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1.
In a comparison of Holstein Friesian (HF) from North America with Dutch Red and Whites (DRW) and Dutch Friesians (DF), the feed intake of 20 animals per breed was measured at different stages of lactation and at different ages. In the experiments with dairy cows, the animals were offered concentrates individually according to their milk yield. In all experiments roughage (silage or hay) was offered ad libitum.In all experiments the DRW animals ate less roughage than the HF and DF animals, although they ate the lowest amount of concentrates in nearly all experiments, due to their lower milk yield. The HF animals were offered more concentrates than the DF animals, but ate the same amount of roughage.  相似文献   

2.
The effect of oestrus on milk production in cows   总被引:2,自引:0,他引:2  
The rectal temperatures, pulse rates and milk yields of 44 Ayrshire and 38 Friesian cows were recorded during oestrus and compared with values obtained after oestrus had ceased. The fat, solids-non-fat (SNF) and protein percentages and the cell counts of milk samples were also compared. Forty of the cows were housed in cubicles and 42 were kept loose in yards. During oestrus rectal temperatures and pulse rates were significantly raised and milk yields were lowered. Milk had, on average, significantly higher fat contents and cell counts and lower SNF and protein contents than post-oestrous milk. The differences due to oestrus between the cows kept in cubicles and yards were minimal, but the Ayrshire cows tended to show more significant effects than the Friesians, except in the milk cell counts, where the difference was higher in the Friesians.  相似文献   

3.
Production characteristics of purebred Holstein Friesians (HF), Dutch Friesians (DF) and Dutch Red and Whites (DRW) were compared to determine the genetic differences between the three breeds under Dutch production systems. In the first, second, and subsequent lactations, HF animals produced, respectively, 18.8, 20.7 and 18.8% more milk and 10.5, 11.1 and 9.8% more fat and protein than the DF animals. The DRW animals produced 7.3, 7.0 and 6.4% less milk and 7.2, 7.1 and 5.9% less fat and protein in the first three lactations, respectively, than the DF animals.In beef and veal production the HF animals had a slightly less efficient conversion of feed to gain than the DF animals, but the feed conversion of the DRW was better than that of the DF animals. Slaughter quälity traits (dressing percentage and fleshiness) were lowest for the HF animals in all slaughter categories and highest for the DRW animals. Carcass weights averaged 305 kg for HF cows, 285 kg for DF cows and 297 kg for DRW cows. For the HF, DF and DRW cows, percentages of calves born alive were, respectively, 88.6, 93.9 and 87.0%; birth weights were, respectively, 42.7, 36.2 and 39.2 kg; days of pregnancy were, respectively, 282.2, 276.9 and 278.0; and inseminations per pregnancy were respectively, 1.91, 1.55 and 1.59. Other averages for HF, DF and DRW were, respectively, age at first calving 778, 748 and 759 days; first calving interval 400, 370 and 387 days; and later calving intervals 389, 374 and 381 days. Significant differences in disease frequencies and reasons for calling were observed between the breeds.  相似文献   

4.
Data from 321 spring-calving cows (mean calving date March 27) were used to assess the effects of body condition, live weight, cow age (from 4 to 13 yr), and breed (237 Hereford x Friesians and 84 Blue-Greys) and time of calving on the proportion of cows that became pregnant, the number of days from the start of mating to pregnancy, and calving interval. Mating started at turn-out to pasture in mid-May and lasted 9 to 10 wk. Body condition at calving and breed were the most significant animal factors affecting reproductive performance. Cows calving in higher body condition had shorter (P less than .001) calving intervals (11.2 d per unit of body condition at calving). Blue-Grey cows became pregnant in a higher proportion (90%) and calving interval was shorter (364 d) than in Hereford x Friesians (83%; 374 d). Body condition at the start of mating was less important and body condition at the end of mating had no effect. Live weight at calving and changes in live weight from calving to the start of mating and during the mating period had no significant effect. The proportion of cows becoming pregnant decreased significantly with age in Hereford x Friesian cows older than 7 yr. The variance in calving interval accounted for by calving date, body condition at calving, breed, and age was 42%.  相似文献   

