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1.
Brown Swiss × Holstein crossbred cows and pure Holstein cows were compared in a designed experiment. All cows were housed in a freestall barn at the experimental station of the federal state of Saxony-Anhalt, Germany, and calved from July 2005 to August 2008. Brown Swiss × Holstein crossbred cows were mated to Holstein AI bulls for first calving and mated to Fleckvieh artificial insemination (AI) bulls for second and third calvings. Pure Holstein cows were consistently mated to Holstein AI bulls. At first calving, Holstein-sired calves from Brown Swiss × Holstein crossbred dams (282 d) had longer gestation length than Holstein-sired calves from Holstein dams (280 d). For second and third calvings, gestation length was significantly longer for Fleckvieh-sired calves from Brown Swiss × Holstein crossbred dams (284 d) than for Holstein-sired calves from Holstein dams (278 d). Holstein-sired calves from Brown Swiss × Holstein crossbred dams (43 kg) and Holstein-sired calves from pure Holstein dams (42 kg) were not significantly different for calf weight at birth for first calving. For second and third calvings, Fleckvieh-sired calves from Brown Swiss × Holstein crossbred dams (50 kg) had significantly heavier calf weight at birth than Holstein-sired calves from pure Holstein dams (44 kg). For calving difficulty and stillbirth, Brown Swiss × Holstein crossbred cows were not different from pure Holstein cows at first calving or at second and third calving. Brown Swiss × Holstein crossbred cows (71 d) were not significantly different from pure Holstein cows (75 d) for days to first breeding during first lactation; however, Brown Swiss × Holstein crossbred cows (81 d) had significantly fewer days to first breeding than pure Holstein cows (89 d) during second lactation, and the crossbred cows (85 d) tended to have fewer days to first breeding than pure Holstein cows (92 d) during third lactation. For days open, Brown Swiss × Holstein crossbred cows were not significantly different than pure Holstein cows during any of the first 3 lactations. For body weight, Brown Swiss × Holstein crossbred cows were significantly heavier than pure Holstein cows during first lactation (621 kg versus 594 kg) and second lactation (678 kg versus 656 kg). Also, Brown Swiss × Holstein crossbred cows (18.20 mm) had significantly more backfat thickness than pure Holstein cows (15.81 mm) during first lactation. Brown Swiss × Holstein crossbred cows (48 cm) had significantly greater chest width than pure Holstein cows (46 cm). Furthermore, Brown Swiss × Holstein crossbred cows had significantly longer front heel walls (5.2 cm versus 5.0 cm), significantly longer rear heel walls (4.2 cm versus 4.0 cm), and significantly more depth of the front heel (4.4 cm vs. 4.1 cm) than pure Holstein cows. This study has shown that F1 of Brown Swiss × Holstein cows are competitive with pure Holstein cows for all traits analyzed here. For fertility, crossbred Brown Swiss × Holstein cows exhibited fewer days to first breeding during second lactation than pure Holstein cows.  相似文献   

2.
This study is part of a larger project whose overall objective was to evaluate the possibilities for genetic improvement of efficiency in Austrian dairy cattle. In 2014, a 1-yr data collection was carried out. Data from 6,519 cows kept on 161 farms were recorded. In addition to routinely recorded data (e.g., milk yield, fertility, disease data), data of novel traits [e.g., body weight (BW), body condition score (BCS), lameness score, body measurements] and individual feeding information and feed quality were recorded on each test-day. The specific objective of this study was to estimate genetic parameters for efficiency (related) traits and to investigate their relationships with BCS and lameness in Austrian Fleckvieh, Brown Swiss, and Holstein cows. The following efficiency (related) traits were considered: energy-corrected milk (ECM), BW, dry matter intake (DMI), energy intake (INEL), ratio of milk output to metabolic BW (ECM/BW0.75), ratio of milk output to DMI (ECM/DMI), and ratio of milk energy output to total energy intake (LE/INEL, LE = energy in milk). For Fleckvieh, the heritability estimates of the efficiency (related) traits ranged from 0.11 for LE/INEL to 0.44 for BW. Heritabilities for BCS and lameness were 0.19 and 0.07, respectively. Repeatabilities were high and ranged from 0.30 for LE/INEL to 0.83 for BW. Heritability estimates were generally lower for Brown Swiss and Holstein, but repeatabilities were in the same range as for Fleckvieh. In all 3 breeds, more-efficient cows were found to have a higher milk yield, lower BW, slightly higher DMI, and lower BCS. Higher efficiency was associated with slightly fewer lameness problems, most likely due to the lower BW (especially in Fleckvieh) and higher DMI of the more-efficient cows. Body weight and BCS were positively correlated. Therefore, when selecting for a lower BW, BCS is required as additional information because, otherwise, no distinction between large animals with low BCS and smaller animals with normal BCS would be possible.  相似文献   

