Calving performance in damish breeds of dual purpose cattle

In the last decade much information has already been obtained on calving performance, especially by means of biometrics. The present publication gives additional data on this subject.Data from 1 484 first calvings in two dual purpose Danish breeds of cattle (Red Danish and Black Pied Danish) were analysed. The original data from the progeny testing stations, and calving performance was scored on a scale: 1 = normal; 2 = slightly difficult; 3 = very difficult. The age of the helfers was on average 29.6 months.Heritability for the scored calving performance was calculated in two different ways, the results ranging from 0.13 to 0.32 for Red Danish and from 0.10 to 0.18 for Black Pied Danish.The phenotypic correlation between calving difficulty score and weight of calf was found to be between 0.18 and 0.26 for both breeds.The levels of the genetic correlations indicate that in the Red Danish breed the bigger heifers have the easiest calvings. For the Black Pled Breed the smallest heifers have the easiet calvings. For both breeds heifers with wider hips and thurls have more difficult calvings.     

Comparison of sow farrowing characteristics between a Chinese breed and three French breeds

Sow farrowing characteristics, including litter size, stillbirth, kinetics of births and piglet weight traits, were compared in 4 populations: Meishan (MS), Large White (LW), Duroc × Large White (DU × LW) and Laconie (LA). The kinetics of births was characterised by farrowing duration (FD), birth interval (BI), and farrowing irregularity, estimated by the standard deviation of BI (SDBI). The within-litter distribution of piglet birth weights was described by different traits including the mean (MBW) and standard deviation (SDBW) of birth weight. Additional characteristics of the sow were also analysed: weight at farrowing (SWF), gestation length (GEST), and birth assistance (BA). The data set included 47 MS, 605 LW, 55 DU × LW and 160 LA litters. For analyses, multivariate methods were used, including principal component analyses (PCA) and multiple factorial analyses (MFA). These methods allowed the relative importance of between-breed and within-breed variability of the correlation structure to be estimated and the homogeneity between populations (by comparison of the 4 breed correlation structures) to be investigated. Though most of the variability was observed within-breed (97%), between-breed variation appeared to be highly significant (P < 0.0001). This variation was essentially due to the Meishan breed departing from others, because of the lower weight at farrowing and, to a lesser extent, to the lower number of stillbirths and lower piglet mean and standard deviation in birth weight. Litter size did not contribute much to the variability between breeds. The rather strong correlations related to between-breed structures (r > 0.70) indicated that the correlation pattern was similar among breeds. Stillbirth was independent from litter size and appeared as closely associated with farrowing duration in the French breeds.     

Relationship between leptin content, metabolic hormones and fat deposition in three beef cattle breeds

The aim of the study was to determine if cattle breeds differing in their carcass characteristics also differ in the profiles of their leptin and metabolic hormones. Three breeds, Belgian Blue (BB) (n = 12), Limousin (L) (n = 12) and Aberdeen Angus (AA) (n = 12) with varying ability to deposit fat and protein were compared. Blood, muscle and subcutaneous (SC) adipose tissue were sampled. Animal performance, carcass and meat characteristics were determined as well as plasma leptin concentration, leptin gene expression in SC adipose tissue, leptin-receptor gene expression in SC adipose tissue and plasma concentration of insulin, tri-iodothyronin (T3), thyroxin (T4) and cortisol. The BB bulls showed the lowest values of leptin gene expression (P < 0.05). Values of plasma leptin concentration and of leptin-receptor gene expression tended to be lower in BB than in the other breeds. For a similar amount of adipose tissue (after normalisation), BB bulls showed a higher ratio of plasma leptin (P < 0.05), whereas normalised leptin gene and leptin-receptor gene expressions did not significantly differ between breeds. Belgian Blue bulls also differed in their metabolic hormone profile, tending to show lower values of insulin, T3 and T4 than the two other breeds. Cortisol levels were significantly lower (P < 0.05) in BB than in L and AA animals.     

