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Insulin-like growth factor binding protein-2 (IGFBP2) is a key regulator of IGF activity that has been associated with insulin resistance and obesity. In cows, IGFBP2 mRNA expression is differentially regulated according to nutritional status in different tissues including the liver, reproductive tract, and mammary gland. This study investigated associations between single nucleotide polymorphisms (SNPs) in bovine IGFBP2 with fertility, milk production, and metabolic traits in Holstein-Friesian dairy cows. Fertility was assessed in heifers by measuring age at first service, age at first conception, and age at first calving. During the first and second lactation, the number of postpartum days for commencement of luteal activity (based on milk progesterone profiles), days to first service, days to conception, average milk production per day, 305-day milk yield, total milk yield, and total days in milk were recorded. Blood samples were taken at -1, +1, and +8 weeks relative to first and second calving for assessment of metabolic status (IGF1, insulin, beta-hydroxybutyrate, and glucose). Five novel SNPs were identified in IGFBP2, two of which had significant associations with fertility (age at conception in heifers and commencement of luteal activity) and 305-day milk yield in lactation 1. Trends of association were also observed with the peripartum metabolic status, in particular the glucose, insulin, and beta-hydroxybutyrate concentrations around second calving. These results indicate that IGFBP2 SNPs may influence tissue mobilization in dairy cows and may thus be of interest for marker assisted selection.  相似文献   

3.
At Days 26 to 58 after AI, 138 Holstein-Friesian dairy cows were repeatedly examined by ultrasonography, using a 7.5 MHz linear-array rectal transducer. The total calving rate was 37.6% (52/138), and late embryonic mortality occurred 8.6% of the cows (12/138). On the days of ultrasound scanning, blood samples were drawn from the jugular vein for measuring the concentration of bovine pregnancy-specific protein B (bPSPB) and bovine pregnancy-associated glycoprotein 1 (bPAG 1). When compared with calving results, there were no significant differences in accurate diagnosis of pregnant cows were found between the 3 methods. However, when recognition of an embryo proper with a beating heart was used as the criterion for positive ultrasonographic diagnosis significantly fewer (P < 0.001) pregnant cows were correctly identified than by the other 2 tests. When compared with the noncalving cows, significantly fewer (P < 0.001) false positive diagnoses were made by the 2 ultrasonographic tests than by the PSPB and bPAG 1 tests, while significantly fewer (P < 0.001) false positive diagnoses were made by the bPSPB test than by the bPAG 1 test. The accuracy of detecting nonpregnant animals by both protein tests was limited by the relatively long half-life of these proteins after calving and by early embryonic mortality.  相似文献   

4.
Polymorphisms of the prolactin (bPRL) and growth hormone (bGH) genes were studied comparatively in the Russian and German Black-and-White and Yaroslavl cattle breeds. Two polymorphisms were studied for each gene. In the case of the bPRL gene, the polymorphism of the 5'-untranslated region was examined by microsatellite analysis and the RsaI polymorphism of exon 3, by RFLP analysis. In the case of the bGH gene, the MspI polymorphism of intron III and the AluI polymorphism of exon 5 were assessed by RFLP analysis. Differences in allele and genotype frequencies were observed both between and within breeds. The heterozygosity at the RsaI marker was low (9.4%) in the Russian Black-and-White breed; that at the microsatellite of the bPRL gene was low (3.2-24%) in all breeds examined. Homozygotes BB at the bPRL gene, which had not been reported earlier for European cattle breeds, were detected in the German Black-and-White and Yaroslavl breeds (at frequencies 0.16 and 0.13, respectively). The frequency of allele MspI(-) of the bGH gene in the Yaroslavl breed was extremely low (0.02), comparable only with that of the Holstein cattle (0.02). The heterozygosity at the AluI polymorphism was higher than at the MspI polymorphism of the bGH gene and reached 55% in the Yaroslavl breed. Genotype BB of the RsaI polymorphism of the bPRL gene tended to show a negative association with the fat content in milk. The genotypes of the AluI polymorphism of the bGH gene were associated with the fat content in milk in the Yaroslavl (F = 4.56, P = 0.013) and German Black-and-White (F = 4.1, P = 0.014) breeds: the highest fat content in milk was observed in the subsample of cows with heterozygous genotype VL.  相似文献   