3.
Dairy cow efficiency is increasingly important for future breeding decisions. The efficiency is determined mostly by dry matter intake (DMI). Reducing DMI seems to increase efficiency if milk yield remains the same, but resulting negative energy balance (EB) may cause health problems, especially in early lactation. Objectives of this study were to examine relationships between DMI and liability to diseases. Therefore, cow effects for DMI and EB were correlated with cow effects for 4 disease categories throughout lactation. Disease categories were mastitis, claw and leg diseases, metabolic diseases, and all diseases. In addition, this study presents relative percentages of diseased cows per days in milk (DIM), repeatability, and cow effect correlations for disease categories across DIM. A total of 1,370 German Holstein (GH) and 287 Fleckvieh (FV) primiparous and multiparous dairy cows from 12 dairy research farms in Germany were observed over a period of 2 yr. Farm staff and veterinarians recorded health data. We modeled health and production data with threshold random regression models and linear random regression models. From DIM 2 to 305 average daily DMI was 22.1 kg/d in GH and 20.2 kg/d in FV. Average weekly EB was 2.8 MJ of NEL/d in GH and 0.6 MJ of NEL/d in FV. Most diseases occurred in the first 20 DIM. Multiparous cows were more susceptible to diseases than primiparous cows. Relative percentages of diseased cows were highest for claw and leg diseases, followed by metabolic diseases and mastitis. Repeatability of disease categories and production traits was moderate to high. Cow effect correlations for disease categories were higher for adjacent lactation stages than for more distant lactation stages. Pearson correlation coefficients between cow effects for DMI, as well as EB, and disease categories were estimated from DIM 2 to 305. Almost all correlations were negative in GH, especially in early lactation. In FV, the course of correlations was similar to GH, but correlations were mostly more negative in early lactation. For the first 20 DIM, correlations ranged from ?0.31 to 0.00 in GH and from ?0.42 to ?0.01 in FV. The results illustrate that future breeding for dairy cow efficiency should focus on DMI and EB in early lactation to avoid health problems.  相似文献   

4.
Lameness is a frequent health problem in dairy cows. This preliminary study aimed to detect gait differences between healthy and lame walking cows using 3-dimensional force plates. We examined left–right leg symmetry changes of healthy and lame Holstein dairy cows following claw trimming. Gait scoring (GS) was performed on d −5, 0, 1, and 7 relative to claw trimming. Before the experiment, 5 cows walked normally (initial GS = 1) and 4 cows limped moderately on a hind leg (initial GS = 3). Gait was measured on d −2, −1, 0, 1, and 7 relative to trimming by obtaining ground reaction forces as cows walked repeatedly across 2 parallel 3-dimensional force plates. From the ground reaction forces, stance phase data were derived using computerized procedures. Left–right leg symmetries of entire curves in the 3 force directions were calculated. Effects of lameness and trimming were analyzed in a mixed model, using a low lameness threshold (GS > 1). One week after claw trimming, only one cow was mildly lame. In addition, the symmetries of all 3 dimensions were significantly improved shortly after trimming. Importantly, lameness significantly worsened vertical symmetry. Lame cows walked significantly more slowly than healthy cows. In conclusion, all force symmetries seemed capable of detecting gait responses to claw trimming. Although our results are based on a small number of animals, vertical leg symmetry was affected by lameness.  相似文献   

