced by the environment, genetics, management and nutrition. Detection of lameness is subjective and currently limited to visual locomotion observations which lack reliability and sensitivity. The objective of this study was to search for potential biomarkers of inflammatory foot lesions that underlie most cases of lameness in dairy cows, with a focus on the sickness response and relevant endocrine, immune and behavioral changes. Serum and peripheral blood mononuclear cells (PBMC) were collected from eight sound and eight lame high-producing Holstein cows. Immune cell activation was investigated in PBMCs using a candidate gene approach in which the expression of pro-opiomelanocortin, interleukin-1beta, l-selectin, matrix metalloproteinase-9 and glucocorticoid receptor-alpha was measured via quantitative real time-RT-PCR. Endocrine changes were investigated by monitoring serum concentrations of cortisol and dehydroepiandrosterone (DHEA). Additionally, systematic behavioral observations were carried out to characterize a behavioral profile associated with a sickness response typical of this condition. Lame cows showed significantly lower eating (P=0.01) and ruminating (P=0.01) behaviors and higher incidence of self-grooming (P=0.04) compared to sound cows. Lame cows also showed a 23% decrease in serum DHEA (P=0.01) and 65% higher cortisol:DHEA ratio (P=0.06) compared to sound cows. However, no significant differences were found in candidate gene expression between lame and sound cows. In association with sickness behaviors, serum DHEA concentration and cortisol:DHEA ratio are promising objective indicators of inflammatory foot lesions in dairy cattle and may be useful as diagnostic targets for animals in need of treatment.  相似文献   

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奶牛子宫复旧的B-超影像学研究   总被引:2,自引:1,他引:2  
应用连续直肠检查法和B型实时超声断层扫描仪(B- 超)监测法,对38 头中国荷斯坦奶牛的子宫复旧过程和复旧规律进行研究。实验结果表明:经连续直肠检查法监测,受试牛子宫孕角、空角和子宫颈复旧的平均时间分别为(37.4±31) 、(314±49)和(36.8 ±49) d;用B- 超监测则为(35.5 ±4.5)、(30.8 ±5.9) 和(37 .5 ±5.0) d。并且B-超监测还发现,分娩当天子宫肌层平均厚度为1.65 cm ,产后第23 天时减少到1.35 cm ;产后第5 天在超声影像上可见子宫内膜,平均厚度为0.3cm ,第15 天为0 .6cm ,而到产后23 d 平均增厚到1.02cm ,子宫复旧完成时,子宫壁平均厚度为1.0 cm ;两子宫角的横切面轮廓清晰,大小基本相同,超声影像变白。  相似文献   

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The relationship between vaginal discharge, site of inflammation in the reproductive tract and species of bacteria isolated was examined in cows that were either normal, subfertile, or had had an abnormal parturition. Microbiological and cytological examinations were performed on uterine swabs from 221 cows and cervical swabs from 107 cows. There were 167 subferitle cows, 144 of which had failed to conceive to 3 or more services (FTC) and 23 of which had not had a visible oestrus since calving (NVO). Metritis was diagnosed in 22% of the FTC cows, 48% of the NVO cows, and 12% of the cows with abnormal parturition. Fifty percent of cows with metritis had purulent vaginal discharge. However, only 25% of a total of 91 cows with vaginal discharge had metritis; the remainder had cervicitis. Fifty-four percent of subfertile cows had cervicitis without metritis. Mixed infection with aerobes and anaerobes was significantly correlated with uterine inflammation and was found in 20% of cows with metritis. The rate of isolation of H.somnus from inflamed uteruses (22%) and inflamed cervixes (39%) was significantly greater than the isolation rate from normal uteruses (8%) and cervixes (10%). No bacteria were isolated from 50% of inflamed uteruses and 37% of inflamed cervixes. The number of subfertile cows with or without metritis that subsequently conceived was not significantly different.  相似文献   

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To evaluate the ultrasound technique as a method for estimating the effect of mechanical milking on teat thickness in Murciano-Granadina goats, the following work was carried out with a twofold objective: (1) to study the most suitable ultrasound exploration frequency for this breed and the effect of the operator in applying the technique and (2) to validate the approach, comparing it with measurements taken by another estimation method (cutimeter) and performing ultrasound examinations in cows using the same methodology. To this end, three studies were designed. In the first study, 2 experiments were carried out: (a) the first (E1) tested the frequencies 5, 7.5 and 10 MHz; (b) the second (E2) tested the frequencies 3.5 and 5 MHz. In the second study, 2 different independent operators (OP) performed sonography on the same animals (E3), chose the best image of ultrasound examinations recorded as a video sequence (E4) and carried out measurements on ultrasound images (E5). In the third study, the technique tested in goats was applied in 10 Holstein cows (E6) and, finally, ultrasound scans were performed at 5 MHz frequency and cutimeter measurements taken in 63 goats (E7).  相似文献   