5.
In the second generation of a crossbreeding experiment with Holstein Friesian bulls and Dutch Friesian cows the difference in additive genetic merits between Holstein Friesian and Dutch Friesian bulls (a), the heterotic effects (d) and the maternal effects (m) were calculated from the mean values of the four subpopulations with 0%, 25%, 50% and 75% Holstein Friesian genes. Significant a effects were found for milk yield, fat percentage, fat yield, protein yield, fleshiness (beef bulls and veal calves), fat covering (beef bulls), dressing percentage (veal calves), birth weight, percentage of calving difficulties and gestation period. A significant d effect was found for fat covering (beef bulls). For dressing percentage (veal calves), for the percentage of calving difficulties and of retained placenta, significant m effects were calculated.  相似文献   

6.
The effect of the environmental level of production (ENV) on the expression of heterosis for 305-day milk, fat, protein, and fat plus protein (FP) yields, lactation average somatic cell score (LSCS), and age at first calving (AFC) was investigated in first lactation Black and White dairy cows in the Netherlands, and officially enrolled in the Dutch herd-book. Holstein Friesian (HF), Dutch Friesian (DF), and first generation (F1) crosses obtained from the mating of HF sires and DF dams (HD) were involved in the study, and data from animals with a calving date between 1990 and 2000 were used. A total of 22,930 cows with production and AFC information distributed in 3549 herds and 11,055 cows with LSCS information distributed in 2071 herds, were available. Adjusted lactation yield of milk for each herd was obtained using a model that accounted for fixed effects of herd, year and month of calving, genotype, and AFC. The overall mean of all adjusted data was computed, and 3 ENV were defined on the basis of the overall mean ± 0.5 standard deviations. Once ENV was defined, traits were analysed with a model that included fixed effects of ENV, herd nested within ENV, AFC (only production traits and LSCS), year and month of calving, genotype, and the interaction between ENV and genotype. Least squares means for the interaction effect were used to estimate heterosis and to evaluate its magnitude across ENV. Holstein Friesian achieved higher productions than DF. First generation crosses showed productions close to HF, especially in the low ENV. Estimates of heterosis for yield traits ranged from 2.4% (milk) in the high to 5.3% (fat) in the low ENV, and reduced with increasing ENV. Estimates for LSCS and AFC were low, with the exception of LSCS in the high ENV. Results suggest that the highest non-additive genetic effects for yield traits and LSCS were expressed in the most stressful ENV, i.e., the low one for production and the high one for LSCS.  相似文献   

7.
Eleven primiparous Holstein Friesian and their crossbred calves (F1, Japanese Black cattle × Holstein Friesian) and 10 multiparous Holstein Friesian and their Holstein Friesian calves were used to evaluate vitamin E status in periparturient period. Plasma α‐tocopherol (α‐toc) concentrations of the multiparous cows were significantly higher than those of the primiparous cows from 60 days before expected calving to 90 days of lactation (P < 0.05). The multiparous cows had a further decrease in the concentrations of α‐toc and total lipid in plasma to the calving than the primiparous cows. Colostrum α‐toc concentrations in multiparous cows were significantly higher than those of the primiparous cows (P < 0.05). Plasma α‐toc concentrations of calves borne by the multiparous cows were significantly higher than those of the primiparous cows at 5 days of age (P < 0.05). Plasma α‐toc concentrations of calves were highest at 5 and 15 days of age in the calves borne by the multiparous and primiparous cows, respectively, and decreased thereafter till 90 days of age. The higher vitamin E status of multiparous cows over primiparous cows might have reflected nutritional composition in the rations. Their calves afforded higher plasma α‐toc levels after birth because of more α‐toc transfer via placenta and more α‐toc secretion in the colostrums thereafter. Plasma α‐toc concentrations of the calves might have decreased as the calves became dependent upon the solid feed of low vitamin E content.  相似文献   

8.
Organic farming has traditionally given preference to indigenous breeds that are well adapted to local conditions; however, current trends towards increased yields may produce less robust animals with potentially low fertility. The Holstein‐Friesian breed dominates dairy sector, although there is a general concern that these cows may not be well adapted to organic systems. This study aims to evaluate the reproductive performance of organic dairy herds in northern Spain, by comparing organically reared Holstein‐Friesian with their counterparts reared on conventional farms and also with other organically reared breeds and crosses. Reproductive parameters were obtained for individual cows on organic, conventional pasture‐based and conventional zero‐grazing farms. The reproductive performance of Holstein‐Friesian cows was slightly better in organic systems than in pasture‐based conventional systems, but not than in zero‐grazing conventional systems. The comparison of reproductive performance of Holstein‐Friesian from organic and conventional systems and with other organically reared breeds and crosses enabled us to demonstrate that it is not the organic system that constrains the reproductive performance of Holstein‐Friesian, but that the manifestation of oestrus is less marked than in other breeds. Breeding selection considering reproductive traits and appropriate management of oestrous detection would improve the reproductive performance of Holstein‐Friesian cows.  相似文献   

9.