5.
As part of a cross-sectional study of Norwegian Red Cattle, associations of lameness, lesions at the tarsus, claw shapes, claw lesions, and claw trimming with milk yield were examined. Fifty-five tie-stall herds and 57 free-stall herds were sampled by computerized systematic selection, and 2,665 cows were trimmed and limb and claw disorders recorded. After exclusions, 2,599 cows were included in this study. Monthly recordings of milk were extracted from the Norwegian Dairy Herd Recording System. Most claw lesions were mild (score 1). The prevalence of moderate and severe lesions (score 2 and 3) did not exceed 5% for any of the lesions. Associations with test-day milk yield were identified using regression analyses (Proc Mixed) with repeated measurements within lactation and herd as random effect. Lactation curves were fit to visualize differences in changes in milk yield throughout the lactation. Milk yield was generally higher in cows with lesions at the tarsus, heel-horn erosions, and hemorrhages of the white line and the sole than in cows without these lesions, whereas cows with dermatitis yielded less than cows without dermatitis. Cows in lactation 1 with corkscrewed claws had reduced milk yield, whereas cows in lactations 2 and above had increased milk yield compared with cows without corkscrewed claws in respective lactations. Cows in lactation 1 yielded 0.47 ± 0.15 kg and cows in later lactations yielded 0.51 ± 0.15 kg more milk on test days after claw trimming than they did before when adjusted for days in milk. In this study, where most disorders were mild, the most evident results were higher milk yield in cows with lesions at the tarsus, heel-horn erosions, and hemorrhages of the white line and the sole than in cows without these lesions. Cows yielded more milk after claw trimming than they did before trimming.  相似文献   

6.
《Journal of dairy science》2021,104(10):10905-10920
Lameness is a serious health and welfare issue that can negatively affect the economic performance of cows, especially on pasture-based dairy farms. However, most genetic predictions (GP) of lameness have low accuracy because lameness data are often incomplete as data are collected voluntarily by farmers in countries such as Australia. The objective of this study was to find routinely measured traits that are correlated with lameness and use them in multivariate evaluation models to improve the accuracy of GP for lameness. We used health events and treatments associated with lameness recorded by Australian farmers from 2002 to early 2019. The lameness incidence rates in Holstein and Jersey cows were 3.3% and 4.6%, respectively. We analyzed the records of 36 other traits (milk production, conformation, fertility, and survival traits) to estimate genetic correlations with lameness. The estimated heritability ± standard error (and repeatability ± standard error) for lameness in both Holstein and Jersey breeds were very low: 0.007 ± 0.002 (and 0.029 ± 0.002) and 0.005 ± 0.003 (and 0.027 ± 0.006), respectively, in univariate sire models. For the GP models, we tested including measurements of overall type to prediction models for Holsteins, stature and body length for Jersey, and milk yield and fertility traits for both breeds. The average accuracy of GP, calculated from prediction error variances, were 0.38 and 0.24 for Holstein and Jersey sires, respectively, when estimated using univariate sire models and both increased to 0.43 using multivariate sire models. In conclusion, we found that the accuracy of GP for lameness could be improved by including genetically correlated traits in a multivariate model. However, to further improve the accuracy of predictions of lameness, precise identification and recording incidences of hoof or leg disorder, or large-scale recording of locomotion and claw scores by trained personnel should be considered.  相似文献   

7.
Claw lesions are one of the most important health issues in dairy cattle. Although the frequency of claw lesions depends greatly on herd management, the frequency can be lowered through genetic selection. A genetic evaluation could be developed based on trimming records collected by claw trimmers; however, not all cows present in a herd are usually selected by the breeder to be trimmed. The objectives of this study were to investigate the importance of the preselection of cows for trimming, to account for this preselection, and to estimate genetic parameters of claw health traits. The final data set contained 25,511 trimming records of French Holstein cows. Analyzed claw lesion traits were digital dermatitis, heel horn erosion, interdigital hyperplasia, sole hemorrhage circumscribed, sole hemorrhage diffused, sole ulcer, and white line fissure. All traits were analyzed as binary traits in a multitrait linear animal model. Three scenarios were considered: including only trimmed cows in a 7-trait model (scenario 1); or trimmed cows and contemporary cows not trimmed but present at the time of a visit (considering that nontrimmed cows were healthy) in a 7-trait model (scenario 2); or trimmed cows and contemporary cows not trimmed but present at the time of a visit (considering lesion records for trimmed cows only), in an 8-trait model, including a 0/1 trimming status trait (scenario 3). For scenario 3, heritability estimates ranged from 0.02 to 0.09 on the observed scale. Genetic correlations clearly revealed 2 groups of traits (digital dermatitis, heel horn erosion, and interdigital hyperplasia on the one hand, and sole hemorrhage circumscribed, sole hemorrhage diffused, sole ulcer, and white line fissure on the other hand). Heritabilities on the underlying scale did not vary much depending on the scenario: the effect of the preselection of cows for trimming on the estimation of heritabilities appeared to be negligible. However, including untrimmed cows as healthy caused bias in the estimation of genetic correlations. The use of a trimming status trait to account for preselection appears promising, as it allows consideration of the exhaustive population of cows present at the time a trimmer visited a farm without causing bias in genetic parameters.  相似文献   