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We evaluated age-related changes in serum osteocalcin concentrations in non-periparturient cows and variations in serum osteocalcin concentration in periparturient primiparous and multiparous cows. The serum osteocalcin levels were evaluated in 144 non-periparturient Holstein dairy cows aged 11 days to 10 years; these levels were the highest in the youngest cows, appeared to steadily decrease with age until the time of the first calving, and were subsequently maintained at low levels. Between 14 days before calving and 21 days after calving, the serum osteocalcin levels were significantly higher in the primiparous cows than in the multiparous cows. A comparison between age-matched non-periparturient and periparturient cows showed that serum osteocalcin levels were significantly lowered during late gestation in both primiparous and multiparous cows. These results suggest that serum osteocalcin measurement might be useful for the detection of mineral imbalances at the time of parturition in cows.  相似文献   

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应用B型实时超声断层扫描仪(B- 超),对奶牛子宫复旧过程进行研究。对38 头中国荷斯坦奶牛,用B- 超和连续检查法监测了子宫复旧过程。结果,经连续直肠检查法监测,受试牛子宫孕角、空角和子宫颈复旧的平均时间分别为(37 .4±3.1)、(31.4 ±4.9)和(36.8 ±4.9) d;用B- 超监测则为(35 .5±4.5) 、(30.8 ±5.9)和(37.5 ±5.0)d。并且B-超监测还发现,分娩当天子宫肌层平均厚度为1.65 cm ,产后23 d 时减少到1.35cm ;产后第5 天在超声影像上可见子宫内膜,平均厚度为0 .3 cm ,第15 天为0 .6 cm ,而到产后23 d 平均增厚到1.02 cm ,子宫复旧完成时,子宫壁平均厚度为1 .0 cm ;两子宫角的横切面轮廓清晰,大小基本相同,超声影像变白。研究表明B- 超监测奶牛子宫复旧过程是可行的。  相似文献   

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The objective of this research was to determine changes in IGF-I levels in serum and follicular fluid, and immunoreactivity of the follicle wall of cows with spontaneous (slaughter specimens) or ACTH-induced follicular cysts, and to compare results to normal cycling (control) cows after selection of the ovulatory follicle. Concentrations of IGF-I in serum did not differ between control and cystic animals (p=0.76). Fluid from the ovulatory follicle in control cows had 41% higher concentrations of IGF-I than that from cystic follicles collected at slaughter (spontaneous cysts; p<0.05) and 70% higher than that in induced follicular cysts (p<0.05). An intense positive immunostaining with anti-IGF-I was observed in granulosa cells (p<0.05) and in the theca interna (p<0.05) of secondary and tertiary follicles in all three groups of animals, but staining was less intense in cystic (p<0.05) and atretic follicles (p<0.05). This study provides evidence to suggest that cystic ovarian disease in cattle is associated with decreased concentrations of IGF-I in follicular fluid, but not in serum, and decreased production of IGF-I in the follicular wall. These data support the notion that IGF-I plays a role in the regulation of folliculogenesis, and may participate in the pathogenesis of cystic ovarian disease in cattle.  相似文献   

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This review deals with the features of clinical and subclinical laminitis in cattle. Prominent clinical signs of acute laminitis are a tender gait and arched back. The sole horn reveals red and yellowish discolourations within five days. In subacute and chronic cases clinical signs are less severe. In chronic laminitis the shape of the claws is altered. Laminitis is frequently followed by sole ulceration and white zone lesions. Blood tests showed no significant changes for laminitic animals. Arteriographic studies of claws affected by laminitis indicated that blood vessels had narrowed lumens. Gross pathology revealed congestion of the corium and rotation of the distal phalanx. Histopathologic studies indicate that laminitis is associated with changes of the vasculature. Peripartum management and nutrition are important factors in its aetiology. It is hypothesised that laminitis is evoked by disturbed digital circulation. In the pathogenesis of acute laminitis three factors are considered important: the occurrence of thrombosis, haemodynamic aspects of the corium, and endotoxins which trigger these pathologic events.  相似文献   

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随着我国乳牛业奶产量的不断提高,奶牛对营养需求量的增加,高产奶牛的物质代谢旺盛以及各器官系统的负荷沉重;随着生态环境因素对奶牛个体的影响日益加重,奶牛内科病的种类、类型、分布也发生了很大的变化。在临床上,奶牛的营养代谢病、中毒病、微量元素性疾病、生物地质化学病、环境污染病、应激以及免疫缺陷疾病等不断增多。在奶牛内科病的历史上很少见过或不曾见过的疾病类型或“综合征”出现了,并呈现出内科病理的多样性(Medicine pathology diversity)。  相似文献   

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