Background

The main objective of this study was to estimate the effect of supplementation with Saccaromyces cerevisiae (SC) (Yea-Sacc® 1026) on milk production, metabolic parameters and the resumption of ovarian activity in early lactation dairy cows.

Methods

The experiment was conducted during 2005/2006 in a commercial tied-house farm with an average of 200 milking Estonian Holstein Friesian cows. The late pregnant multiparous cows (n = 46) were randomly divided into two groups; one group received 10 g yeast culture from two weeks before to 14 weeks after calving. The groups were fed a total mixed ration with silages and concentrates. Milk recording data and blood samples for plasma metabolites were taken. Resumption of luteal activity was determined using milk progesterone (P4) measurements. Uterine bacteriology and ovarian ultrasonography (US) were performed and body condition scores (BCS) and clinical disease occurrences were recorded. For analysis, the statistical software Stata 9.2 and R were used to compute Cox proportional hazard and linear mixed models.

Results

The average milk production per cow did not differ between the groups (32.7 ± 6.4 vs 30.7 ± 5.3 kg/day in the SC and control groups respectively), but the production of milk fat (P < 0.001) and milk protein (P < 0.001) were higher in the SC group. There was no effect of treatment on BCS. The analysis of energy-related metabolites in early lactation showed no significant differences between the groups. In both groups higher levels of β-hydroxybutyrate (BHB) appeared from days 14 to 28 after parturition and the concentration of non-esterfied fatty acid (NEFA) was higher from days 1–7 post partum (PP). According to US and P4 results, all cows in both groups ovulated during the experimental period. The resumption of ovarian activity (first ovulations) and time required for elimination of bacteria from the uterus did not differ between the groups.

Conclusion

Supplementation with SC had an effect on milk protein and fat production, but did not influence the milk yield. No effects on PP metabolic status, bacterial elimination from the uterus nor the resumption of ovarian activity were found.  相似文献   

10.
In 1989, 220 Holstein Friesian cattle (212 heifers and eight bulls) were imported from Minnesota, USA, to form a closed dairy herd in Arab El‐Aoumar, Assiut, Upper Egypt. In November 1996, some abnormal signs such as loss of weight, decreased milk yield, external lymphadenopathy and decreased appetite were observed on this farm. Serological screening by enzyme‐linked immunosorbent assay revealed a seroprevalence of antibodies directed against bovine leukaemia virus (BLV) of 37.7% in cattle under 2 years old and of 72.8% in animals more than 2 years old. Diagnosis was confirmed by the detection of BLV proviral DNA using polymerase chain reaction with primers amplifying a fragment of the env gene. Out of 21 tested leucocyte fractions from individual animals, 15 were positive showing a BLV‐specific amplicon of 444 base pairs. Analysis of the amplicons for restriction fragment length polymorphisms and DNA sequencing results allowed the isolates to be typed. Since this was the first recorded case of enzootic bovine leukosis in Upper Egypt, strict quarantine measures were adopted and all serologically positive animals in the herd were culled.  相似文献   

11.
The objective was to measure the effects of cooling techniques (shade cloth vs. normal roof) on performance and physiology of 16 Friesian crossbred cows (87.5% Holstein Friesian × 12.5% Brahman) located at Sakol Nakhon Livestock Research and Testing Station, Department of Livestock Development, Ministry of Agriculture and Cooperatives (Sakol Nakhon, Thailand). They were divided randomly into two groups of eight. The two groups were used to evaluate the effects of modified roofing (normal roof fitted with woven polypropylene shade cloth) on the subjects' milk yield and reproductive performance under hot humid conditions. Results indicated that the modified roofing offered a more efficient way to minimize heat stress than the normal roof. The difference was sufficient to enable the cows to have a significantly lower mean rectal temperature and respiration rate (38.56°C, 61.97 breaths/min) than that of the cows housed under normal roofing (39.86°C; 85.16 breaths/min). The cows housed under modified roofing produced more milk (P < 0.05) but did not differ significantly in reproductive performance from the cows housed under normal roofing.  相似文献   

