Proteomic analysis of mammary tissues from healthy cows and clinical mastitic cows for identification of disease-related proteins

To investigate the disease-related proteins and understand molecular mechanism of mastitis at the protein level, this project presents the protein changes in the mammary gland between healthy cows and clinical mastitic cows using two-dimensional gel electrophoresis (2-DE), after stained with colloidal Coomassie Bright Blue, six spots of differentially expressed protein were detected by PDQuest software and subjected to ion trap mass spectrometer equipped with a HPLC system, and five proteins were identified. Hemoglobin beta, kappa-casein and tryptophanyl-tRNA-synthetase (TrpRS) in healthy dairy cows, while hemoglobin beta, cytochrome C oxidase and annexin V in clinical mastitic cows were identified, they were involved in binding, transport and catalytic activity. The results may provide valuable information for the investigating of the host mammary immune system response to defense against pathogens at the protein level and potential protein targets for treatment.     

Associations of sole ulcer at claw trimming with reproductive performance, udder health, milk yield, and culling in Swedish dairy cattle

The association between sole ulcer found at routine claw trimming 2–6 months after calving and reproductive, health and productive traits in the same lactation, was investigated in an observational study of 2368 dairy cows in 102 Swedish herds. The data were analysed by mixed multivariable linear-, logistic- and Poisson-regression modelling at the cow level, accounting for clustering within herd. Associations were found between sole ulcer and first-service conception risk in the first study year (OR 0.59), calving interval (2% longer), treatment for anoestrus (OR 1.61), and 305-day milk yield (479 kg ECM higher). No associations could be shown between sole ulcer and first-service conception risk in the second study year, the number of services per conception, clinical mastitis, high milk somatic-cell counts or culling.     

Milk hygiene and udder health in the periurban area of Hamdallaye, Niger

The prevalence of intra-mammary infections in dairy herds was studied in Hamdallaye, Niger. A total of 956 milk samples were collected in 2007 from 239 lactating cows of four local breeds in eight traditional herds; the first sampling was undertaken in the dry season at morning milking, and the second in the rainy season at evening milking. Staphylococcus aureus, Coagulase-Negative Staphylococci (CNS) and environmental microorganisms were detected in significantly (p < 0.05) more samples in the rainy season, 55.2%, than in the dry season, 27.1%. Statistically significant (P < 0.05) differences in prevalence were observed among herds and according to lactation number. Infections were assigned to four classes, according to the major pathogen, and the respective mean somatic cell counts during the dry season were: S. aureus, 775 × 10³ cells/ml; CNS, 447 × 10³ cells/ml; environmental microorganisms, 407 × 10³ cells/ml; and non-infected, 262 × 10³ cells/ml. Most of the tested strains were sensitive to antibiotics, and selected strains of S. aureus (n = 15) were negative to the multiplex PCR tests for production of enterotoxins.     

Relationship between the somatic cell count in milk and reproductive function in peripartum dairy cows

The aim of the present study was to examine the effect of the somatic cell count (SCC) in milk on reproductive performance, such as pregnancy status in the prepartum period and ovarian function in the postpartum period, in dairy cows. Blood samples were collected every week from one month prepartum to parturition in order to measure the concentrations of 13,14-dihydro-15-keto-PGF_2α (PGFM), estrone sulfate (E1S) and progesterone. Milk samples were collected three times per week in both the prepartum (for one month before the dry period) and postpartum periods (for 3 months immediately after parturition) to measure the SCC. Progesterone was also determined in the whole milk of postpartum cows to define the day of the first ovulation. In the prepartum period, the maximum SCC negatively correlated with the pregnancy period (r = –0.77), but not the calf birth weight. Positive and negative correlations were observed between the average SCC and PGFM or progesterone concentrations in plasma, respectively (r = 0.84 or –0.92, respectively), at 39 weeks of pregnancy. In the postpartum period, a correlation was observed between the day of the first ovulation and both the average and maximum SCC (r = –0.74 and –0.75, respectively), whereas days open was not related to the SCC. These results suggest that a high SCC in the prepartum period may advance parturition by increasing PGF_2α and decreasing progesterone and that the first ovulation in the postpartum period was affected by a high SCC.     