5.
Relationships among GH genotype (AluI polymorphism), parity, metritis and interval from calving to first ovulation, milk production and body condition score (BCS) loss were determined in dairy cows (n = 307) on four large-scale farms in Hungary. Cows with systemic signs of puerperal metritis or mastitis were excluded. Time of the first postpartum (PP) ovulation was obtained from milk progesterone profiles. Based on GH genotype determination, groups of leucine homozygous cows (n = 246) and valine allele carriers (n = 61) were formed. All animals became cyclic during the study period. The average interval to first ovulation was 27.6 ± 0.69-d PP (mean ± S.D.). Genotype had no effect on the commencement of ovarian cyclicity. First ovulation occurred sooner after calving in pluriparous than in primiparous cows. The greater BCS loss cows had during the first 30-d PP, the longer they took to resume cyclic ovarian function. The interval from calving to first ovulation was substantially affected by farm, but not by mild cases of puerperal metritis. Genotype was not related to cumulative 30-d milk yield or BCS loss after calving. Primiparous cows had lower milk yield than pluriparous ones. Cows with metritis lost more body condition than healthy individuals in the first month postpartum. We concluded that, under field conditions, AluI polymorphism of the bovine GH gene had no effect on the interval from calving to first ovulation and could not be directly related to differences in milk yield and to the extent of BCS loss during the first month after calving in Holstein-Friesian cows.  相似文献   

6.
An on-farm blood progesterone enzymeimmunoassay (EIA) was evaluated as a diagnostic test to predict the time of calving within a 24-hour period in near-term dairy cows. Blood samples were taken daily from 45 cows beginning 5 days prior to their expected due dates until calving, and plasma was stored at -20 degrees C until all cows had calved. The EIA test was performed on frozen-thawed plasma samples, and progesterone concentrations were determined to be low (positive test for calving within 24 hours) or high (negative test for calving within 24 hours). Sensitivity, specificity and predictive value of the EIA to accurately determine parturition within 24 hours were 86.7, 90.8 and 75.0%, respectively. The EIA correctly predicted the day of parturition in 168 of 187 (89.8%) plasma samples. Ten additional cows were similarly monitored except the EIA was performed on whole blood immediately after collection, and the sensitivity, specificity and predictive value of the test were 80.0, 97.6 and 88.9%, respectively. The day of parturition was correctly predicted in 49 of 52 (94.2%) whole blood samples. More than 95% of the cows calved within 24 hours when their plasma progesterone reached < 1.3 ng/ml. When results of the EIA were compared with those of a radioimmunoassay (RIA), the EIA findings were used to correctly classify 190 of 232 (81.9%) plasma samples as having low (< 2.0 ng/ml) or high (>/= 2.0 ng/ml) concentrations of progesterone. The EIA test was found to be a quick, practical means of estimating progesterone concentrations in bovine plasma or whole blood and was a useful test for predicting the day of parturition in cows.  相似文献   

7.
Seven Friesian human lactoferrin (hLf)-transgenic primiparous dairy cows expressing recombinant hLf (rhLf) in their milk were included in the study. After calving, concentrations of rhLf and bovine LF (bLf) in the milk, somatic cell count and milk yield were determined. The concentration of rhLf was found to be constant, about 2.9 mg/mL, throughout the early lactation period of 3 months. The concentration of bLf in colostrum was higher after calving, but decreased rapidly during the first days of lactation. The mean concentration of bLf was 0.15 mg/mL, but concentrations varied between cows from 0.07 mg/mL to 0.26 mg/mL. Based on that, it may be possible to improve the non-specific host defence mechanism in the mammary gland of dairy cows by enhancing the content of rhLf in the milk.  相似文献   