12.
Data on 216,428 Danish Red, 798,152 Danish Friesian and 232,953 Danish Jersey cows were used to estimate phenotypic and genetic parameters for actual and production‐corrected survival traits and for milk production. Genetic effects of imported breeds were also estimated. Phenotypic trends in days in milk were similar for Danish Red and Danish Friesian, and showed influences of the milk quota system, whereas Danish Jersey showed a continuous downwards trend. Significant additive and non‐additive effects due to imported breeds were found. Heritabilities differed between breeds, ranging from 0.072 to 0.122 for actual continuous lifetime traits, and from 0.048 to 0.076 for production‐corrected continuous lifetime traits. Binary stayability traits showed lower heritability. Genetic correlations between milk production and actual or production‐corrected days in milk were 0.63 and 0.31 respectively. Genetic correlations between binary stayabilities and continuous lifetime traits were high (>0.78), which indicates that stayabilities can be used as early predictors of the lifetime traits.  相似文献   

13.
[目的] 比较中国荷斯坦奶牛、荷斯坦奶牛和西门塔尔牛乳中常规营养成分含量、矿物质元素含量及脂肪酸含量和组成的差异。[方法] 选取中国荷斯坦奶牛、荷斯坦奶牛和西门塔尔牛各6头,每头奶牛收集200 mL生鲜乳样品,利用乳成分分析仪测定乳中常规营养成分含量,通过原子吸收分光光度计测定乳中矿物质元素含量,应用气相色谱仪测定乳中脂肪酸含量和组成。采用统计学方法对不同品种牛乳中的营养成分含量及脂肪酸含量和组成进行比较。[结果] 中国荷斯坦奶牛生鲜乳中乳脂含量显著(P<0.05)高于荷斯坦奶牛,乳蛋白含量显著(P<0.05)高于荷斯坦奶牛和西门塔尔牛;中国荷斯坦奶牛生鲜乳中乳钙含量显著(P<0.05)高于荷斯坦奶牛,乳锌含量显著(P<0.05)高于荷斯坦奶牛和西门塔尔牛。中国荷斯坦奶牛生鲜乳中豆蔻酸含量显著(P<0.05)低于荷斯坦奶牛,油酸和亚油酸含量显著(P<0.05)高于西门塔尔牛;中国荷斯坦奶牛生鲜乳中饱和脂肪酸含量显著(P<0.05)低于西门塔尔牛,不饱和脂肪酸含量显著(P<0.05)高于西门塔尔牛。[结论] 中国荷斯坦奶牛乳中部分营养成分和矿物质元素含量接近或优于荷斯坦奶牛和西门塔尔牛,脂肪酸含量和组成与荷斯坦奶牛相近,脂肪酸组成优于西门塔尔牛。  相似文献   

14.
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.  相似文献   


15.
In 1989, 220 Holstein Friesian cattle (212 heifers and eight bulls) were imported from Minnesota, USA, to form a closed dairy herd in Arab El-Aoumar, Assiut, Upper Egypt. In November 1996, some abnormal signs such as loss of weight, decreased milk yield, external lymphadenopathy and decreased appetite were observed on this farm. Serological screening by enzyme-linked immunosorbent assay revealed a seroprevalence of antibodies directed against bovine leukaemia virus (BLV) of 37.7% in cattle under 2 years old and of 72.8% in animals more than 2 years old. Diagnosis was confirmed by the detection of BLV proviral DNA using polymerase chain reaction with primers amplifying a fragment of the env gene. Out of 21 tested leucocyte fractions from individual animals, 15 were positive showing a BLV-specific amplicon of 444 base pairs. Analysis of the amplicons for restriction fragment length polymorphisms and DNA sequencing results allowed the isolates to be typed. Since this was the first recorded case of enzootic bovine leukosis in Upper Egypt, strict quarantine measures were adopted and all serologically positive animals in the herd were culled.  相似文献   

