The Effect of Dextran on Chaproning Action on Beta- Casein

Представлены результаты исследований частоты встречаемости аллельных вариантов А1 и А2 гена бета-казеина (CSN2) у животных голштинской породы (n=510), принадлежащих пяти племенным хозяйствам Российской Федерации. Анализ ДНК проводился методом полимеразной цепной реакции с искусственно созданным сайтом рестрикции (ACRS-ПЦР). В среднем, по всему исследованному поголовью частота генотипов составила: A1A1—15% (n=78), A1A2—41 % (n=210), A2A2—44% (n=222). Частота желательного аллельного варианта А2 в среднем по всем стадам достигла 0,641 и превысила частоту аллеля А1 (0,359). Генотип А2А2 чаще встречается в группе племенных животных, импортированных из Дании. Им обладают 77% особей из 40 исследованных. Частота аллеля А2 в стаде исследуемого племенного хозяйства Курской области в 7 раз превысила частоту аллеля А1 и достигла 0,875. На 2-ом месте по частоте аллеля А2 находится маточное поголовье, завезенное из США. В племенном хозяйстве Московской области 42% животных из 354 исследованных имеют желательный генотип А2А2, частота аллеля А2 составила 0,640. В Камчатском крае отмечена сходная частота аллеля А2 (0,635) у племенных особей голштинской породы североамериканской селекции. В группе скота венгерской селекции, принадлежащей племенному хозяйству Рязанской области, частота аллеля А2 гена CSN2 ниже (0,611). В другом хозяйстве этого региона у голштинской породы канадского происхождения частота аллеля А1 (0,522) превысила частоту аллеля А2 (0,478). По исследованному поголовью оценки наблюдаемой (Ho) и ожидаемой (He) гетерозиготности имеют сходные значения и составляют 0,430 и 0,460 соответственно. The results of studies of the frequency of occurrence of allelic variants A1 and A2 of the beta-casein gene (CSN2) in Holstein animals (n=510) belonging to five breeding farms of the Russian Federation are presented. DNA analysis was performed by polymerase chain reaction with an artificially created restriction site (ACRS-PCR). On average, the frequency of genotypes for the entire studied population was: A1A1-15% (n=78), A1A2—41% (n=210), A2A2—44% (n=222). The frequency of the desired A2 allele variant reached 0.641 on average across all herds and exceeded the frequency of the A1 allele (0.359). The A2A2 genotype is more common in a group of breeding animals imported from Denmark. It is possessed by 77% of the 40 individuals studied. The frequency of the A2 allele in the herd of the studied breeding farm of the Kursk region was 7 times higher than the frequency of the A1 allele and reached 0.875. On the 2nd place in the frequency of the A2 allele is the breeding stock imported from the United States. In the breeding farm of the Moscow region, 42% of the 354 animals studied have the desired genotype A2A2, the frequency of the A2 allele was 0.640. In the Kamchatka Territory, a similar frequency of the A2 allele (0.635) was observed in cows of the Holstein breed of North American selection. In the group of Hungarian-bred cattle belonging to the Ryazan Region breeding farm, the frequency of the A2 allele of the CSN2 gene is lower (0.611). In another farm in this region, the Holstein breed of Canadian origin had the frequency of the A1 allele (0.522) higher than the frequency of the A2 allele (0.478). For the studied livestock, the estimates of observed (Ho) and expected (He) heterozygosity have similar values and are 0.430 and 0.460, respectively.

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Detection of A1 and A2 Alleles at Beta-casein Locus in Bargur and Umblachery (Indian Zebu) Cattle Breeds by Allele-specific PCR

Indian Journal of Animal Research ◽

10.18805/ijar.b-4273 ◽

2021 ◽

Author(s):

A. Raja ◽

R. Rajendran ◽

P. Ganapathi

Keyword(s):

Information Content ◽

Polymorphism Information Content ◽

Zebu Cattle ◽

Effective Number ◽

Cattle Breeds ◽

Specific Pcr ◽

Genotype Frequencies ◽

Beta Casein ◽

Allele Specific ◽

Allele Specific Pcr

Background: Many genetic variants of beta-casein in different breeds of cattle have been reported. The A1 and A2 are the most common variants. The breeds of Zebu cattle have high frequency of A2 allele or monomorphic for A2 allele. The current study aimed to screen Indian Zebu cattle breeds, Bargur and Umblachery, for A1 and A2 alleles at beta-casein locus.Methods: A total of 48 Bargur and 42 Umblachery cattle were genotyped for β-casein (CSN2) gene using allele-specific PCR. The gene and genotype frequencies were estimated. The theoretical heterozygosity (Heexp), experimental heterozygosity (Heobs), polymorphism information content (PIC), expected homozygosity (E), effective number of alleles (ENA) and level of possible variability realization (V%) were calculated.Result: The investigation revealed the presence of both A1 and A2 alleles at beta-casein locus in both Bargur and Umblachery cattle breeds. The A1A1 genotype was not observed in both the breeds. The frequencies of A1A2 and A2A2 genotypes were 0.125 and 0.875 respectively in Bargur and 0.050 and 0.950 respectively in Umblachery breed. The study indicated the predominance of A2 variant in both the breeds. The frequencies of A1 and A2 alleles were 0.063 and 0.937 respectively in Bargur and 0.02 and 0.98 respectively in Umblachery breed. The values of experimental heterozygosity (Heobs), theoretical heterozygosity (Heexp), polymorphism information content (PIC), expected homozygosity (E), effective number of alleles (ENA), level of possible variability realization (V%) were 0.125, 0.1163, 0.1095,0.8837, 1.131 and 11.88 respectively in Bargur breed. These values were 0.048, 0.0468, 0.0458, 0.9532, 1.049 and 4.79 respectively in Umblachery population. The observed heterozygosity and PIC values revealed the existence of very low genetic variability in the tested populations. The present work will be a contribution to the study on beta-casein locus in Indian zebu cattle.

