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1.
Johnstone AC McSporran KD Kenny JE Anderson IL Macpherson GR Jolly RD 《New Zealand veterinary journal》2004,52(6):404-408
AIM: To describe a disease of muscle in Charolais calves and confirm the putative diagnosis of inherited myophosphorylase deficiency. METHODS: Variously stained paraffin sections of muscle prepared from affected calves were used to describe the lesions. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) test was developed and applied to affected calves, their sires, dams and other individuals. RESULTS: The lesions were those of rhabdomyolysis of skeletal muscles and sub-sarcolemmal spaces in normal fibres. The PCRRFLP test confirmed the expected mutation for phosphorylase deficiency of Charolais cattle in two affected calves. In addition, sires, dams and other closely-related individuals of four affected calves tested as heterozygous for the mutation. Other apparently unrelated animals also tested as heterozygous. CONCLUSIONS: The diagnosis of myophosphorylase deficiency was confirmed. The PCR-RFLP test is suitable for use in controlling this recessively-inherited disorder as it can diagnose heterozygous individuals that are otherwise clinically normal. 相似文献
2.
Extract Myophosphorylase deficiency (glycogen storage disease Type V) has been diagnosed in Charolais calves in New Zealand. It is manifested as exercise intolerance and recumbency, usually at several weeks of age, due to an inability to mobilise glucose, as glucose phosphate, from glycogen. Affected calves may rise and walk after a rest to again become affected on further exercise. There is rhabdomyolysis and after repeated or severe attacks the calf may remain recumbent and need to be euthanised. The mutant phosphorylase gene has been described. We have established a PCR-RFLP test based on a published method, and have confirmed the diagnosis in affected calves and heterozygous status of sires, dams and other related individuals belonging to an extended family. In addition, several other non-related heterozygotes have been identified in that and another herd. There appears to have been importations of the gene from both England and America. 相似文献
3.
Soethout EC Verkaar EL Jansen GH Müller KE Lenstra JA 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2002,49(6):289-290
Myophosphorylase deficiency in cattle is a muscle disease induced by a C-->T point mutation in codon 489 of the myophosphorylase gene, which until now has only been diagnosed in the Charolais breed. The disease seems to be inherited in an autosomal monogenic recessive manner. A calf of double muscled phenotype was suspected of suffering from myophosphorylase deficiency based on typical symptoms, i.e. brown-coloured, transparent urine, occurring after exercise; exercise intolerance; symptoms of pain; and an elevated level of plasma creatine kinase. The presence of the previously described mutation was excluded using a newly developed, improved polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) procedure to identify easily heterozygous carriers and homozygous affected animals. 相似文献
4.
J J Urick O F Pahnish B W Knapp W L Reynolds W L Milmine 《Journal of animal science》1989,67(10):2603-2608
Data collected from steer and bull progeny, fed to a constant final feedlot weight over 11 yr, were used to estimate heterosis in post-weaning feedlot growth and carcass traits in two-way and three-way rotational crossing systems and a breed composite from crossing Hereford, Angus and Charolais breeds. Steer and bull progeny from matings of beef x Brown Swiss-cross sires and dams also were compared with the straight beef breeds and beef crosses. Growth traits evaluated were initial weight on test, 112-d weight, total feedlot average daily gain and total days from initial to final weight. Carcass traits included hot carcass weight, dressing percentage, rib eye area, 12th-rib fat thickness, kidney, pelvic and heart fat, yield grade and marbling score. Heterosis estimates for calves of all crossing systems were significant for initial and 112-d weight and for saving of days in the feedlot, but not for average daily feedlot gain. Heterosis estimates were small and nonsignificant for most carcass traits except for fat traits in specific crosses. Males from Hereford and Angus sires mated to Angus x Hereford dams had higher (P less than .10) backfat than did the parental average. Male progeny from Charolais ranked higher (P less than .10 to P less than .01) than calves from Hereford and Angus sires for most growth traits. Progeny from Charolais sires were more desirable (P less than .10 to P less than .01) for traits related to cutability, but they had less (P less than .05 to P less than .01) marbling than calves of Angus sires.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
