Mutations in growth hormone gene affect stability of protein structure leading to reduced growth, reproduction, and milk production in crossbred cattle-an insight

Role of mucin 2 gene for growth in Anas platyrhynchos: a novel report

Introduction

The mucin gene is expressed in the mucous membrane of the inner layer of the internal organs. Intestinalmucin 2 (MUC2), amajor gel-formingmucin, represents a primary barrier component of mucus layers.

Materials and methods

This is the first report on the role of mucin genes in growth traits in animals. In this study, we randomly studied Bengal ducks (Anas platyrhynchos) reared from day old to 10 weeks of age under an organized farm and studied the growth parameters as well as body weight and average daily body weight gain.

Result and discussion

We characterized the mucin gene for Bengal ducks and observed glycosylation and EGF1 (EGF-like domain signature) as important domains for growth traits in ducks. We observed a better expression profile for the mucin gene in high-growing ducks in comparison to that of low-growing ducks with real-time PCR. Hence, the mucin gene may be employed as a marker for growth traits.

Differentiation of Subclinical Ketosis and Liver Function Test Indices in Adipose Tissues Associated With Hyperketonemia in Postpartum Dairy Cattle

Past studies suggested that during early lactation and the transition period, higher plasma growth hormone (GH) levels in subclinical ketosis (SCK) might involve the initiation of body adipose tissues mobilization, resulting in metabolic disorders in ruminants particularly hyperketonemia. The upregulated GH mRNA expression in adipose tissue may take part in the adipolysis process in SCK-affected cows that paves a way for study further. This study aimed to characterize the plasma levels of GH, β-hydroxybutyrate acid (BHBA) and non-esterified fatty acid (NEFA) and glucose (GLu) in ketotic cows and healthy control (CON) cows; to measure the liver function test (LFT) indices in ketotic and healthy CON cows, and finally the quantitative real-time PCR (qRT-PCR) assay of candidate genes expressed in adipose tissues of ketotic and healthy CON cows during 0 to 7 week postpartum. Three experiments were conducted. Experiment-1 involved 21 Holstein cows weighing 500–600 kg with 2–5 parities. Results showed that GH, BHBA, and NEFA levels in ketotic cows were significantly higher and the GLu level significantly lower. Pearson's correlation analysis revealed a significant positive correlation of GH with BHBA, NEFA, and GLu in ketotic and healthy CON cows. In experiment-2, dynamic monitoring of LFT indices namely, alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transpeptidase (GGT), total bilirubin (TBIL), direct bilirubin (DBIL), total protein (TP), albumin (ALB), globulin (GLOB) and albumin/globulin (A/G) were examined. The TBIL, DBIL, and GGT indices were significantly higher in ketotic cows and TP was significantly lower. In experiment-3, mRNA expression levels of GHR and peroxisome-proliferator-activated receptor alpha (PPARα) genes in adipose tissue were significantly upregulated in ketotic cows. However, the mRNA expression of insulin-like growth factor-I (IGF-1), insulin-like growth factor-I receptor (IGF-1R), and sterol regulatory element-binding protein-1c (SREBP-1c) genes in adipose tissue were downregulated in ketotic cows. Our study concluded that during postpartum, higher plasma GH levels in SCK cows might involve the initiation of body adipose tissue mobilization, resulting in hyperketonemia.

Preferred and undesirable genotypes of bGH and bIGF-1 genes for the milk yield and quality of black-and-white breed

Background and Aim:

The market demand for the quality of milk and dairy products, in particular in terms of such indicators as fat content, the amount and composition of milk protein, etc., is growing. Thus, the need for the selection of dairy herds using genetic markers associated with qualitative traits of milk productivity is becoming urgent. This study aimed to determine the preferred and undesirable genotypes of the AluI polymorphism of the growth hormone gene and SnaBI polymorphism of the insulin-like growth factor-1 gene associated with milk productivity and quality indicators of the black-and-white breed. The genotypes of animals were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Materials and Methods:

Samples of the black-and-white breed from Kazakhstan served as the research subjects. The polymorphism of the growth hormone and insulin-like growth factor-1 genes was determined by PCR-RFLP. The relationship of bGH-AluI and bIGF-1-SnaBI polymorphisms with productivity was assessed (fat, protein, and milk yield for 305 days of lactation, live weight, somatic cells, and milk production coefficient) by analysis of variance using Statistica 6.0 software.

Results:

The black-and-white cows with the bGH-Alu^ILV genotype had significantly higher milk yield in 305 days (3174.5±157.2 kg) than those with the bGH-AluI^LL (2940.0±152.6 kg) and bGH-AluI^VV genotypes (2964.0±36.0; p<0.05). The milk fat content of cows with genotypes bGH-AluI^LV and bGH-AluI^LL (121.8±6.5 and 120.6±10.2, respectively) was significantly higher than those with bGH-AluI^VV genotype (109.8±10.8; p<0.05). The black-and-white cows with the bGH-AluI^LV genotype (96.7±5.3) had significantly more milk protein than those with the bGH-AluI^LL (90.3±5.6) and bGH-AluI^VV (86.9±4.6) genotypes (p<0.05). There were no statistically significant differences in the indicators of milk productivity of cows with different genotypes of bIGF-1-SnaBI polymorphism.

Conclusion:

The results showed that the bGH-AluI^LV genotype was preferred for the black-and-white breed. The study demonstrated that genotype determined the relevant qualities, while the conditions of feeding, maintenance, and industrial technology provided the manifestation of this genotype. Thus, cows of the same (Wis Burke Ideal) line, having common ancestors in close (IV–V) ranks but living in different farming conditions, had large differences in milk productivity level. The variation was 2046 kg or 67.6% of milk per lactation.

Association of GH polymorphisms with growth traits in buffaloes

Members of the somatotrophic axis, especially GH and IGF1, are essential for growth. The association between GH polymorphisms and growth traits was numerously studied in cattle; however, no data are available for such association studies in buffalo. Therefore, this study was conducted to screen for polymorphisms in the GH gene and to study their putative association with growth traits in 200 Egyptian buffaloes. Polymerase chain reaction single-strand conformation polymorphism and sequencing were applied to look for polymorphisms in 3 loci spanning all exons and introns of buffalo GH. The C (MspI+) >T (MspI-) SNP in intron3, which is well known in cattle, was not detected in the examined buffaloes. However, 2 missense mutations were detected in exon5: one previously detected p.Leu153Val SNP, with very low frequencies for the mutant (Val) allele and one novel p.Asn174His SNP. At weaning age, the p.Leu153Val SNP was significantly associated with weaning body weight and gain with the positive effect of the wild allele (Leu) and higher GH serum, mRNA, and protein levels in animals with Leu/Asn and Leu/His haplotypes. At yearling age, the 2 SNPs associated with yearling weight and gain with positive effect for the mutant (Val and His) alleles with increased GH, and IGF1 serum, mRNA, and protein and GHR mRNA and protein levels in animals with Val/Asn haplotype. Therefore, the selection of Egyptian buffaloes with the Val/Asn haplotype could improve the growth traits of Egyptian buffaloes at yearling age which is the target age for perfect growing.