Genetic and environmental factors affecting some measures of yield and fertility in a registered Canadian Holstein dairy herd in Iran

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200008462 ◽

2002 ◽

Vol 2002 ◽

pp. 190-190

Author(s):

Ali Toosi

Keyword(s):

Environmental Factors ◽

Genetic Parameters ◽

Dairy Herd ◽

Cattle Breeding ◽

Factors Affecting ◽

Lactation Curve ◽

Dairy Cattle Breeding ◽

Important Trait ◽

Genetic And Environmental Factors ◽

Production Characteristics

Milk production is the most important trait in dairy cattle breeding. Measures of additional traits are also important. Traits of lactation curve are important in their relation to production characteristics. The two major reasons for which dairy cows are disposed are fertility problems and low milk yield (Hansen et al.,1983). The objectives of this study were 1) To evaluate effects of some environmental factors on some measures of yield and fertility, and 2) To estimate genetic parameters for these traits applying REML procedures under sire model.

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Genetic and phenotypic parameters of productivity traits on the first three lactations in Gyr cattle herds

Genetics and Molecular Biology ◽

10.1590/s1415-47571999000200007 ◽

1999 ◽

Vol 22 (2) ◽

pp. 177-181

Author(s):

Maria do Socorro Maués Albuquerque ◽

Maria Armênia Ramalho de Freitas ◽

Roberto Luiz Teodoro

Keyword(s):

Animal Model ◽

Environmental Factors ◽

Milk Production ◽

Fixed Effects ◽

Genetic Parameters ◽

Cattle Breeding ◽

Indian Origin ◽

Selection Decisions ◽

Dairy Cattle Breeding ◽

Cattle Herds

Records of Gyr cows selected for milk production were obtained from the National Gyr Dairy Cattle Breeding Program (Embrapa/CNPGL) and analyzed, in order to estimate genetic parameters for the first three lactations and to verify the effects of some environmental factors on milk production from 1979 to 1994. Genetic parameters were estimated by REML with an animal model and a group of fixed effects that included classes of herd, year, season and age at calving. Milk production means and standard deviations were 2,183 kg, 707 kg; 2,682 kg, 762 kg and 2,638 kg, 851 kg, for first, second, and third lactations, respectively. Heritability estimates were 0.20, 0.12, and 0.19 for first, second, and third lactations, respectively, and repeatability was 0.44. Genetic correlation estimates were: 0.68 between first and second lactations, 0.84 between first and third lactations and 1.0 between second and third lactations. Results confirm other research for specialized dairy breeds and firmly suggest that even in breeds of Indian origin the best time to make selection decisions is during the first lactation.

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Genetic and Environmental Factors Affecting Immunoglobulin G Concentrations in Ewe Colostrum and Lamb Serum

Journal of Animal Science ◽

10.2527/jas1988.664855x ◽

1988 ◽

Vol 66 (4) ◽

pp. 855 ◽

Cited By ~ 35

Author(s):

R. P. Gilbert ◽

C. T. Gaskins ◽

J. K. Hillers ◽

C. F. Parker ◽

T. C. McGuire

Keyword(s):

Environmental Factors ◽

Immunoglobulin G ◽

Factors Affecting ◽

Genetic And Environmental Factors

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Environmental Factors and Genetic Parameters of Beef Traits in Fleckvieh Cattle Using Field and Station Testing

Animals ◽

10.3390/ani10112159 ◽

2020 ◽

Vol 10 (11) ◽

pp. 2159

Author(s):

Radek Filipčík ◽

Daniel Falta ◽

Tomáš Kopec ◽

Gustav Chládek ◽

Milan Večeřa ◽

...

Keyword(s):

Environmental Factors ◽

Genetic Correlation ◽

Genetic Parameters ◽

The Body ◽

Carcass Weight ◽

Genetic Trend ◽

Meat Yield ◽

Dual Purpose Cattle ◽

Genetic And Environmental Factors ◽

Daily Gain

The goal of this study was to analyze the genetic and environmental factors of selected meat yield indicators in Fleckvieh cattle in the Czech Republic, through the application of station (S) and field (F) testing methods. Data collected from fattened bulls were analyzed for F (n = 9378) and for S (n = 6346). In the F method and the S method, the values of the main meat yield indicators were as follows: carcass weight 402.91 kg (F), 339.37 kg (S); carcass daily gain 626.05 g/day (F), 609.74 g/day (S); SEUROP carcass classification 2.73 (F), 2.19 (S). Environmental factors were found to have a significant impact on the selected meat yield indicators; their heritability ranged from 0.14 (SEUROP classification) to 0.33 (dressing percentage). The genetic trend was significantly positive only in relation to those meat yield traits, which had a positive link to the size or weight of the animal. The genetic correlation between observations obtained in the S and F methods of testing was very high in relation to the carcass daily gain (0.8351) and carcass weight (0.8244), while slightly lower correlations were calculated for the SEUROP classification. A genetic evaluation of the degree of fatness is not routinely performed in Fleckvieh populations, and the newly established heritability for this trait ranges between 0.17–0.20. The genetic correlation between beef yield indicators and the exterior trait of muscularity was also established, and shows a strong link to the net daily gain, the SEUROP classification and body weight (0.79–0.97). The aim of the study was to evaluate the genetic and environmental effects on meat yield and also estimate genetic parameters for new traits. We can also state, based on the results, that a strong positive genetic trend is confirmed, especially in traits related to the size or weight of animals. This result can be used in breeding programs of dual-purpose cattle, where we can genetically improve the meat and milk yield through the body size.

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