8.
The peripartum period is of critical importance to subsequent health and fertility. Most cows enter a state of negative energy balance (NEB) associated with many metabolic changes which have carry over effects on the resumption and normality of estrous cyclicity and the success of subsequent inseminations. A dataset on 500 lactations explored the relationships between metabolic traits measured before and after calving with fertility. Stepwise multiple regression analysis showed that longer calving to conception intervals were associated with altered profiles of IGF-I, urea and body condition score. These relationships between metabolic profiles and fertility differed between first lactation cows (which are still growing but produce less milk) and mature animals. Early postpartum the liver undergoes extensive biochemical and morphological modifications to adapt to NEB, the uterus is extensively remodeled and must clear bacterial infections, and the ovary must resume ovulatory cycles. RNA isolated from liver and uterine tissues harvested 2 weeks postpartum from cows in mild (MNEB) and severe (SNEB) energy balance was used to screen the Affymetrix 23K bovine microarray. In liver, SNEB resulted in differential expression of key genes involved in lipid catabolism, gluconeogenesis, and the synthesis and stability of IGF-I. This was accompanied by reduced systemic concentrations of IGF-I which is likely to impact on ovarian function and early embryo development. Within endometrium, cows in SNEB showed histological evidence for higher levels of inflammation and the microarray analysis identified groups of differentially expressed genes involved in tissue remodeling and immune response. This may delay uterine repair after calving, likely contributing to the observed reduction in fertility.  相似文献   

9.
Induction of parturition with glucocorticosteroids in cattle is used for research purposes, in diseased or injured pregnant cows, and as a management tool to time parturition. A negative side effect of induction of parturition with glucocorticosteroids is the high incidence of retained placenta that occurs after these calvings. Reaction of the maternal immune system against the ‘foreign’ foetal membranes contributes to the breakdown of the foetal-maternal attachment. Several studies indicate that failure of this immune assisted detachment increases the occurrence of retained placenta. We hypothesized that retained placenta occurring after induction of parturition with glucocorticosteroids is caused by failure of immune assisted detachment of the foetal membranes. The chemotactic activity of cotyledons for mononuclear leukocytes was used as a parameter to see whether immune assisted detachment of the foetal membranes had occurred. Cotyledons were collected from spontaneously calving non-retained placenta cows and from dexamethasone induced non-retained placenta and retained placenta cows. The study showed that the chemotactic activity of cotyledons for mononuclear leukocytes was lower (P < 0.001) in cotyledons obtained from retained placenta cows in which parturition was induced with dexamethasone compared to the chemotactic activity of cotyledons obtained from spontaneously calving non-retained placenta cows, whereas the chemotactic activity of cotyledons obtained from induced non-retained placenta cows was not lower (P = 0.10) than the chemotactic activity of cotyledons obtained from spontaneously calving non-retained placenta cows. We concluded that induction of parturition with dexamethasone causes a failure of immune assisted detachment of the foetal membranes and the accompanying release of chemotactic factors. As a result, the chemotactic activity of cotyledons for mononuclear leukocytes is lower in induced retained placenta cows than in cotyledons from non-retained placenta cows in which successful immune assisted detachment of the foetal membranes occurs.  相似文献   