8.
Claw disorders are important traits relevant to dairy cattle breeding from an economical and welfare point of view. Selection for reduced claw disorders can be based on hoof trimmer records. Typically, not all cows in a herd are trimmed. Our objectives were to estimate heritabilities and genetic correlations for claw disorders and investigate the effect of selecting cows for trimming. The data set contained 50,238 cows, of which 20,474 cows had at least one claw trimming record, with a total of 29,994 records. Six claw trimmers scored 14 different claw disorders: abscess (AB), corkscrew claw (CC), (inter-)digital dermatitis or heel erosion (DER), double sole (DS), hardship groove (HG), interdigital hyperplasia (IH), interdigital phlegmon (IP), sand crack (SC), super-foul (SF), sole hemorrhage (SH), sole injury (SI), sole ulcer (SU), white line separation (WLS), yellow discoloration of the sole (YD), and a combined claw disorder trait. Frequencies of the claw disorders for trimmed cows ranged from 0.1% (CC, YD, HG) to 23.8% (DER). More than half of the cows scored had at least one claw disorder. Heritability on the observed scale ranged from 0.02 (DS, SH) to 0.14 (IH) and on the underlying scale from 0.05 to 0.43 in trimmed cows. Genetic correlations between laminitis-related claw disorders were moderate to high, and the same was found for hygiene-related claw disorders. The effect of selecting cows for trimming was first investigated by including untrimmed cows in the analyses and assuming they were not affected by claw disorders. Heritabilities on the underlying scale showed only minor changes. Second, different subsets of the data were created based on the percentage of trimmed cows in the herd. Heritabilities for IH, DER, and SU tended to decrease when a higher percentage of cows in the herd were trimmed. Finally, a bivariate model with a claw disorder and the trait “trimming status” was used, but heritabilities were similar. Heritability for trimming status was relatively high (0.09). Genetic correlations of trimming status with claw disorders were generally moderate to high. To conclude, the effect of selecting cows for trimming on the heritability for claw disorders is negligible. Selecting herds with a high fraction of cows being trimmed tended to decrease heritability. Trimming status, as such, is a heritable trait and correlated with claw disorders and is therefore an interesting trait to include in the genetic evaluation.  相似文献   

9.
Lameness causes major financial losses and welfare problems in dairy herds. Prevention of foot lesions may suffice in the majority of lameness cases. The objectives of this longitudinal study were to describe the dynamics and associations between abnormal hind leg conformation, asymmetric claws, lameness, and foot lesions in 122 Danish Holstein heifers from an average of 41 d before first calving until dry off or culling. The cattle were housed either in a free-stall system with cubicles or in deep-bedded straw yard. The claws of all cattle were examined on up to 5 occasions. The associations between foot lesions, lameness, symmetry of the claws, shape of the dorsal toe-wall, and the conformation of the hind legs were examined statistically using mixed models. A large proportion (81%) of the heifers had cow-hocked conformation, with wide-based stance, hocks together, and lateral rotation of the foot before calving, and 25% of the heifers had locomotion scores above 2, indicating signs of lameness, before calving. Our results indicate that lameness, abnormal conformation, and lesions acquired precalving persist throughout the first lactation. Thinner cows were more cow-hocked, and cow-hocked cows had a higher frequency of sole hemorrhages. Increased severity of white line lesion was associated with greater claw asymmetry. More severe lameness and sole hemorrhages were found in symmetric claws.  相似文献   

10.
Results of a producer survey regarding crossbreeding on US dairy farms   总被引:2,自引:0,他引:2  
Comprehensive surveys were sent to 528 US dairy producers who are currently practicing crossbreeding in their herds. Fifty usable surveys were returned, and the resulting data included qualitative responses regarding facilities, milk recording plans, milk pricing, crossbreeding goals, breed selection, advantages, disadvantages, and future plans. Quantitative variables included producer scores on a 1 to 5 scale for questions regarding ability to fit into the free stalls and milking parlor, milk volume, component percentages, involuntary culling rate, conception rate, calving difficulty, calf mortality, and prices for breeding stock, cull cows, market steers, and bull calves. The most common first generation crosses involved Jersey and Brown Swiss bulls mated to Holstein cows, and backcrosses to one of these parental breeds were most common in the next generation. Producers who responded to this survey desired, and indicated that they achieved, improvements in fertility, calving ease, longevity, and component percentages through crossbreeding. Respondents indicated that crosses involving the Jersey and Brown Swiss breeds had a clear advantage in longevity relative to purebred Holsteins, and conception rates for crosses of Jersey or Brown Swiss sires on Holstein cows were similar to the (high) conception rates typically achieved in purebred Jersey matings. Respondents also indicated that milk composition was improved in the crossbred cattle, but producers cited some difficulties in marketing crossbred breeding stock and bull calves, and noted that the lack of uniformity within the milking herd created management challenges. Based on results of this survey, it appears that crossbreeding can improve the health, fertility, longevity, and profitability of commercial dairy cattle. However, further research is needed regarding specific heterosis estimates for functional traits in crosses involving each of the major dairy breeds, and improvements are needed in systems for recording the ancestry and breed composition of crossbred animals.  相似文献   