Mature dams representing Hereford, Red Poll, F1 Hereford x Red Poll, F1 Red Poll x Hereford, F1 Angus x Hereford, F1 Angus x Charolais, F1 Brahman x Hereford and F1 Brahman x Angus breed types were evaluated. All cows were bred to Limousin sires to produce two-way or three-way-cross progeny. Mature Brahman x Hereford dams produced a higher (P less than .05) percentage of live calves than Herefords, but dam breed differences in percentage of calves weaned relative to the number of cows exposed for mating were not statistically significant. Progeny of Angus x Charolais and Red Poll dams were outstanding in weaning weight, but Hereford and Brahman-cross calves were below average. Planned comparisons showed that Angus x Charolais calves were heavier (P less than .01) at weaning than Hereford (23.0 +/- 3.8 kg) or Angus x Hereford (9.6 +/- 3.2 kg) progeny. Mature Angus x Hereford mothers weaned heavier calves than did Brahman x Herefords (7.4 +/- 3.2 kg, P less than .05) or Brahman x Angus (10.9 +/- 3.0 kg, P less than .01). Analysis of the Hereford-Red Poll diallel showed evidence of maternal heterosis in calf weaning weight (4.0 +/- 2.6 kg, P less than .05), but there was no difference in the percentage of calves weaned by crossbred vs straightbred dams.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
Association of myostatin on early calf mortality, growth, and carcass composition traits in crossbred cattle 总被引：3，自引：0，他引：3
The objective of this study was to investigate a potential association of an inactive myostatin allele with early calf mortality, and evaluate its effect on growth and carcass traits in a crossbred population. Animals were obtained by mating F1 cows to F1 (Belgian Blue x British Breed) or Charolais sires. Cows were obtained from mating Hereford, Angus, and MARC III (1/4 Hereford, 1/4 Angus, 1/4 Pinzgauer, and 1/4 Red Poll) dams to Hereford, Angus, Tuli, Boran, Brahman, or Belgian Blue sires. Belgian Blue was the source of the inactive myostatin allele. Myostatin genotypes were determined for all animals including those that died before weaning. Early calf mortality was examined in the F2 subpopulation (n = 154), derived from the F1 sires mated to F1 cows from Belgian Blue sires, to evaluate animals with zero, one, or two copies of inactive myostatin allele. An overall 1:2:1 ratio (homozygous active myostatin allele:heterozygous:homozygous inactive myostatin allele) was observed in the population; however, a comparison between calves dying before weaning and those alive at slaughter showed an unequal distribution across genotypes (P < 0.01). Calves with two copies of the inactive allele were more likely (P < 0.01) to die before weaning. Postweaning growth traits were evaluated in the surviving animals (n = 1,370), including birth, weaning, and live weight at slaughter, and postweaning ADG. Carcass composition traits analyzed were hot carcass weight, fat thickness, LM area, marbling score, USDA yield grade, estimated kidney, pelvic, and heart fat, retail product yield and weight, fat yield and weight, bone yield and weight, and percentage of carcasses classified as Choice. Charolais lack the inactive myostatin allele segregating in Belgian Blue; thus, in the population sired by Charolais (n = 645), only animals with zero or one copy of the inactive myostatin allele were evaluated. Animals carrying one copy were heavier at birth and at weaning, and their carcasses were leaner and more muscled. In the population sired by Belgian Blue x British Breed (n = 725), animals with two copies of inactive myostatin allele were heavier at birth, leaner, and had a higher proportion of muscle mass than animals with zero or one copies. Heterozygous animals were heaviest at weaning and had the highest live weight, whereas animals with zero copies had the highest fat content. The use of the inactive myostatin allele is an option to increase retail product yield, but considerations of conditions at calving are important to prevent mortality. 相似文献
7.