急性期蛋白及其在奶牛乳房炎发展中的作用

急性期蛋白(Acute Phase Protein,APP)属于血液蛋白的一种,检测其水平可作为一种估计动物机体对疾病的先天性免疫反应的方法。当炎症、感染和创伤发生时,动物血清急性期蛋白浓度会增加或减少25%以上,它可以作为判断预后、评价治疗效果、衡量动物健康和诊断疾病方面的定量标记物。就像直肠温度一样,虽然不能对疾病进行特异性诊断,而且影响因素较多,但在机体受到病理损伤时,却具有极高的敏感性。当奶牛发生乳房炎时,可以分析其血清和乳汁中急性期蛋白的水平,监督乳房组织的炎症状态。     

Serum constituents analyses in dairy cows: effects of duration and temperature of the storage of clotted blood

We studied the effects of storage time and temperature of clotted whole blood on the amounts of 17 analytes in bovine blood serum. Serum separated after blood was allowed to stand for 2, 4, 6, 12 and 24h at room temperature or on ice. Results obtained for phosphorous, magnesium, urea, cholesterol, beta-hydroxybutyrate (BHBA), triglyceride, albumin, total protein and gamma-glutamyletransferase (GGT) were not influenced by storage at room temperature or on ice for as long as 24h. Duration of the clotted whole blood storage had a significant effect on calcium, glucose concentrations, creatine kinase (CK) and aspartate aminotransferase (AST) activities and temperature had a significant effect on glucose, non-esterified fatty acids, CK and bilirubin concentrations.     

Associations between use of electric cow-trainers and clinical diseases, reproductive performance and culling in Swedish dairy cattle

The aims of this follow-up study were: (a) to evaluate the role of ECT technology as a risk factor for several diseases; and (b) to determine if the effects of these diseases on cows' reproductive performance and as risk factors for culling are influenced by exposure to ECTs. Diseases considered were retained placenta, metritis, ketosis, cystic ovaries, silent heat, milk fever, clinical mastitis, and foot and leg problems. We used historical and contemporary controls (with control herds selected to match the experimental herds for size and location). Data consisted of 10264 Swedish Red and White (SRB) and 5461 Swedish Friesian (SLB) lactation records in 150 herds of which 33 used cow-trainers. Logistic regression was used to estimate the effects of parity and exposure to electric cow-trainers on the risks of diseases and the effects of diseases and exposure to electric cow-trainers on risk of culling. The least-squares procedure was used to estimate the effects of diseases on reproductive performance.

The dominant effects associated with use of electric cow-trainers were an increased risk for silent heat, clinical mastitis, ketosis and culling relative to cows in herds not using cow-trainers. Diseases had negative effects on reproductive performance and the effects were larger for cows in herds using cow-trainers. In herds using electric cow-trainers, the largest increase in the interval from first service to conception (58 days) was caused by the occurrences of silent heat, cystic ovaries and the combination of two or more diseases. Retained placenta, metritis, cystic ovaries, clinical mastitis and a combination of two or more diseases increased the risk of culling about two times relative to healthy primiparous cows with the increase being greater for cows in herds using cow-trainers. Silent heat did not increase risk of culling in control groups, but was the largest risk factor for culling in the exposed group. We concluded that exposure to electric cow-trainers increased the incidence risk of silent heat, clinical mastitis, and ketosis and changed silent heat from a neutral disease with respect to culling to a major risk factor. Finally, exposure to cow-trainers increased the general negative effect of diseases on the cows' reproductive performance and risk for culling.     

The effect of parenteral supplementation of vitamin E with selenium on the health and productivity of dairy cattle in the UK

Recent work has suggested that the recommended intakes of vitamin E for dairy cattle need to be increased, particularly in dry cows. However, these suggestions are based on data from cattle in the USA, which may have significantly different oxidative stresses than European cattle. This study, which involved 594 cattle on three dairy farms, was designed to determine the effect of increased vitamin E supplementation on the health and fertility of UK dairy cows. Cattle were randomly allocated to receive either two intramuscular injections of 2100 mg of vitamin E (and 7 g of sodium selenite) 2 weeks before calving and on the day of calving, or no additional vitamin E supplementation. Although supplementation had no effect on milk yield, reproductive efficiency, or incidence of uterine infections, supplemented cattle had a lower risk of culling and a lower rate of mastitis. These figures were economically significant but not statistically significant at the 10% level. Supplementation reduced the incidence of retained fetal membranes from 6.5% to 3%, an effect which was almost significant at the 5% level. If these data are representative they suggest that vitamin E recommendations for UK cattle should be reassessed.     