11.
Impaired claw health is one of the major problems causing production loss and reduced animal welfare in dairy cattle. In response, the Dutch Animal Health Service (GD) Ltd. initiated this study, in which claws of lactating and near-term cows and heifers in 430 herds were trimmed by hoof trimmers and the health status of the rear claws recorded. Only herds with >75% of the animals having feet trimmed were considered, resulting in records on 21,611 animals. Eight claw disorders were scored: digital dermatitis (DD), interdigital dermatitis/heel horn erosions (IDHE), sole hemorrhage (SH), chronic laminitis (CL), sole ulcer (SU), white line disease (WLD), interdigital hyperplasia (HYP), and interdigital phlegmona (IP). The prevalence varied from 0.6% (IP) to 39.9% (SH). More than 70% of the animals had at least one claw disorder. Conformation traits and locomotion were recorded once during the animal's first lactation by trained classifiers of the Royal Dutch Cattle Syndicate and completely independent of the moment of claw trimming. Heritabilities were estimated using a sire model, and ranged from <0.01 (IP) to 0.10 (DD and HYP). Genetic correlations of incidences of claw disorders with locomotion were variable, ranging from 0.13 (SH) to −0.91 (CL). Genetic correlations with the rear leg conformation traits were lower, ranging from 0.04 (ID with rear leg side view) to −0.69 (IP with rear leg rear view).  相似文献   

12.
The objective of this study was to investigate whether cows diagnosed with claw horn lesions during routine claw trimming had an altered milk fat percentage on test days preceding the diagnosis, compared with cows without such lesions. Data included date of trimming, cow number, type, and location of claw lesions recorded by a professional claw trimmer during routine trimming sessions on 11 commercial dairy farms, and monthly test-day data. Recordings from 4,381 cows were included in the analysis. Three hundred seventy-two (8.5%) cows were diagnosed with at least one claw lesion. One hundred ninety-five (4.4%) cows were classified as cases of laminitis and 169 cows (3.9%) were classified as cases of infectious claw diseases. Average test-day milk fat percentage was estimated from monthly test-day data using a mixed model with a random farm effect and a marginal effect for repeated measurements. Estimated milk fat percentage of cows classified as cases of laminitis on the day of claw trimming was 0.17 and 0.22% less than that of cows with either no claw lesion or those with an infectious claw disease, on test days occurring 2 and 5 mo before claw trimming, respectively. To the best of our knowledge, decreased test-day milk fat percentage in dairy cows diagnosed with claw horn lesions has not been described. Because decreased milk fat and claw horn lesions have both been associated with subacute ruminal acidosis, it is plausible that subacute ruminal acidosis played a role in the association we found. A prospective study with a greater frequency of claw examinations would be necessary to help clarify these associations. Our findings indicate that test-day milk fat might be useful as a tool for monitoring cows and farms at risk for claw horn lesions.  相似文献   

13.
Intersucking, i.e., cattle sucking the udder of heifers or cows, is a frequent problem in dairy herds and may lead to udder damage, mastitis, milk loss, and culling of breeding animals. Using epidemiological methods, we conducted an observational cross-sectional study to investigate risk factors for intersucking in Swiss dairy cows. We asked 114 randomly selected dairy farmers about a broad spectrum of environmental factors possibly associated with intersucking, such as housing conditions, management, and feeding of calves, heifers, and cows. Thirty of the 114 farms were confronted with intersucking in cows. The mean proportion of intersucking cows per farm was 1.6%. From a total of 3077 cows (Swiss Brown Cattle, Simmental, and Holstein Friesian) we recorded 49 cows that had performed or were currently intersucking. In 69% of these cows, intersucking had been observed as heifers. Using path analysis and multivariable stepwise backward logistic and linear regression analyses, we revealed that the most important risk factor for intersucking cows was the presence of intersucking heifers on a farm (odds ratio = 7.8). The results suggest that intersucking in cows is the continuation of a habit that was already established in a cow's subadult life. This emphasizes the importance of looking not only at the animal's current environmental situation but also considering its entire life history for the prevention of behavioral problems.  相似文献   