Angus (A), Santa Gertrudis (S), and Gelbvieh (G) sires were mated to A and S dams to produce five mating types (A X A, S X S, S X A, A X S and G X A) in each of four calf crops. The study involved 501 matings. Overall means for the traits measured (calves born/cows exposed, Julian birthdate, calving ease, percentage of live calves at 24 h, birth weight, survival to weaning and gestation length) were 74.2%, 48.8 d, 96.4%, 33.2 kg, 95.4% and 283.8 d, respectively. Angus dams had a 14 percentage point (P less than .05) advantage over S dams for percentage of calves born/cows exposed. The effect of heterosis in crosses of A and S for percentage of calves born/cows exposed was negative (-11.1%) and approached significance. The percentage of calves born/cows exposed were 84.4, 70.4, 76.1 and 62.3 for the A X A, S X S, S X A and A X S mating types, respectively. Matings involving A sires and dams produced calves significantly earlier in the calving season than did matings involving S sires and dams. Matings involving S sires and dams produced calves with significantly longer gestation periods than matings of A sires and dams. Calving ease score and survival to weaning were not affected by breed of sire, breed of dam, age of dam, sex of calf, or the interaction of breed of sire X breed of dam. Percentage of live calves at 24 h indicated that straightbred S calves were significantly less viable at birth than the other four mating types.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
K Pourliotis ND Giadinis G Sofianidis GD Brellou V Psychas N Roubies 《New Zealand veterinary journal》2013,61(4):244-247
CASE HISTORY A 5-day-old red deer calf was submitted with tachypnoea and dyspnoea, and was reluctant to move. CLINICAL FINDINGS: Muscular damage was established via elevated creatinine phosphokinase (CPK) activities (5,000 U/L), while concentrations of Se in whole blood were low (24.8 nmol/L). The animal died despite treatment with penicillin-streptomycin and 0.1 mg/kg Se/vitamin E administered by S/C injection. DIAGNOSIS: Necropsy and histological examination of cardiac and skeletal muscle confirmed the presumptive diagnosis of congenital white muscle disease (WMD). Prophylactic administration of a Se/vitamin E commercial preparation (as above) to another calf born in the same herd one month later was associated with good health and apparently normal growth and development. CLINICAL RELEVANCE: Congenital WMD due to Se deficiency can be fatal in red deer calves. However, prophylactic administration of Se and vitamin E to neonatal calves may be beneficial for neonatal red deer calves. 相似文献
9.
Summary Calves (n = 2) born to dams with experimentally induced brucellosis, and calves (n = 4) born to dams with naturally occurring infection were examined by the delayed‐type hypersensitivity (DTH) test for possible B. abortus infection. The results were compared with the serum agglutination test, complement fixation test, and Coombs test. Five calves were nursed by their dams for 8–10 weeks after birth. One calf was separated from its dam and fed artificial milk. Three to five months after birth, four calves tested seropositive in the serologic tests. Antibodies were detected in one calf as early as 1 week after birth. The calf fed on artificial milk was seronegative 4–5 weeks after birth. All calves reacted to the DTH test antigen from week 12 until the end of the experiment, even though serologic tests were negative. We conclude that the DTH test is a valuable technique for diagnosing Brucella in calves born to infected dams. 相似文献
10.