Effects of stair-step nutrition and trace mineral supplementation on attainment of puberty in beef heifers of three sire breeds.

A study was conducted to evaluate the influence of nutrition and sire breed on age at puberty and first lactation milk yield in crossbred beef heifers. After weaning, 208 heifers sired by Hereford, Limousin, or Piedmontese bulls were assigned to either a control (CG) or stair-step gain (SSG) dietary regimen plus a mineral supplement with or without Cu, Zn, and Mn top-dressed onto the feed. Heifers on the SSG regimen were fed a diet intended to supply energy to support gains at a rate of 120% of the CG diet for 55 d and then were switched to a diet formulated to produce an ADG at 70% of the rate of the CG diet for 84 d. They then switched back to the 120% diet for the last 30 d before breeding. Total weight gain and overall rate of gain did not differ among dietary treatments. Hereford- and Limousin-sired heifers gained at similar rates, and Piedmontese-sired heifers gained an average of .10 kg/d slower than the other two sire breed groups. During one period, Piedmontese-sired heifers on the CG diet gained .19 kg/d faster ( P < . 01) when supplemented with mineral than when not. During that same period, there was no influence of mineral supplementation on weight gains for Hereford- or Piedmontese-sired heifers on the high SSG diet, but Limousin-sired heifers tended (P = .07) to gain faster (1.00 vs .85 kg/d) when supplemented with Cu, Zn, and Mn than when not. Piedmontese-sired heifers reached puberty at the earliest age (P = .03), followed by Hereford- and then Limousin-sired heifers. There were no treatment effects on milk yield at an average of 70 d of lactation. However, at approximately 120 d of lactation, Piedmontese-sired heifers were producing less milk (P < .05) than Limousin- but not Hereford-sired heifers. Hereford-sired heifers had lower (P < .05) plasma Cu concentrations than Piedmontese-sired heifers. There were no treatment effects on plasma Zn concentrations. Heifers sired by bulls of breeds that differ in potential muscularity differed in growth, reproduction, milk yield, and plasma mineral concentrations, but dietary treatments resulted in little to no differences in these variables.     

气温对不同品种肉牛精液品质的影响

为了研究气温对不同品种肉牛精液品质的影响 ,统计分析了 2 0 0 2年、2 0 0 3年 15月的气温及两品种肉牛精液品质的变化。结果表明 :两品种的射精量同期相比 ,差异不显著 (P >0 0 5 ) ;同年同期两品种的精子总数相比 ,差异均为极显著 (P<0 0 1) ;两年来 ,两品种精子总数下降值同期相比 ,12月份差异不显著 ,3 5月份差异极显著 (P <0 0 1) ;两年来 ,两品种的原精活力分别同期相比 ,结果一致 ,1月、5月差异不显著 (P >0 0 5 ) ,2月、3月差异显著 (P <0 0 5 ) ,4月份差异极显著 (P<0 0 1) ;2 0 0 2年 ,两品种原精活力同期相比 ,1月份差异显著 (P <0 0 5 ) ,2 5月份差异不显著 (P >0 0 5 ) ;2 0 0 3年两品种原精活力同期相比 ,14月差异不显著 (P >0 0 5 ) ,5月份差异显著 (P <0 0 5 ) ;2 0 0 2年两品种冻精活力同期相比 ,1月份差异显著 (P <0 0 5 ) ,2 5月份差异不显著 (P >0 0 5 ) ;2 0 0 3年两品种冻精活力同期相比 ,14月份差异不显著 (P >0 0 5 ) ,5月份差异显著 (P <0 0 5 )。     