14.
The first objective of this study was to compare the productive and reproductive performance of Holstein-Friesian (CH HF), Fleckvieh (CH FV), and Brown Swiss (CH BS) cows of Swiss origin with New Zealand Holstein-Friesian (NZ HF) cows in pasture-based compact-calving systems; NZ HF cows were chosen as the reference population for such grazing systems. The second objective was to analyze the relationships within and between breeds regarding reproductive performance, milk yield, and body condition score (BCS) dynamics. On 15 commercial Swiss farms, NZ HF cows were paired with Swiss cows over 3 yr. Overall, the study involved 259 complete lactations from 134 cows: 131 from 58 NZ HF, 40 from 24 CH HF, 43 from 27 CH FV, and 45 from 25 CH BS cows. All production parameters were affected by cow breed. Milk and energy-corrected milk yield over 270 d of lactation differed by 1,000 kg between the 2 extreme groups; CH HF having the highest yield and CH BS the lowest. The NZ HF cows had the greatest milk fat and protein concentrations over the lactation and exhibited the highest lactation persistency. Body weight differed by 90 kg between extreme groups; NZ HF and CH BS being the lightest and CH HF and CH FV the heaviest. As a result, the 2 HF strains achieved the highest milk production efficiency (270-d energy-corrected milk/body weight0.75). Although less efficient at milk production, CH FV had a high 21-d submission rate (86%) and a high conception rate within 2 inseminations (89%), achieving high pregnancy rates within the first 3 and 6 wk of the breeding period (65 and 81%, respectively). Conversely, poorer reproductive performance was recorded for CH HF cows, with NZ HF and CH BS being intermediate. Both BCS at nadir and at 100 d postpartum had a positive effect on the 6-wk pregnancy rate, even when breed was included in the model. The BCS at 100 d of lactation also positively affected first service conception rate. In conclusion, despite their high milk production efficiency, even in low-input systems, CH HF were not suited to pasture-based seasonal-calving production systems due to poor reproductive performance. On the contrary, CH FV fulfilled the compact-calving reproduction objectives and deserve further consideration in seasonal calving systems, despite their lower milk production potential.  相似文献   

15.
Thin soles and resulting lameness are often associated with increased culling rates in large dairy operations. The moisture content of the sole horn may cause the horn to be softer, thus predisposing it to an increased rate of wear. For that reason, the first objective of this study was to determine the moisture content of the sole horn of thin-soled cows. The second objective was to document physical changes of the claw associated with thin soles. Twenty-six adult Holstein cows showing signs of thin soles, and 16 normal cows were used in the study. Selection criteria for thin-soled cows included a dorsal wall length of less than 7.5 cm and the following clinical signs: painful gait, arched back, and specific leg lameness. Sixteen normal adult cows with dorsal wall length in excess of 7.5 cm were randomly selected. For thin-soled cows, the moisture contents of sole horn were 37.1 +/- 0.7% for front claws and 40.5 +/- 0.7% for rear claws. These values were significantly different from each other. Moisture contents of sole horn from normal cows were 31.08 +/- 0.93% for front claws and 33.1 +/- 0.9% for rear claws, which were significantly different from each other and different from thin-soled cows. Rear claws had higher moisture contents than front claws. Mean sole horn thickness was 4.23 +/- 0.18 mm for the rear lateral claws and 5.15 +/- 0.18 mm for the rear medial claws. The average dorsal wall lengths were 66.8 +/- 3.94 mm for rear lateral claws and 69.1 +/- 7.25 mm for rear medial claws. Thirty percent of rear feet with thin soles had pathological claw horn lesions including sole/white line separation (72%) and sole ulcers (28%). Of the affected claws, 13% had more than one lesion. Seventy-seven percent of claw lesions occurred in the lateral claw.  相似文献   

