Association of Genetic Variants of Casein and Milk Serum Proteins with Milk, Fat, and Protein Production by Dairy Cattle

Abstract

Polyacrylamide gel electrophoresis methods were used to phenotype caseins for 2045 cows and milk serum proteins for 3870 cows distributed in 63 Quebec dairy herds. Frequencies were: alpha s1-casein A .003, alpha s1-casein B .970, alpha s1-casein C .027; beta-casein A1 .561, beta-casein A2 .421, beta-casein A3 .011, beta-casein B .007; kappa-casein A .744, kappa-casein B .256; beta-lactoglobulin A .387, beta-lactoglobulin B .613; alpha-lactalbumin B 1.00. Overall unadjusted means for 305-day production in first lactation were: 5530 +/- 26.6 kg, 197 +/- 1.0 kg, 172 +/- 1.0 kg, 3.58 +/- .009, 3.12 +/- .009 for milk yield, fat yield, protein yield, fat percentage, and protein percentage for 1687 cows for casein systems. Similar data for 2906 cows phenotyped for milk serum proteins were: 5412 +/- 20.6 kg, 193 +/- .8 kg, 170 +/- .7 kg, 3.57 +/- .007, and 3.13 +/- 007. Least squares analysis of variance showed that herd location, month of calving, age of cow at first calving, and protein variants had significant effects on production traits. alpha s1-Casein B and beta-casein A phenotypes were associated with higher milk, fat, and protein yields than other variants in the two casein systems. Milk from kappa-casein BB and beta-lactoglobulin AA phenotypes contained .13 and .05% more protein than the AA and BB phenotypes with the AB phenotype intermediate.

Relationship Between Kappa Casein Genes (CSN3) and Industrial Yield in Holstein Cows in Nariño-Colombia

“…The results of this study are consistent with those reported by [6,7], who concluded that the BB genotype for κ-Cs determines the best milk properties for cheese production because of the greater firmness in the curd and smaller time required for the formation of small micelles. With regard to the homozygous AA genotype, these animals had lower casein contents and, as a consequence, a higher proportion of large micelles, which reduces the curd yield efficiency.…”

“…These results do not agree with those obtained by Haenlein [58] and Graml [59] in relation to the stained brown bavárico and Guernsey, who claim that cows carrying the AB genotype reach a higher milk production compared to those with the homozygous genotype AA. On the contrary, [6,60,61] they reported the highly significant effect of genotype BB on this feature in the Holstein breed.…”

Associação de SNPs nos genes para κ-caseína e β-lactoglobulina com curvas de lactação em cabras leiteiras

“…Aleandri et al (1990) relataram efeito quantitativo de variantes genotípicas do gene para β-lactoglobulina sobre a composição do leite e as propriedades do queijo. O alelo B, para β-lactoglobulina, está associado a alto teor de gordura e caseína em rebanhos leiteiros, enquanto o genótipo AA apresenta maiores teores de proteína de soro e proteína total (Ng-Kwai-Hang et al, 1984;Kumar et al, 2006). Apesar da importância da associação entre esses genes e o desempenho médio animal, representado pelas curvas de produção de leite, gordura, proteína e sólidos totais, ainda não há estudos que a utilizem na avaliação genética e fenotípica de indivíduos, em programas de seleção assistida por marcadores.…”

Application of Milk Proteins Genetic Polymorphism for Selection and Breeding of Dairy Cows in Bulgaria

“…E.g., the CSN1S1 BB genotype correlated with higher milk production in some cases (Ng-Kwai-Hang et al, 1984;Aleandri et al, 1990;Sang et al, 1994) but there was also an evidence for the superiority of the hetrozygous BC genotype (Micinski et al, 2007). Our results support the positive effect of the BC genotype on the milk yield being about 9.5% higher than the homozygous genotypes.…”