Heifer and steer progeny of 2-yr-old first-cross (F1) heifers and 3- to 6-yr-old F1 cows, from Hereford dams and five sire breeds, were evaluated for postweaning feedlot growth and carcass composition. Breeds of sire of dam were Angus (A), Red Poll (RP), Tarentaise (T), Simmental (Sm), and Pinzgauer (P). Calves from 2-yr-old heifers were sired by Shorthorn, and calves from 3- to 6-yr-old dams were sired by Charolais. Breed of sire of dam was significant (P less than .05 to P less than .01) for total gain and final weight for female progeny from 2-yr-old dams. At all weights, Sm, P, and T ranked above A and RP. Progeny of A, P, Sm, and T F1 2-yr-old dams were not significantly different but were higher (P less than .05) than RP heifers in total feedlot gain. Breed of sire of dam was significant (P less than .05) for carcass weight and longissimus muscle area; T ranked highest and RP lowest. Breed was not significant for any growth traits of steer progeny of 2-yr-old dams. Breed was significant for marbling score; A ranked highest and exceeded (P less than .01) both RP and Sm steers. Breed was significant (P less than .05) for most growth traits in the heifer progeny of the 3- to 6-yr-old dams bred to Charolais sires. Heifer calves of the Sm group were heavier (P less than .05) than all other groups for most weights and total gain. For total gain, P and T were intermediate and A and RP lowest. For heifer carcass traits from 3- to 6-yr-old dams, breed was significant (P less than .05 to P less than .01) for carcass weight, longissimus muscle area, percentage of cutability, and estimated kidney, heart, and pelvic fat. Heifers from Sm-sired dams were heavier (P less than .05) than those from all other groups but ranked second to heifers from P for percentage of cutability. Marbling scores of RP heifer carcasses ranked highest of all groups. Breed was not significant (P greater than .05) for any of the weights or gains in steer progeny of 3- to 6-yr-old dams; however, the Sm and P groups ranked above A and RP for all feedlot test weights.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
11.
V. P. Studdert R. B. Lavelle R. G. Beilharz T. A. Mason † 《The Journal of small animal practice》1991,32(11):557-563
The occurrence of osteochondrosis in a breeding colony of labrador retrievers during an 11-year period was investigated. Management practices and environmental factors were similar for all dogs. In 1247 progeny, elbow lameness was recorded in 259 dogs (21 per cent) and lesions of osteochondrosis on the coronoid process and, or, medial condyle of the humerus were confirmed in 189 dogs (15 per cent). None of 39 labrador crossbred dogs were affected. The incidence in progeny varied between different sires and dams and was associated with the severity of radiographic evidence of elbow arthritis in sires and dams with dams contributing significantly more than sires, suggesting a ‘maternal’ effect. 相似文献
12.
Cave JG McLaren PJ Whittaker SJ Rast L Stephens A Parker EM 《Australian veterinary journal》2008,86(4):130-135
OBJECTIVE: To report an outbreak of congenital chondrodystrophy in calves in South East Australia. METHODS: District veterinarians investigated reported cases of calf deformities. Owners of affected herds were interviewed using a standard questionnaire to identify potential risk factors. Dams of several affected calves were serologically tested for Akabane virus, Aino virus, pestivirus and bluetongue, and affected calves were tested for pestivirus antigen and serum immunoglobulin concentrations. Gross and histopathological examinations of numerous calves were performed, concentrating on the musculoskeletal system. RESULTS: A case definition of distinctive skeletal deformities was established, and 89 property owners reported calves with chondrodystrophy in Spring 2003, 2004 or 2005. Some 14 property owners reported affected calves in more than one year. Prevalence and severity of deformity varied greatly between and within properties. None of breed, sex, age of dam, lineage, pasture type, supplementary feeding, fertiliser use or toxic plants was consistently associated with the disease. All dams experienced hot, dry conditions during the first trimester of pregnancy and were exposed to adverse conditions thereafter. Consistently dams were reported to have been grazing undulating to hilly terrain during early pregnancy. All serological tests were negative for Akabane virus, Aino virus, pestivirus and bluetongue. Histopathology of affected skeletal samples showed chondrodysplasia. CONCLUSION: The outbreak had similarities with previous outbreaks reported in the region. No specific aetiology could be determined. There is some evidence that the cause of the deformities could be a manganese deficiency during foetal development. Ongoing work to test this hypothesis is therefore warranted. 相似文献
13.