16.
The objective of this study was to investigate the association of some herd-level factors with the prevalence of lameness in 53 high-production groups of Holstein cows housed on 50 commercial dairy farms having freestall barns in Minnesota. Cows in the high-production group (n = 5,626) were scored for locomotion (score of 1 to 5, where 1 = normal and 5 = severely lame) to estimate prevalence of lameness (locomotion score ≥3) in the group. Herd-level variables were used to explain the variation in prevalence among groups. Among the variables tested, herd size, pen space per cow, type and size of milking parlor, total mixed ration content of crude protein and neutral detergent fiber, feeding frequency, linear feedbunk space per cow, type of feed barrier, and use of footbath did not show any association with the prevalence of lameness in the univariate analysis screening test and were not included in the multivariate model. Pen stocking density (cows per 100 stalls), total daily distance between pen and milking parlor, number of cows per full-time employee equivalent, cud chewing index, and pen type were eliminated from the multivariate model in the backwards stepwise procedure. Daily time away from the pen for milking was positively associated with the prevalence of lameness, whereas cow comfort quotient was negatively associated with prevalence of lameness. Prevalence of lameness was greater when farms performed hoof trimming only when the manager decided cows needed it because of hoof overgrowth or lameness compared with farms on which the feet of all cows were trimmed on a maintenance schedule once or twice annually. Brisket board height of more than 15.24 cm and presence of the area behind the brisket board filled with concrete were associated with greater prevalence of lameness. Most of these herd-level factors could be managed to reduce lameness prevalence in commercial dairy farms.  相似文献   

17.
A 15-wk 2 x 3 factorial trial in a university dairy herd compared the effects of two alley surfaces and three free-stall beds on indices of lameness. Alley surfaces were grooved concrete (Ct) or 1.9-cm-thick interlocking rubber mats (R). Stalls were deep sand (S), rubber mattresses (M), or concrete (C). Mattress and concrete stalls were bedded with sawdust. At wk 1 and 15, the hind claws and hocks of 120 primi- (n = 69) and multiparous (n = 51) cows were scored for lesions and three claw measurements (dorsal wall length, heel depth, and toe angle) were recorded. Rates of lateral and medial claw growth and wear were calculated by measuring the migration of a reference mark away from the coronet. Digital photographs of claw surfaces were used to rescore claw lesions. Clinical lameness was evaluated by assigning a locomotion score from 1 to 4 to each cow during wk 1, 5, 10, and 14. Digital dermatitis (present/not present) and interdigital dermatitis (mild, moderate, or severe) were recorded at wk 15. The number of days that cows spent in a hospital barn was recorded. Before assignment, cows were professionally foot trimmed, sorted by initial claw lesion score, and then randomized in consecutive blocks of three to stall treatments. Photograph scores were highly repeatable. Nonparametric statistical techniques were used for analyses of rank data. Claw lesion score increased significantly for all treatment groups except RC and RS; however, when early lactation cows were excluded, no differences were found between treatment groups. Hock scores increased significantly more for cows in CtC than in CtS or RS. Significantly more animals from RC spent more than 10 d in the hospital pen compared with RM and RS. Groups did not significantly differ for clinical lameness. Cows in RS and RC had significantly lower rates for lateral claw net growth than those in CtM. Having moderate or severe interdigital dermatitis at wk 15 was associated with greater increases in claw lesion score and more treatments for digital dermatitis. All claw measurements were correlated; however, toe angle was most strongly correlated with the other two. In this experiment, stall and alley configurations did not lead to significant differences in several indices of lameness.  相似文献   

18.
The primary aim of this study was to estimate heritabilities for different types of claw and foot disorders and the genetic relationship of disorders with milk yield and selected conformation traits by applying logistic models in Holstein dairy cattle. The study included data from 5634 Holstein cows kept on large-scale dairy farms in Eastern Germany. Dichotomous response variables were the presence or absence of the disorder in 2003. Cows that were present in herds for <6 wk in 2003 were excluded from the analysis. Incidences, disregarding repeated measurements, for digital dermatitis (DD), sole ulceration (SU), wall disorder (WD), and interdigital hyperplasia (IH) in rear legs were 13.2, 16.1, 9.6, and 6.3%, respectively. The herd effect was highly significant for all disorders. Incidences increased with increasing parities for SU and WD, but were highest among heifers for DD. High milk yield at the first 2 test d after calving was associated with a greater risk for claw and foot disorders in the same lactation. Estimates of heritability were 0.073 for DD, 0.086 for SU, 0.104 for WD, and 0.115 for IH. Genetically, health problems appear to occur in clusters (i.e., a cow showing one disease has an increased genetic risk of showing another claw disease). This phenomenon was also observed between claw and foot disorders and the somatic cell score. Genetic correlations between milk yield in early lactation and disorders were 0.240 for DD, 0.057 for SU, 0.270 for WD, and 0.336 for IH, indicating a physiological antagonism. Correlations between breeding values for claw and foot disorders of bulls and official breeding values for functional type traits were mostly favorable. Routine recording of claw data will offer a new chance to improve claw health within the population as was elaborated by different scenarios applying selection index procedures.  相似文献   