10.
Milk progesterone measurements were used to study post-partum ovarian activity and risk factors for ovarian dysfunction in Zebu cows reared under a traditional pastoral management system in three villages in Morogoro region, Tanzania. Milk samples for progesterone analysis were collected twice per week from a total of 98 lactations. The most prevalent ovarian dysfunction detected was delayed onset of post-partum ovarian activity and cessation of cyclical ovarian activity after a period of normal ovarian function. Prolonged luteal phases were not observed. Resumption of post-partum ovarian activity was observed in 61 (62.2%) cows. Pregnancy was diagnosed in 43 (43.8%) out of 98 cows and was terminated by abortion in 7 (16.3%) cows. The median number of days from calving to resumption of ovarian activity was lower in cows that calved during the dry season (167 days) as compared with those that calved in the rainy season (200 days, P=0.03), probably because ovarian function was stimulated in cows entering the rainy season first after the puerperal phase had ended. Cyclical ovarian activity ceased in seven (11.5%) cows, and all but one case of cessation of ovarian activity took place during the dry season. Cows in their first and second parities experienced prolonged intervals (244 days) between calving and onset of ovarian activity compared with cows in their third or later parity (172 days, P=0.03). Cows with marked losses in body condition experienced prolonged intervals between calving and onset of ovarian activity (229 days) as compared with cows that lost <1 body condition unit (172 days, P=0.03). The time interval from calving to resumption of ovarian activity varied between the three villages of the study (142, 192 and 229 days, P=0.05), indicating local differences in management practices.  相似文献   

11.
The structure of genetic polymorphism of the blood and milk proteins and blood enzymes was studied. It was shown that in the Western region of Ukraine Black-and-White breed cattle had seven phenotypes of transferrin, one phenotype of hemoglobin, three phenotypes of amylase, five phenotypes of alkaline phosphatase, ceruloplasmine, beta-lactoglobuline, and alpha si-caseine, and three phenotypes of beta-caseine. The effects of homo- and heterozygous levels on the heifer growth, milk production and fertility of cows were found. Complex analysis of polymorphism of blood and milk ferments and proteins gives possibility to find a closer association of genetic tests with growth, milk production, and fertility of animals of Black-and-White breed.  相似文献   

12.
The Australian dairy herd size has doubled over the last 20 years substantially increasing the time that farmers require for individual animal attention to monitor and intervene with events such as calving. Technology will help focus this limited labour resource on individual cows that require assistance. The objective of this experiment was to first determine the profiles of rumination duration and level of activity as determined by sensors between, and within, days around calving and second to use these data to predict the day of calving for pasture-based dairy cows. After 2 weeks from the expected calving date, 27 cows were fitted with SCR HR LD Tags, located in 40×90 m2 paddock and offered ad libitum oaten hay and 2 kg grain-based concentrate/cow per day until calving. Hourly activity and rumination data for each cow, as determined by the SCR tags, were fitted with linear mixed models and all parameters were estimated using restricted maximum likelihood. Rumination duration decreased by 33% over the day prior and the day of calving, with the decline in rumination duration starting the day prepartum. Activity levels were maintained prepartum but increased in the days postpartum. The day of calving was recorded and used to determine the gold standard positive (the day before calving) and negative (all other) dates. A threshold rumination level of 0.9 (decline in rumination duration of 10%) gave the optimal combination of 70% sensitivity and 70% specificity. This experiment shows the potential to use rumination duration to predict the day of calving and the opportunity to use sensor data to monitor animal health.  相似文献   

13.
A national sample of cow-calf producers was contacted to participate in a study to describe selected calving management practices on operations throughout the United States. Information was gathered on calving season, frequency of dystocia, frequency of observation, timing of assistance, and calving facilities. Regional and herd size differences existed in all parameters evaluated. Most calves (63.9%) were born in the months of February, March, and April. Overall, 16.7% of heifers and 2.7% of cows required some level of assistance in calving. Heifers and cows were checked an average of only 3.6 and 2.5 times per 24 h period during the calving season. Producers allowed heifers to labor for an average of 2.8h prior to lending assistance in calving while cows were allowed an average of 3.5h before providing assistance. In addition, only 39.6% of calvings took place in specialized calving areas presumably to allow increased observation frequency, timely intervention and protection from the elements. Collectively, these management practices illustrate that opportunities exist to improve calf survivability and increase reproductive efficiency in many cow herds.  相似文献   