Buck BC Ulrich R Kuiper H Reinacher M Peters M Heimberg P Holsteg M Puff C Haas L Ganter M Distl O 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(7-8):329-336
Profiles of blood cell counts were evaluated for 15 calves from three different farms. These calves showed petechia in the mucous membranes and in the skin and prolonged secondary bleeding after puncture. The clinical course of the disease could be observed in eleven calves. With exception of one case, the blood cell counts indicated a severe anaemia, leukocytopenia and thrombocytopenia. Out of these 15 calves, six calves survived and the other nine calves died or had to be euthanized due to the severity of the disease. Necropsy of these nine calves revealed petechia in the skin, subcutis, muscles, in inner organs and all serous membranes. Pathohistological examination showed a depletion of the bone marrow and lymphatic tissue in eight calves. These findings confirmed the diagnosis of bovine neonatal pancytopenia (BNP) for eight of these nine calves. Bluetongue virus serotype 8 was tested negatively using PCR. Bovine virus diarrhoea virus (BVDV) was negatively tested using immunofluorescence and cell culture and salmonella species were negatively tested in seven dissected calves. A cluster of toxins was negatively tested in one of the dissected calves. All 15 calves had high antibody titres for BVDV. The BVDV-antibody titres from twelve dams with affected calves were positive in six cases and not detectable in the other six cases. In three of the six dams with not detectable BVDV-antibody titres, calves were fed with colostrum of a further dam with high BVDV-antibody titres. In the further three dams without detectable BVDV-antibody titres, we could not ascertain which colostrum has been fed to the calves. BVDV-specific antigen could not be detected in any of the samples from the calves and dams tested. Using the activity of the gamma-glutamyl-transferase, we assumed a sufficient supply with colostrum for the examined calves.The cause for the occurrence of these BNP cases was due to bone marrow depletion.The reason for the bone marrow depletion remained unclear. However, it was obvious that the BNP described here is highly likely caused by colostrum from cows with positive BVDV-antibody titres. 相似文献
14.
Abstract CASE HISTORY: A 6-week-old German Holstein heifer calf (Case 1) and a 4-week-old Charolais bull calf (Case 2) were referred because of unilateral hind limb lameness. Both had been treated with systemic antibiotics by the referring veterinarian. CLINICAL FINDINGS AND DIAGNOSIS: Based on the results of clinical, radiographic and ultrasonographic examination, a diagnosis of chronic purulent septic gonitis with subchondral osteolysis of the lateral femoral condyle was made in both calves. In Case 2 the lateral tibial condyle also showed osteolysis. TREATMENT AND OUTCOME: Treatment consisted of arthrotomy with debridement of abnormal bone and cartilage via a craniolateral and a caudolateral approach. Case 1 was discharged from with grade 1/5 lameness 60 days after surgery. In a follow-up 15 months postoperatively, the owner reported that it had been bred at 14 months, was not lame and the affected stifle joint appeared normal. Case 2 had grade 2/5 lameness 52 days after surgery, but was sound at the time of slaughter at 22 months of age. CLINICAL RELEVANCE: Arthrotomy via a caudolateral approach is a suitable method for the treatment of septic purulent gonitis with osteolysis of the lateral femoral and tibial condyles in calves. In these cases, this treatment resulted in the elimination of localised inflammation, prevented clinically relevant spread of infection to other organs, and restored normal joint function. 相似文献
15.