An economic analysis of hyperketonemia testing and propylene glycol treatment strategies in early lactation dairy cattle

The purpose was to develop stochastic economic models which address variation in disease risks and costs in order to evaluate different simulated on-farm testing and propylene glycol (PG) treatment strategies based on herd hyperketonemia (HYK) incidence during the first 30 DIM. Data used in model development concerning the difference in health and production consequences between HYK and non-ketotic cows were based on results from 10 studies representing over 13,000 cows from 833 dairy farms in North America, Canada, and Europe. Inputs for PG associated variables were based on a large field trial using cows from 4 free-stall dairy herds (2 in New York and 2 in Wisconsin). Four simulated on-farm testing and treatment strategies were analyzed at herd HYK incidences ranging from 5% to 80% and included: 1) treating all cows with 5 d of PG starting at 5 DIM, 2) testing all cows for HYK 1 day per week (e.g. Mondays) from 3 to 16 DIM and treating all positive cows with 5 d of oral PG, 3) testing all cows for HYK 2 days per week (e.g. Mondays and Thursdays) from 3 to 9 DIM and treating all positive cows with 5 d of oral PG, and 4) testing all cows for HYK 3 days per week (e.g. Mondays, Wednesdays, and Fridays) from 3 to 16 DIM and treating all positive cows with 5 d of oral PG. Cost-benefit analysis included the costs associated with labor to test cows, β-hydroxybutyrate test strips, labor to treat cows, PG, and the associated gain in milk production, decrease in DA and early removal risks of PG treated HYK positive cows compared to non-treated HYK positive cows. Stochastic models were developed to account for variability in the distribution of input variables. Per 100 fresh cows in a herd with an HYK incidence of 40%, the mean economic benefits of the 4 different strategies were $1088, $744, $1166, and $760, respectively. Testing cows 2 days per week from 3 to 9 DIM was the most cost-effective strategy for herds with HYK incidences between 15% and 50%; above 50%, treating all fresh cows with 5 d of PG was the most cost-effective strategy. These results show that for herds similar to those used in model, when herd HYK incidences rise above 25%, almost any HYK testing and treatment protocol will be economically beneficial for the farm.     

蒲公英散与抗生素治疗奶牛乳房炎的比较试验

近几年,长期大量使用抗生素和化学药品治疗奶牛乳房炎,凸显出了药物残留、耐药性等影响人类健康的问题,中药方剂治疗奶牛乳房炎已成为当前研究的热点。本研究进行了蒲公英散与抗生素治疗奶牛乳房炎的临床比较试验,结果表明,蒲公英散的治愈率显著高于抗生素,也解决了抗生素治疗的残留、耐药、休药、弃奶等问题。     

Genetic analysis of protein yield,udder health,and female fertility in first-parity Danish Holstein cows

Abstract

Genetic parameters for protein yield, clinical mastitis, SCS, number of inseminations (NI), and days from first to last insemination (FLI) were estimated for first-parity Danish Holstein cows. The objective was to estimate genetic correlations between the five traits mentioned above and to study whether NI and FLI are measures of the same trait. Records containing information on approximately 200 000 cows were analysed using tri-variate animal models. The genetic correlations between the udder health traits and the fertility traits were favourable and in the range from 0.17 to 0.42, whereas the genetic correlations between protein yield and the fertility traits were unfavourable and ranged from 0.43 to 0.52. These results highlight the importance of continuing to emphasize functional traits in future breeding programmes. The genetic correlation between the fertility traits was 0.82. Based on this result, it cannot be concluded that NI and FLI are measures of the same trait.     

Welfare-positive management and nutrition for the dairy herd: A European perspective

As European dairy farms become larger and diverge between grass-based and fully housed systems, interest in the welfare of the dairy cow and related environmental issues by consumers and legislators is increasing. These pressures mean that good nutrition and management, which underpin much dairy cow welfare, is critical. Despite considerable research into the management and nutrition of the dairy cow from calf to adulthood there is much on-farm variability in its application. While the incidences of many endemic diseases are reduced most are still significant, for example lameness. In addition, trade and climate change are bringing a more diverse range of pathogens, parasites and pests into Northern Europe. Housing aspects are limited in application by economics and in most cases still do not match grazing for welfare in temperate climates. Genomic technologies offer increased opportunities to breed for ‘robustness’ but like ‘precision animal management systems’ have still to be fully exploited.     