Hind limb skeletal lesions in 12-month-old bulls of beef breeds

In the present study, right hind limb bones from 46 12-month-old bulls with no clinical signs were examined to identify and describe lesions that could predispose the stifle and tarsal joints to osteoarthritis. The bulls came from a performance testing station and were slaughtered due to a low index at the end of the testing period 1996-97. Differences in frequency of lesions among breeds as well as the relationship between lesions and growth rate were evaluated. Forty-five (97.8%) of the 46 bulls had lesions in the joints and/or growth plates. Prevalence of lesions was 100% in the Charolais (22/22), the Hereford (8/8), and the Limousin (4/4) breeds, and 85.7% (6/7) in the Simmental breed. The stifle was affected in 37, the tarsus in 33, and the growth plates in 34, of the 46 bulls. Lesions found in the stifle joint were: osteochondrosis of the articular-epiphysical cartilage complex (AECC) (25), subchondral bone cyst of the distal femur (1), fragmentation of the medial intercondylar eminence of the tibia (20), cleft in the distal part of the patellar groove (28), and an avulsion fracture of the lateral condyle together with a partial tear of the cranial cruciate ligament (1). Lesions found in the tarsal joint were: osteochondrosis of the AECC (23), ulcerative lesions of the articular cartilage of the talus (25), and fracture of the medial malleolus (4). Twenty-eight bulls had lesions of osteochondrosis at the AECC and 37 at the growth plates. When osteochondrosis at the AECC and thickening of the growth plates were combined, 44 of the 46 bulls had at least one lesion at the AECC and/or the growth plate. Prevalence of bulls with at least one lesion was similar between breeds, but the number of lesions per bull was significantly higher in Charolais followed by Simmental, Hereford, and Limousin. Number of lesions per bull was significantly correlated with daily weight gain, carcase weight, and the width of the proximal tibial epiphysis. Lesions were statistically independent, indicating that local biomechanical factors within the joints are important in the pathogenesis. In conclusion, we suggest that the high incidence of hind limb osteoarthritis reported in the Swedish beef bull population can be explained by the high prevalence of skeletal lesions found in the present material. The lesions appeared to be related to high growth rate and to the breed.     

不同品种肉牛杂交F1育肥效果对比试验

选择不同杂交品种肉牛和本地黄牛共40头,即西黄牛(西门塔尔牛×本地黄牛)、夏黄牛(夏洛来牛×本地黄牛)、皮黄牛(皮埃蒙特牛×本地黄牛)的F1和黄牛(本地黄牛)公牛各10头,进行了100 d育肥饲养比较试验.结果表明:夏黄牛(1 334 g)、西黄牛(1 309 g)和皮黄牛(1 121 g)育肥期平均日增重均显著高于黄牛(827 g,P<0.05),西黄牛和夏黄牛平均日增重也分别显著高于皮黄牛,而西黄牛和夏黄牛之间没有显著差异(P>0.05).夏黄牛(61.3%)、西黄牛(60.8%)和皮黄牛(58.2%)屠宰率均显著高于黄牛(51.2%,P<0.05),杂交组肉牛屠宰率间没有显著差异(P>0.05);3个杂交组肉牛净肉率均显著高于黄牛(P<0.05),虽然西黄牛和夏黄牛净肉率间较差异不显著(P>0.05),但却分别显著高于皮黄牛(P<0.05).3个杂交组牛肉眼肌面积均比黄牛大,而杂交组之间没有显著差异(P>0.05);西黄牛和皮黄牛牛肉大理石纹状度较好,夏黄牛肉嫩度不如西黄牛、皮黄牛和黄牛.4个组之间牛肉的pH和灰分没有差异(P>0.05),但是黄牛肉蛋白质含量显著高于3个杂交组牛(P<0.05),皮黄牛肉脂肪含量明显低于其他3组牛.     