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Absorption of beta-casomorphins from autoperfused lamb and piglet small intestine

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1990.259.3.g443 ◽

1990 ◽

Vol 259 (3) ◽

pp. G443-G452 ◽

Cited By ~ 3

Author(s):

L. C. Read ◽

A. P. Lord ◽

V. Brantl ◽

G. Koch

Keyword(s):

Small Intestine ◽

Intestinal Lumen ◽

Physiological Conditions ◽

Naturally Occurring ◽

Gut Epithelium ◽

Measured Absorption ◽

Beta Casein ◽

Kinetics Of

beta-Casomorphins (beta-CMs) derived from milk beta-casein may exert various opiate activities in milk-fed infants. To assess the physiological significance of beta-CMs as a source of circulating opioids in infants, we measured absorption rates of several beta-CMs under near-physiological conditions using in situ autoperfused lamb intestine. The naturally occurring beta-CMs, beta-CM-7 and beta-CM-4-amide, were absorbed readily into blood with no transfer into lymph. Uptake peaked within several minutes of the luminal infusion of peptide but then declined sharply and stopped within a further 10-15 min. The recovery in blood, intestinal contents, and tissue at the end of the 30-min experiment was less than 1% of the infused dose. The low recovery was due to rapid proteolysis based on in vitro studies that demonstrated half-lives of less than 5 min in lamb blood, luminal contents, and lymph. The synthetic dipeptidyl peptidase IV-resistant analogue beta-[D-Ala2]CM- 4-amide was stable during incubation in blood, lymph, or luminal contents and was absorbed into blood at rates that were maximal within several minutes and remained steady for the 30-min period. We conclude that although natural beta-CMs are transferred across the lamb small intestine, rapid degradation within the intestinal lumen, gut epithelium, and blood would prevent entry into the circulation under normal conditions. Val-beta-CM-7, a putative stable precursor, had similar stability and kinetics of absorption to beta-CM-7, results that exclude Val-beta-CM-7 as a stable precursor for delivery of beta-CMs to the circulation. Essentially identical results to those in lambs were obtained in 7-day-old piglets.

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Substrate specificity of the milk-clotting enzyme from Irpex lacteus on .KAPPA.- and .BETA.-casein.

Agricultural and Biological Chemistry ◽

10.1271/bbb1961.49.1621 ◽

1985 ◽

Vol 49 (6) ◽

pp. 1621-1631 ◽

Cited By ~ 6

Author(s):

Hideyuki KOBAYASHI ◽

Isao KUSAKABE ◽

Saeko YOKOYAMA ◽

Kazuo MURAKAMI

Keyword(s):

Substrate Specificity ◽

Irpex Lacteus ◽

Milk Clotting ◽

Milk Clotting Enzyme ◽

Beta Casein

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Genetic polymorphism of milk protein loci in Argentinian Holstein cattle

Genetics and Molecular Biology ◽

10.1590/s1415-47572000000400019 ◽

2000 ◽

Vol 23 (4) ◽

pp. 819-823 ◽

Cited By ~ 5

Author(s):

Adriana Gloria Bonvillani ◽

Miguel Angel Di Renzo ◽

Iván Nicolás Tiranti

Keyword(s):

Genetic Polymorphism ◽

Milk Protein ◽

Genotypic Diversity ◽

Genetic Distances ◽

Holstein Cattle ◽

Starch Gel Electrophoresis ◽

Beta Casein ◽

Hardy Weinberg Equilibrium ◽

Quality Of Milk ◽

Beta Lactoglobulin

Some alleles of milk protein loci are associated with superior cheese production characteristics. The genetic polymorphism of the milk protein loci alphas1-casein, beta-casein, k-casein and beta-lactoglobulin was examined in Argentinian Holstein cattle. Samples from 12 herds of four regions of Córdoba were analyzed by starch gel electrophoresis. The chi² test was used to assess whether the populations were in Hardy-Weinberg equilibrium. Genotypic diversity was analyzed by the Shannon-Weaver index. The observed genotypic frequencies were analyzed by Hedrick's genetic identity and the genetic distance of Balakrishnan and Sanghvi. The allelic and genotypic frequencies were similar to those of other Holstein populations. The genotypic frequencies of the alphas1-casein and beta-casein loci were in equilibrium, whereas in some populations the k-casein and beta-lactoglobulin loci were not. According to the Shannon-Weaver index the total genetic diversity within each herd was greater than 96%. The high values of identity agreed with the low genetic distances among populations. We conclude that there is extensive genetic homogeneity in Holstein cattle in Córdoba Province and that it would be feasible to select for B alleles at the k-casein and b-lactoglobulin loci in order to improve the quality of milk available for cheese manufacturing.

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