14.
The objective of this study was to determine the efficacy of PGF2 alpha treatment on pregnancy and calving rates in autumn-calving suckler beef cows synchronized with progesterone and eCG. The population studied consisted of 124 Charolais and 130 Limousin cows in 13 and 12 beef herds, respectively. In each herd, pairs of cows were formed according to parity, body condition score and calving difficulty. Group 1 received a progesterone releasing intravaginal device (PRID) for 12 d with a capsule containing 10 mg estradiol benzoate at implant insertion and 500 IU eCG at PRID removal (Day 0). Group 2 received the same treatment plus 25 mg i.m. dinoprost at Day -2. Each cow was artificially inseminated 56 h after PRID removal (Day 3). Plasma progesterone concentrations were measured to determine cyclicity prior to treatment in samples take on Days -22 and -12, to confirm the occurrence of ovulation (Day 13) and to determine the early pregnancy rate (Day 26). Serum pregnancy-specific protein B (PSPB) concentrations were determined to assess pregnancy rate at Day 39. The effects of variation factors on pregnancy and calving rates after treatment were studied using logistic mixed models and a Cox model, respectively. There were no significant differences between groups or breeds for the rate of cyclicity before treatment nor for ovulation rate (means, 74.1 and 95.7%, respectively). Cyclicity was, however, influenced by individual factors such as body condition score (OR = 3.36, P = 0.001), parity (OR = 5.4, P = 0.001) and herd factors such as stocking rate (OR = 5.62, P = 0.001). The use of a prostaglandin injection increased pregnancy rate at Day 26 (71.7 vs 56.7%, P = 0.01) and at 39 d (67.7 vs 54.3%, P = 0.02) and the calving rate at induced estrus (64.5 vs 48.5%, P = 0.01). We observed 9 twin calvings (5.6%) which occurred in cyclic cows only before treatment. Cows in Group 2 had a 1.5 greater chance of calving before 300 d following the first AI than cows in Group 1 (P = 0.03). In conclusion, the addition of PGF2 alpha injection, 48 h before PRID removal, increased reproductive efficiency in autumn-calving Charolais and Limousin suckler beef cows compared to a classical estrus synchronization treatment using a PRID + eCG.  相似文献   

15.
牛RXRG基因遗传变异与双胎性状的关联分析   总被引:1,自引:0,他引:1  
黄萌  许尚忠  昝林森  张路培  高雪  陈金宝 《遗传》2008,30(2):190-194
以视黄素X受体基因g(retinoid X receptor-gamma, RXRG)作为牛双胎性状的候选基因, 运用测序法寻找牛RXRG基因SNPs, 筛查到一个新的多态位点A1941G, 该位点位于3′UTR。运用PCR-RFLP法验证并分析该位点在鲁西牛双胎群体和单胎群体及中国西门塔尔牛、安格斯牛和西蒙杂交牛单胎群体间的多态性, 结果表明, 在鲁西牛双胎和单胎群体中分布A、B两个等位基因,处于中度多态。经χ2适合性检验, 鲁西双胎牛群体在该位点未达到Hardy-Weinberg平衡状态(P < 0.05)。将鲁西牛群体的A1941G位点的基因型效应与双胎性状进行关联分析, 卡方独立性检测结果显示, 基因型分布在鲁西单、双胎牛群体上差异达到极显著水平(P < 0.01)。  相似文献   