OBJECTIVE: To determine the mode of inheritance of congenital proportionate dwarfism in Angus and Angus crossbred cattle, initially detected in two commercial beef herds in northern New South Wales. DESIGN: Matings of normal carrier sires to unrelated cows of diverse breeds, and of one carrier sire to his unaffected daughters. An unrelated Piedmontese bull was also mated to unaffected daughters of the carrier sires. PROCEDURE: Two carrier Angus bulls and nine unaffected daughters, all of whom were completely indistinguishable from normal animals, were purchased for controlled breeding studies under known nutritional and disease conditions. Affected and carrier individuals were examined for the presence of obvious chromosomal abnormalities. RESULTS: Angus dwarfism has been successfully reproduced under controlled experimental conditions over successive years using unrelated dams and is undoubtedly heritable. The high frequency of occurrence of affected individuals (23/61 = 0.38 +/- .06) among the progeny of matings of the Angus sires to unrelated females of diverse breeding is not compatible with recessive inheritance, because of the negligible frequency of proportionate dwarfism in the breeds of the dams. Both paternal and maternal transmission of the defect was demonstrated, so that imprinting in the strict sense of a gene that is only expressed when received from the male parent appears not to be involved. Tested individuals showed no evidence of gross chromosomal abnormality. Dominant autosomal inheritance with incomplete penetrance was indicated by the lack of expression of the defective gene in the two Angus sires and in three unaffected daughters who produced dwarf calves from matings to the Piedmontese bull. CONCLUSIONS: The mode of inheritance is that of a single autosomal dominant gene with a penetrance coefficient of 0.75 +/- 0.12, estimated from the observed incidence of 23/61 affected offspring of the two carrier Angus bulls mated to unrelated dams. Simple genetic models involving either (i) an unstable mutant which changes at high frequency to the expressed dominant dwarfing allele during gametogenesis, or (ii) a dominant allele with penetrance determined by an unlinked modifying locus, are shown to be compatible with the experimental data. Both models indicate that penetrance of the dwarfing gene may possibly be higher in matings involving carrier daughters of the two Angus bulls. 相似文献
16.
The organisation of the E1alpha subunit of bovine branched-chain alpha-keto acid dehydrogenase gene was established. c DNA was cloned from Poll Shorthorn x Poll Hereford calves affected with Maple Syrup Urine Disease to identify the mutation responsible for the disease in Poll Shorthorns. Clones containing the c DNA sequences inherited from the Poll Shorthorn sire of the affected calves were identified. Paternal clones were sequenced and a cytidine to thymidine transition was found at nucleotide 1380. The mutation is predicted to substitute leucine in place of a highly conserved proline at codon 372. A polymerase chain reaction procedure was developed for detection of the 1380C-->T mutation in genomic DNA. Three Poll Shorthorn parents of affected calves and three affected Poll Shorthorn x Poll Hereford calves were heterozygous and an affected Poll Shorthorn calf was homozygous for this mutation. An improved polymerase chain reaction procedure was also devised to genotype Poll Herefords for the 248C-->T mutation. The procedures will facilitate disease prevention programs and assist in differential diagnosis of conditions in new-born calves that present with a rapid onset of progressive neurological disease and are characterised histologically by 'status spongiosus'. Maple Syrup Urine Disease (MSUD) is an autosomal recessive defect reported in humans (Danner and Elsas 1989), and in Poll Hereford (PH) and Poll Shorthorn (PS) calves (Harper et al 1986, Healy et al 1992). The clinical, biochemical and pathological manifestations of the disease are identical in the two breeds of cattle, and are characterised by the rapid onset of progressive neurological disease, leading to death within a few days of birth. The disease is caused by a deficiency of activity of the mitochondrial enzyme branched-chain alpha-keto acid dehydrogenase (BCKADH). This deficiency leads to elevated concentrations, in blood and tissues, of branched chain alpha-keto acids and their precursors, the branched chain amino acids, valine, leucine and isoleucine. BCKADH consists of four subunits E1alpha, E1beta, E2 and E3 that are encoded by separate genes, and MSUD may result from deficiency of any of the subunits. In PH s, the disease in caused by premature termination of translation, of the E1alpha subunit, that is induced by a cytidine to thymidine transition exon 2 (248C-->T), that converts the glutamine codon -6 to a stop codon (Q-6ST; Zhang et al 1990). We have shown that MSUD -affected PSxPH calves are heterozygous at the PH locus, illustrating molecular heterogeneity exists for bovine MSUD (Healy and Dennis 1994a). The fact that these crossbred calves are affected, indicates the PS, like the PH mutation, resides in the E1alpha subunit. 相似文献
17.