16.
Eight periparturient Holstein Friesian cows were examined for plasma tartrate-resistant acid phosphatase (TRAP) activity to assess the degree of bone metabolic activity and to evaluate the association between the change in calcium (Ca) concentration and bone metabolism during the periparturient period. Milk fever occurred in 1 of 8 cows just after parturition. Plasma TRAP activities did not markedly change in 5 of 8 cows during the experimental period. The changing rate of Ca between preparturition and just after parturition was under -20% in 3 of 8 cows, and low TRAP activities were observed in 2 of these 3 cows. This study suggests that cows with a low TRAP activity are at risk of developing milk fever in comparison to cows with high TRAP activity. Temporary increases of parathyroid hormone were observed in 7 cows, but not in the cow with milk fever.  相似文献   

17.
18.
A study was conducted in the Central-western region of Venezuela to investigate the lifetime performances of 7918 Carora and 3501 Holstein cows under two different levels of management (low and high) and covering a period from 1961 to 1995. Traits analysed were: herd life, productive life, number of calvings, lifetime milk yield, days in lactation over all lactations and daily milk yield. In Carora cows born from 1961 to 1986 a decrease in herd life, productive life and number of calvings was observed, whereas cows born between 1971 and 1972 showed the lowest lifetime productive traits. Performances of Holstein cows born in the 1981–1986 period were analysed and all traits decreased during this time period. In low level herds, Holsteins remained longer (98.5 months vs. 83.3 in herd life; 69.5 vs. 54.3 months in productive life) and had higher lifetime yield (20 925 vs. 18 589 kg) than those in high level herds, but daily milk yield was lower (8.4 vs. 11.0 kg/day). All lifetime performances were higher for Carora cows under the high level management: 116.8 vs. 112.1 months of herd life, 81.8 vs. 77.1 months of productive life, 5.8 vs. 5.2 calvings, 1616 vs. 1299 days of lactation, 16 194 vs. 11 912 kg of milk over all lactations and 6.5 vs. 4.6 kg milk/day. Survival estimates for year of birth were more variable in Holsteins than in Carora cows. Management influenced survival in Holsteins only, the low level showing higher values.  相似文献   

19.
In a cross-sectional study of bluetongue virus (BTV) and Mycoplasma bovis (M. bovis) infections, a sample of 572 California dairy cows was tested for the presence of antibodies to answer the question: Is it possible to identify and to assess quantitatively the associations between positive antibody test and production? Serum samples collected from these cows during December 1986 were tested for the presence of antibodies to BTV and M. bovis using the enzyme-linked immunosorbent assay (ELISA). Data on milk production were extracted from individual cow sheets of the California Dairy Herd Improvement Association (DHIA) record-keeping system and interfaced with percentage ELISA results for analysis. Univariate and multivariate statistical analyses, using the X 2 test for categorical variables or Student's t-test for continuous variables and multiple logistic regression respectively, were carried out to evaluate for possible associations between positive antibody tests to each agent and each production variable of interest. Complete data on all variables studied were obtained for 289 (50.5%) cows for M. bovis and 423 (74%) cows for BTV. For cows with complete data on all variables, estimates of the point prevalence of antibodies to BTV and M. bovis were 70.5% and 66.1%, respectively. Results of this study indicated that Guernsey cows were more likely to have a positive BTV test than Holstein cows and that cows in higher lactations were more likely to test positive to BTV ELISA than those in lower lactations (p<0.05). Because all cows except those on one farm were Holstein, our confidence in the effect of breed is limited. The association between lactation number and BTV seropositive test may be an age factor identified earlier in the study. For M. bovis, the results of the analysis indicated that seropositive cows were more likely to produce less milk, on a mature equivalent basis (ORadj=0.96, p=0.034), and that they had less extended 305 day milk production potential (ORadj=0.90, p<0.0001) than seronegative cows.  相似文献   

20.
Prostaglandin (PG) levels in milk samples from healthy and mastitic cows were determined by radioimmunoassay. In composite milk the PG levels were rather high both in healthy and mastitic samples, and the only significant difference was in thromboxane B2 (TXB). In quarter milk samples classified according to the degree of mastitis by use of somatic cell counts, PGE2 was 40, PGF215, and TXB2 44 per cent higher respectively in affected samples. PG levels were in good correlation with somatic cell counts (r=0.63–0.68, p<0.01) and electrical conductivity (r=0.36–0.52, p<0.01), two established criteria for diagnosis of mastitis. PGE2 also correlated with protein, TXB2 with fat content. PGF2 was in a negative correlation with milk yield. The good correlation of PGs with somatic cell counts and electrical conductivity suggests that PGs might be used as markers of mastitic inflammation.  相似文献   

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