16.
Ninety two Friesian cows were used to determine physical properties of cervical mucus collected during normal estrus and estrus induced. Estrus was induced using either progesterone (P4) releasing intravaginal devices (PRID) and/or prostaglandin F2alpha (PGF2alpha). The animals were assigned to 4 groups (no treatment, a PRID for 12 days plus an injection of 1000 IU PMSG at the removal of the PRID, a double injection of 3 mL PGF2alpha 11 days apart, and a PRID for 7 days plus an injection of PGF2alpha 24 h before the removal of PRID). A number of cows with normal estrus exhibited three consecutive estrus cycles after calving. Cows that had not shown estrus for three months after calving had their reproductive system palpated twice at 10-day intervals, to determine their ovarian activity. Then PRID and/or PGF2alpha was administered to cows that were found to have a palpable corpus luteum in one of two palpations (cycling cows). The cows of the three induced estrous groups were artificially inseminated (AI) twice, while those with normal estrus received only a single AI. Cervical mucus samples were collected from all cows 5 to 30 min before the first AI. Additionally, samples of cervical mucus were collected from 20 cows at their first estrus after the induced estrus. The results are summarized as follows: 1) The physical properties of cervical mucus were similar in the first three normal consecutive estrus cycles after calving. 2) The physical properties of cervical mucus in normal estrus after calving were similar to those in the first estrus after an induced estrus. 3) The pH values for normal estrus were similar to those for induced estrus. 4) Viscosity of cervical mucus in the normal estrous group was significantly lower than that in the induced estrus. Furthermore, significant differences were noticed among the three induced estrous groups. 5) Spinnbarkeit, crystallization and receptivity of cervical mucus (penetration test) were significantly higher in the normal estrous group than in the induced estrous groups, while no difference was detected among induced estrus groups. 6) Pregnancy rates in the normal estrus group were the same as in the induced estrus groups. 7) The percentages of cows in the induced estrous groups that produced cervical mucus with similar viscosity, spinnbarkeit and receptivity (penetration test) characteristics as the normal estrus group, was very low.  相似文献   

17.
Whereas neutrophils are the main phagocytic leukocytes, monocytes and macrophages are actively involved in immunomodulation after infection. Recent studies have demonstrated that neutrophil function is impaired by the state of negative energy balance around parturition, and that cows that develop uterine disease have a greater degree of negative energy balance than healthy cows. The objectives of this study were to compare monocyte gene expression and protein secretion of selected cytokines from calving to 42 d after calving in Holstein cows that did or did not develop uterine disease. Real time quantitative RT-PCR (Tumor necrosis factor-α (TNFα), Interleukin (IL)-1β, IL-6, IL-8 and IL-10) and ELISA (TNFα, IL-1β and IL-8) were used to evaluate cytokine response following in vitro stimulation of blood-derived monocytes with irradiated E. coli. Relative to unstimulated cells, E. coli-stimulated monocytes from cows with metritis had lower gene expression of key pro-inflammatory cytokines than healthy cows from calving to 14 d after calving (TNFα at 0, 7, and 14 d after calving, IL-1β and IL-6 at 7 and 14 d after calving; P < 0.05). There were no significant differences between groups for expression of IL-8 or the anti-inflammatory cytokine IL-10. This was due, in part, to higher gene expression in unstimulated monocytes (TNFα, IL-1β, IL-6 and IL-10) in early lactation from cows with metritis. Expression of mRNA in stimulated cells (relative to housekeeping genes) was lower for TNFα (7 and 14 d postpartum) and for IL-10 (7 and 14 d postpartum) in cows with metritis. Concentration of TNFα was lower in the culture medium of E. coli-stimulated monocytes from cows with metritis than healthy cows at calving and 7 and 21 d after calving (P < 0.05). Circulating cytokine concentrations were not different between groups for IL-8 and were below the limits of detection for TNFα and IL-1β. Cytokine gene expression and production were similar between healthy cows and cows that developed endometritis, diagnosed cytologically at 42 d after calving. We concluded that altered levels of expression and production of pro-inflammatory cytokines postpartum could contribute to impaired inflammatory response and predispose cows to development of metritis.  相似文献   