19.
Lameness is a persistent and underreported health and welfare problem in the dairy industry, resulting in reduced cow performance and profitability as well as early culling. The study objectives were (1) to quantify the impact of the first instance of lameness, at different stages of lactation, on production and economic performance, and (2) to further quantify the impacts of the first instance of lameness when only cows that remain in the herd for at least 100 d in milk (DIM) and those that remain for 305 DIM are included in the analysis. A retrospective longitudinal study was conducted using pre-existing data from animal health records and Dairy Herd Improvement Association records. Data were edited based on selected inclusion criteria, yielding a data set containing records from 15,159 first-lactation Holstein cows from 120 herds with year of first calving between 2003 and 2014. Lame cows were assigned to 1 of 4 groups based on when in the lactation the first event of lameness occurred: transition (1–21 DIM), early lactation (22–100 DIM), mid-lactation (101–200 DIM), or late lactation (201+ DIM). Mid- and late-lactation lame cows were also stratified by cumulative milk yield before the lameness event. Healthy cows (i.e., no recorded lameness event) were randomly assigned for each lactation stage, with mid-lactation healthy and late-lactation healthy cows similarly stratified. Production performance (cumulative milk, fat, and protein yield) and economic performance [milk value, margin over feed cost (MOFC), and gross profit] were analyzed using a mixed model with herd as a random effect. Cumulative milk yields were 811 to 1,290 kg lower for lame cows than for healthy cows, with milk component yields undergoing similar reductions. Reductions in milk yield contributed to losses in milk value (?Can$527 to ?Can$1,083; ?US$419 to ?US$862) and MOFC (?Can$510 to ?Can$774; ?US$406 to ?US$616). Higher losses were reported using gross profit (?Can$753 to ?Can$1,052; ?US$599 to ?US$837), which includes all lameness-related costs. Production and performance losses were smaller when 100 DIM and 305 DIM thresholds were applied (i.e., exclusion of cows culled before 100 and 305 DIM, respectively), however, mid- and late-lactation lame cows maintained high levels of significant losses for all 6 variables analyzed. Lameness also led to higher levels of culling, masking losses for transition and early-lactation lame cows in the 305-DIM analysis. Increasing producer understanding of the costs associated with lameness not only serves to provide insight to producers for more informed culling decisions, but may also help producers weigh the costs of adopting new methods and technologies targeted at reducing on-farm lameness.  相似文献   

20.
The objectives of the study were to compare the ovarian activity of Holstein-Friesian (CH HF), Fleckvieh (CH FV) and Brown Swiss (CH BS) dairy cows of Swiss origin with that of Holstein-Friesian (NZ HF) dairy cows of New Zealand origin, the latter being used as a reference for reproductive performance in pasture-based seasonal calving systems. Fifty, second-lactation NZ HF cows were each paired with a second-lactation Swiss cow (17, 15 and 18 CH HF, CH FV and CH BS respectively) in 13 pasture-based, seasonal-calving commercial dairy farms in Switzerland. Ovarian activity was monitored by progesterone profiling from calving to first breeding service. CH BS cows produced less energy-corrected milk (mean 22·8 kg/d) than the other breeds (26·0-26·5 kg/d) during the first 100 d of lactation. CH HF cows had the lowest body condition score (BCS) at calving and the greatest BCS loss from calving to 30 d post partum. Commencement of luteal activity (CLA) was later for NZ HF than for CH FV (51·5 v. 29·2 d; P <0·01), with CH HF and CH BS intermediate (43 d). On average, NZ HF and CH HF cows had one oestrous cycle before the onset of the seasonal breeding period; this was less (P<0·01) than either CH FV (1·7) or CH BS (1·6). There was a low prevalence of luteal persistency (3%) among the studied cows. First and second oestrous cycle inter-ovulatory intervals did not differ between breeds (20·5-22·6 d). The luteal phase length of CH BS during the second cycle was shorter (10·6 d) than that of the other breeds (13·8-16·0 d), but the inter-luteal interval was longer (9·8 d v. 7·0-8·0 d). The results suggest that the Swiss breeds investigated have a shorter interval from calving to CLA than NZ HF cows.  相似文献   

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