AMJ McFadden GF Mackereth MI Avery RR Clough I Bolotovski J Fitzmaurice 《New Zealand veterinary journal》2013,61(1):63-68
AIM: To determine the aetiology of a syndrome characterised by facial paralysis in calves (facial paralysis syndrome; FPS); describe the epidemiology of the syndrome on an affected case farm; and define the intra-farm prevalence of affected calves, and inter-farm prevalence of affected dairy farms, in the Franklin district of New Zealand. CASE HISTORY AND CLINICAL FINDINGS: An investigation was carried out on a town-supply dairy farm experiencing an outbreak of FPS in calves during the autumn of 2007, following a previous outbreak during the spring of 2006; 21 calves were affected in both outbreaks. Post-mortem examinations of three affected calves revealed no infectious aetiological agent in neurological tissues despite tests for viruses, bacteria and Mycoplasma species. Tests on hepatic tissues for vanadium toxicity were inconclusive. SURVEY OF DAIRY FARMS: Results from a postal survey of 177/325 (54%) farms established the yearly prevalence of affected farms, based on farmer diagnosis, was 11%, and there was a median two (range 1–25) affected calves on those farms. There was no evidence of spatial clustering of affected farms after accounting for the underlying farm density, or of an increase in the number of affected farms between 2003 and 2007. CLINICAL RELEVANCE: Facial paralysis syndrome is an unusual condition that has not been reported in other districts of New Zealand or in other countries. It is probable that this syndrome will continue to occur at a low to moderate prevalence, and have a significant impact on a small number of farms. 相似文献
18.
Breed differences for weight (CW), height (CH), and condition score (CS) were estimated from records (n = 12,188) of 2- to 6-yr-old cows (n = 744) from Cycle IV of the U.S. Meat Animal Research Center's Germplasm Evaluation (GPE) Program. Cows were produced from mating Angus and Hereford dams to Angus, Hereford, Charolais, Shorthorn, Galloway, Longhorn, Nellore, Piedmontese, and Salers sires. Samples of Angus and Hereford sires were 1) reference sires born from 1962 through 1970 and 2) 1980s sires born in 1980 through 1987. The mixed model included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and breedgroup as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as a linear covariate. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects associated with the cow. Differences among breed groups were significant (P < 0.05) for all traits and were maintained through maturity with few interchanges in ranking. The order of F1 cows for weight was as follows: Charolais (506 to 635 kg for different ages), Shorthorn and Salers, reciprocal Hereford-Angus (HA) with 1980s sires, Nellore, HA with reference sires, Galloway, Piedmontese, and Longhorn (412 to 525 kg for different ages). Order for height was as follows: Nellore (136 to 140 cm), Charolais, Shorthorn, Salers, HA with 1980s sires, Piedmontese, Longhorn, Galloway and HA with reference sires (126 to 128 cm). Hereford and Angus cows with reference sires were generally lighter than those with 1980s sires. In general, breed differences for height followed those for weight except that F1 Nellore cows were tallest, which may in part be due to Bos taurus-Bos indicus heterosis for size. 相似文献
19.
Light Sussex and Brown Leghorn flocks were concurrently bred pure and crossed in both directions for 6 years in an experiment to test for genetic interactions (“nicking”) between individual sires and dams. The traits measured in survivors to 450 days of age were (i) egg production, 126–250 days, (ii) egg production, 250–450 days, (iii) egg production, 126–450 days, (iv) mature egg weight, (v) age at sexual maturity and (vi) pullet weight at 18 weeks.
There was little response to selection in the primary trait, egg production to 450 days. Crossbreds showed a degree of heterosis in averages of egg production and there were consistent reciprocal differences between crossbreds in egg weight and pullet weight. It was impossible to distinguish between sex linkage and maternal effects in the determination of these differences.
Analyses of variance were complicated by the breed difference and by heterogeneity of variances, but yielded little evidence of interaction in egg production either between sires and breed of dams or between dams and sires. Some significant interactions were noted in egg weight and pullet weight. A weighted covariance technique yielded high positive correlations between purebred and crossbred sire family means, and confirmed that genetic interactions were unimportant. Thus reciprocal recurrent selection would not have been advantageous for improving egg production of crossbreds from the two flocks. 相似文献
20.
Jindrich Citek 《Acta veterinaria Scandinavica》2012,54(1):22