中国荷斯坦后备奶牛生长发育规律的研究

通过对西安现代化农业开发公司草滩农场170头荷斯坦牛后备牛初生,4月龄至16月龄体高、体长、胸围及体重进行测定,统计各月龄体高、体长、胸围及体重的累积生长的平均值、绝对生长值、相对生长值,对应绘制出四项指标的累计生长、相对生长曲线;分析了西安地区中国荷斯坦牛的早期生长发育状况,为制定后备牛的培育方案奠定了基础。     

Effects of three short-term pasture allocation methods on milk production,methane emission and grazing behaviour by dairy cows

Two short-term grazing experiments were conducted with Norwegian Red cows. In Exp 1, 24 cows were randomly assigned to one of the following three pasture allocation methods (PAM): weekly pasture allowance (7RG), grazing 1/7 of 7RG each day (1SG), or grazing as 1SG but had access to grazed part of the paddock within one week (1FG). In Exp 2, 7RG was shortened to 5 days (5RG). We hypothesized that PAM will affect sward quality, quantity, intake and production differently. Pasture chemical composition changed with advancing grazing days but were not different between treatments. Pasture intake, milk yield, and methane emission were not affected by PAM. In Exp 1, 7RG cows spent less time on grazing, whereas in Exp 2, 1FG cows spent longer on grazing than others. Patterns observed in sward quality, and behavioural and physiological adaptations of cows to short-term changes in nutrient supply may explain the observed effects.     

中西药结合治疗奶牛乳房炎试验

分别采用中药、西药及中西药结合进行奶牛乳房炎治疗试验。结果表明,中西药结合治疗奶牛乳房炎具有较好的作用,其治疗效果优于西药。中西药结合治疗奶牛隐性乳房炎治愈率高达100%,效果十分显著。     

Effect of twinning on the feed intake, performance and health of dairy cows

The aim of this study was to assess the effect of bearing twins on the health and performance of dairy cows. Data from twin-bearing Holstein Friesian cows at the Langhill Dairy Research Centre between January 1990 and July 2002 were compared to single-bearing cows to determine if there was any significant difference in milk production, feed intakes, health and fertility. There were 122 twin births (from 104 different cows) in the Langhill herd, a rate of 4.7% during the study period.

The incidence of twinning was higher in high genetic merit cows (select genetic line cows) and increased with parity (r = 0.870, P < 0.01). Compared to a single-bearing cow, a twin pregnancy was associated with a shorter gestation period, an increased chance of a retained placenta after calving and a poorer body condition score post-calving. The post-calving condition score of twin-bearing cows was negatively correlated with the total weight of calves born (r = − 0.235, P < 0.05). Twin-calving cows also had significantly more dystocia, a higher chance of having a dead calf, an increased number of days from calving to their first observed heat and number of days from calving to their first service. Dystocia was positively correlated with the number of dead calves at birth (r = 0.309, P < 0.01) and with the total weight of calves born (r = 0.211, P < 0.05). Twin-bearing cows on a low-concentrate diet had an increased chance of having metritis and/or endometritis compared to single-bearing cows on the same diet. There was no significant difference in the reason for culling or the time at which cows were culled post-calving, however, twin-bearing cows on a low-concentrate diet were 3.2 times more likely to be culled than a single-bearing cow, with cows on a high-concentrate diet having equally high levels of culling. There were no significant differences between twin- and single-producing cows' mean daily feed intakes, daily milk yields, total milk yields and milk fat and protein compositions during early, mid and late lactation pre and postpartum on a low- or high-concentrate diet. The body condition and drying off period of twin pregnant cows should be managed to avoid post-calving health and performance problems.     

Balancing diets for physically effective fibre and ruminally degradable starch: A key to lower the risk of sub-acute rumen acidosis and improve productivity of dairy cattle

Finding an optimal balance between the amount of physically effective fibre and rumen fermentable carbohydrates in the diets of high-producing dairy cows is difficult, but critical to prevent sub-acute ruminal acidosis (SARA), optimize digestion, nutrient utilization, and improve productivity. The main aim of the present review was to provide a summary of recent achievements regarding the role that interactions between dietary factors such as grain fermentability and physically effective neutral detergent fibre (peNDF) have on rumen fermentation and SARA as well as on production performance in high-producing dairy cows. The review first considers factors related to grain fermentability and finds that the latter variable depends mainly on the source of starch as well as in processing and conservation method; however, dairy cow's response to grain fermentability should be considered in relation with the total amount of starch and/or concentration of peNDF in the diet. Forages and current methods used in the evaluation of their physical characteristics were also reviewed suggesting the use of Penn State Particle Separator as an adequate approach to determine the distribution of particle fractions as well as the content of peNDF in both forages and total mixed rations. Furthermore, results reviewed in this study suggest that a content of peNDF_> 1.18 (expressed inclusive of particles-dry matter > 1.18 mm) in the diet of about 30–32% is sufficient in maintaining a daily mean of ruminal pH of 6.2, lowering the risk of SARA, and preventing milk fat depression without exerting any negative effects on daily feed intake and milk production. The review concludes with a practical recommendation in terms of balancing diets with peNDF_> 1.18 and ruminally degradable starch, suggesting that a ratio between the two variables lower than 1.45 should be avoided when formulating diets for lactating dairy cows.