Genetic analysis of three South African horse breeds

Genetic variability at 7 blood-group and 10 biochemical genetic loci was examined in 3 South African horse breeds, the Nooitgedacht, Boerperd and Basuto Pony. Observed heterozygosity for these breeds was intermediate for domestic horses, with the highest heterozygosity in the Boerperd and the lowest in the Basuto Pony. The 3 breeds show greater genetic similarity to each other than to other domestic horse breeds. Compared to other breeds, the South African breeds show greater genetic similarity to breeds such as the Thoroughbred, Holstein, Trakehner and Hanovarian and also to North American breeds such as the Saddlebred, Standardbred and Morgan Horse.     

Performance of three tropical hair sheep breeds.

The performance of three hair sheep breeds (Brazilian Somali, Morada Nova, and Santa Ines) was evaluated in the production environment of northeastern Brazil. Data from a total of 524 lambs sired by 21 rams and out of 190 ewes were analyzed. These data were collected from 1980 to 1983 at Sobral, Brazil from an experiment designed to compare performance of the three breeds. The traits included weights of lambs at birth, weaning, 8 mo, 10 mo, and yearling ages and ewe characters of weight at lambing (EWT), total lamb weight born (LWB), total lamb weight weaned (LWW), and prolificacy rate (PR). Differences (P < .01) among breeds were found for all characters. The Brazilian Somali, the smallest and slowest-gaining breed, was less sensitive to yearly variation than were the other breeds. The Santa Ines, the largest and fastest-gaining breed, was superior in LWB and LWW per ewe lambing. Averaged over the 4-yr period, the Morada Nova had the highest PR (1.82), and the Brazilian Somali and Santa Ines had similar PR (1.39 and 1.31, respectively). Environmental effects on PR due to yearly rainfall quantity and distribution pattern influenced lamb growth up to weaning and ewe reproduction performance. Breed x year (P < .05) interaction effects on PR were largely attributable to the Somali breed's exhibiting higher PR than the Santa Ines and Morada Nova breeds during the relatively wet years of 1981 and 1982.     

The blood composition of different breeds of bulls undergoing beef performance tests

Blood samples taken on three occasions from each of 66 bulls undergoing beef performance tests were analysed for packed cell volume, blood glucose, haemoglobin, serum albumin, urea nitrogen, total protein, inorganic phosphate, Ca, Ca, Mg, K, Na, Cu, Fe and total iron binding capacity. The bulls were individually fed and situated at two centres, one accommodating Lincoln-Red, Devon and Sussex breeds and the other, Hereford. Significant differences between the Lincoln-Red, Devon and Sussex breeds were observed in concentrations of glucose, urea nitrogen, total iron binding capacity (P less than 0.001), Ca (P less than 0.01), Na and Cu (P less than 0.05). There were no significant correlations between the growth rates of individual bulls and their blood composition.     

Seroprevalence of neosporosis in beef and dairy cattle breeds in Northeast Hungary

In order to assess the seroprevalence of bovine neosporosis with indirect fluorescent antibody test (IFAT), blood samples were collected randomly from 1063 beef and dairy cattle belonging to 12 different breeds in Northeast Hungary. Antibodies to Neospora caninum were detected in 27 (2.5%) of the animals, kept on 19 of the 42 settlements included in this survey. Since samples were collected on 50 farms, herd prevalence amounted to 38%. The percentage of cattle with seroconversion increased with age, suggesting a postnatal source of infection. The highest rate of positivity was detected in Aberdeen Angus (3.3%) and Holstein-Friesian cows (3.2%), and the lowest in Limousine (0.9%), but no breed predisposition was statistically substantiated. Neosporosis was more prevalent in dairy (3.4%) than in beef (1.9%) cattle, although the difference was not significant. Only three out of the seropositive cows, all of them Holstein-Friesians, had a history of abortion.     