18.
Image and cytochemical analyses were undertaken to determine possible correlation between the number and size of acid phosphatase-positive granules (lysosomes), and variation in acid phosphatase (AcP) activity in the proximal tubule cells of mouse-kidney during growth and development. Eighteen ddY strain mice ages: 1 day, 1 and 2 weeks, and 1, 2 and 10 months were used. The lanthanide-based method for the ultrastructural localization of AcP-activity was employed. The number and size of AcP positive granules were quantitatively analyzed by image analysis, and AcP activity by X-ray microanalysis. Significance was evaluated by 2-tailed-Student's t-test for the difference between means. AcP activity was observed in the lysosomes and the reaction product appeared dense and heterogeneous. In some cells, it appeared apparently homogeneous. The results showed that the number and size of AcP Positive granules (lysosomes) increased significantly from the first day after birth, recorded a peak in one week time and thereafter, it gradually declined until the 10th month. The result of X-ray microanalysis demonstrated a variation in accordance with the degree of AcP activity at different ages of the animals studied. The AcP activity decreased significantly from day one and progressively until the 10th month. From the results of the present work, it could be inferred that the changes in size and number of AcP positive granules, at least, at the early stage, and/or the variation in AcP activity are related to the growth and development of the animal.  相似文献   

19.
The postpartum period is crucial in dairy cows and is marked by major physiological and metabolic changes that affect milk production, immune response and fertility. Nutrition remains the most important lever for limiting the negative energy balance and its consequences on general health status in highly selected dairy cows. In order to analyze the effect of a commercial micronutrient on intrinsic parameters, performances and the epigenome of dairy cows, 2 groups of 12 Holstein cows were used: 1 fed a standard diet (mainly composed of corn silage, soybean meal and non-mineral supplement) and the other 1 fed the same diet supplemented with the commercial micronutrient (µ-nutrient supplementation) for 4 weeks before calving and 8 weeks thereafter. Milk production and composition, BW, body condition score (BCS), DM intake (DMI) and health (calving score, metritis and mastitis) were recorded over the study period. Milk samples were collected on D15 and D60 post-calving for analyses of casein, Na+ and K+ contents and metalloprotease activity. Milk leukocytes and milk mammary epithelial cells (mMECs) were purified and counted. The viability of mMECs was assessed, together with their activity, through an analysis of gene expression. At the same time points, peripheral blood mononuclear cells (PBMCs) were purified and counted. Using genomic DNA extracted from PBMCs, mMECs and milk leukocytes, we assessed global DNA methylation (Me-CCGG) to evaluate the epigenetic imprinting associated with the µ-nutrient-supplemented diet. The µ-nutrient supplementation increased BCS and BW without modifying DMI or milk yield and composition. It also improved calving condition, reducing the time interval between calving and first service. Each easily collectable cell type displayed a specific pattern of Me-CCGG with only subtle changes associated with lactation stages in PBMCs. In conclusion, the response to the µ-nutrient supplementation improved the body condition without alteration of global epigenetic status in dairy cows.  相似文献   

20.
Ten evolutionary conservative sequences with high identity level to homological sequences in other mammal species were revealed in 5'-flanking region of casein's genes cluster. Five novel SNPs located inside of the evolutionary conservative regions were identified. The binding sites were revealed to be present in one allelic variant of four detected SNPs. So these SNPs were considered as rSNPs. Significant differences of allelic frequencies were revealed between beef cow's group and dairy cow's group in two rSNPs (NCE4, NCE7, p<0.001). Different alleles of those two rSNPs were shown to be associated with some milk performance traits in Black-and-White Holstein dairy cows. Significant difference of protein percentage has been found between cows with G/G and A/A genotypes (P<0.05) and A/G and A/A genotypes (P<0.05) for NCE4 polymorphism. The groups of animals with genotypes G/G and A/G for NCE7 polymorphism were significantly different in milk yield at the first lactation (kg) (P<0.01), milk fat yield (kg) (P<0.05) and milk protein yield (kg) (P<0.01). For the last trait the difference was significant also between cows with genotypes G/G and A/A for rSNP NCE7 (P<0.05).  相似文献   

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