How the surveillance system may bias the results of analytical epidemiological studies on BSE: prevalence among dairy versus beef suckler cattle breeds in France

Until recently, epidemiological studies on Bovine Spongiform Encephalopathy (BSE) were based on Mandatory Reporting Systems (MRS) of clinically suspect bovines only, but rapid diagnostic tests were validated in 1999 and are used for targeted surveillance in Switzerland, France and other countries, as a complementary and secondary tool. Data on 30491 cattle issued from a French pilot program targeted at cattle having died on the farm, subjected to euthanasia or sent for emergency slaughter, did not show any significant difference in BSE risk between dairy and beef suckler breeds. The data also revealed that part of the clinical cases of BSE escaped the MRS, which permitted to detect more dairy than beef suckler affected cattle compared to the targeted surveillance in the same period (from August to December 2000) and region (Bretagne, Pays de la Loire and Basse Normandie regions). Analyzing together the data of the targeted surveillance and mandatory reporting system programs with a non-conditional logistic regression, we found that the odds of a dead cow being a BSE case among all dead cattle was 3.2 times higher for dairy breeds compared to beef suckler breeds. This confirmed British findings but points out to the fact that considering either MRS or targeted surveillance data alone may possibly create biases in epidemiological studies on BSE.     

Phenotypic ranges and relationships among carcass and meat palatability traits for fourteen cattle breeds, and heritabilities and expected progeny differences for Warner-Bratzler shear force in three beef cattle breeds

Carcass and Warner-Bratzler shear force (WBSF) data from strip loin steaks were obtained from 7,179 progeny of Angus, Brahman, Brangus, Charolais, Gelbvieh, Hereford, Limousin, Maine-Anjou, Red Angus, Salers, Shorthorn, Simbrah, Simmental, and South Devon sires. Trained sensory panel (TSP) evaluations were obtained on 2,320 steaks sampled from contemporary groups of progeny from one to five sires of each breed. Expected progeny differences for marbling and WBSF were developed for 103 Simmental sires from 1,295 progeny, 23 Shorthorn sires from 310 progeny, and 69 Hereford sires from 1,457 progeny. Pooled phenotypic residual correlations, including all progeny, showed that marbling was lowly correlated with WBSF (-0.21) and with TSP overall tenderness (0.18). The residual correlation between WBSF and TSP tenderness was -0.68, whereas residual correlations for progeny sired by the three Bos indicus breeds were only slightly different than for progeny sired by Bos taurus breeds. The phenotypic range of mean WBSF among sires across breeds was 6.27 kg, and the phenotypic range among breed means was 3.93 kg. Heritability estimates for fat thickness, marbling score, WBSF, and TSP tenderness, juiciness, and flavor were 0.19, 0.68, 0.40, 0.37, 0.46, and 0.07, respectively. Ranges in EPD for WBSF and marbling were -0.41 to +0.26 kg and +0.48 to -0.22, respectively, for Simmentals; -0.41 to +0.36 kg and 0.00 to -0.32, respectively, for Shorthorns; and -0.48 to +0.22 kg and +0.40 to -0.24, respectively, for Herefords. More than 20% of steaks were unacceptable in tenderness. Results of this study demonstrated that 1) selection for marbling would result in little improvement in meat tenderness; 2) heritability of marbling, tenderness, and juiciness are high; and 3) sufficient variation exists in WBSF EPD among widely used Simmental, Shorthorn, and Hereford sires to allow for genetic improvement in LM tenderness.     

Experimental Haemonchus contortus infection in three breeds of sheep

Nine- to 10-month-old Florida Native, St. Croix and Dorset/Rambouillet sheep were infected with Haemonchus contortus. The primary infection was terminated by anthelmintic treatment 9 weeks later and animals were then reinfected with H. contortus. Dorset/Rambouillet sheep showed higher fecal egg counts and decreased packed cell volumes and plasma protein levels compared with the other two breeds during the primary infection. However, no breed differences were found in total worm burdens in either primary or secondary infection. Differences between breeds were also not detected in lymphocyte responsiveness to parasite antigen, H. contortus specific mucosal antibody levels, numbers of abomasal mast cells and globule leukocytes or abomasal histamine levels.