Identification of polymorphism in promoter region of growth hormone receptor (GHR) gene and its association with milk related traits in Holstein cows

It is widely accepted that hormones, growth factors and other agents exert their biological effects on target tissues by binding to specific receptors on the plasma membrane. The variability in constituent sequences of growth hormone receptor (GHR) gene is very important because of its major role in mammary gland development. The aim of the present study is to detect polymorphism in promoter region of GHR gene and its association with milk related traits in Holstein cows. Blood samples were randomly collected from 93 Holstein cows, transported to the laboratory and stored at -20°C for further analysis. DNA was extracted using modified salting-out method and a fragment of 836 base pair from promoter region of GHR gene was amplified by a specific primer pairs using polymerase chain reaction (PCR). The PCR products were digested by AluI restriction enzyme and electrophoresed on 2% agarose gel. Result of enzyme digestion for GHR gene, showed allele AluI(-) with the fragment sizes of 14, 75 and 747, and allele AluI(+) with the fragment sizes of 14, 75, 145 and 602 base pairs. Frequency estimation of AluI(-) and AluI(+) alleles were 56 and 44%, respectively, and mean of heterozygosity was 0.49. Statistical analysis showed that cows with AluI(+) allele had significantly higher milk protein and fat percentage at first lactation compared with cows with AluI(-/-), while there was no significant relation between different genotypes and other traits.Keywords: Growth hormone receptor, polymorphism, milk, HolsteinAfrican Journal of Biotechnology Vol. 9(33), pp. 5460-5464, 16 August, 201

Effects of Long-term Induced Hyperthyroidism on Egg Quality Traits in Cobb 500 Broiler Breeder Hens

Published data on 4-week-long administration of exogenous thyroxine in broiler breeder hens to decline the cold-induced ascites in their progeny suggest that the long-term maternal hyperthyroidism would affect egg quality characteristics traits in Cobb 500 broiler breeder hens. Seventy 47-w-old broiler breeder Cobb 500 hens (5 replicates and 7 hens each) were assigned in separate cages and allotted to two treatments, control and hyperthyroid. Thyroxine was orally administered to the hyperthyroid group (0.3 mg hen/day) for a period of 100 days consecutively. Simultaneously, distilled water was orally administered to the control group. The blood sampling was done every two weeks to analyze T3, T4, and estrogen assays, using commercially kits and the egg quality attributes were evaluated for weeks 0, 3, 6, 9, and 12. Thyroxine treatment resulted in an increase in plasma concentration of T4; however, the T3 level and estrogen were not affected. The results of this study showed that the long-term administration of thyroxine had adverse effect on the most of egg quality traits in broiler breeder hens; although the results may be distinct for treatments that using other birds, doses and duration of treatments, among the different egg quality traits of broiler breeder hens evaluated in this research. Therefore, further studies should be done to make a final conclusion to use of long-term maternal hyperthyroidism treatment to reduce the ascites incidence

Disrupting effects of lithium chloride in the rat ovary: Involves impaired formation and function of corpus luteum

Lithium is an effective drug for the treatment of bipolar disorder. Evidence suggests that lithium induces side effects on the reproductive system. We have investigated the effect of lithium chloride (LiCl) on the progesterone synthesis, the main steroid produced by corpus luteum (CL), and steroidogenic acute regulatory protein (StAR) expression, the primary mechanism of the control of CL steroidogenesis. Immature female Wistar rats (25-day-old) were injected with lithium chloride (2.0 mg/kg/day) or sterile distilled water for 15 days. All rats were induced with injection of pregnant mare's serum gonadotrophin (PMSG) on the 13th day of experiment and followed by human chorionic gonadotropin (hCG) 48 h later. The last injection of LiCl was at 12 h post-hCG injection. Blood and ovaries were collected at 4 h interval from 12 to 24 h post-hCG injection. Serum levels of progesterone were measured by ELISA and CL formation was determined by histological analysis. Then, StAR protein and gene expression were examined using immunohistochemistry and polymerase chain reaction. Results showed the severe changes in CL formation, progesterone secretion and StAR expression in LiCl-treated rats during luteinization. It is concluded that the CL formation and the critical step of progesterone synthesis were affected by LiCl in gonadotropin-induced rat ovary

Dietary Effects of Micronized Soybean Meal and in Compare with Protected Methionine on Growing Performance of Zel crossbred Lambs

This study was carried out to evaluate the effects of microwave irradiated (800 W) soybean meal (irradiated over 5 min) and ruminal protected methionine (Mepron; 3 g/day) on crossbreds Zel weight gain using 15 lambs with an average weight of 31.52±2.32 kg and similar condition score in a completely randomized design with 3 treatments in 5 replicates over 80 days. Three experimental treatements contain untreated soybean meal (T1), microwave irradiated soybean meal (T2) and supplemented with Mepron as treatment 3 (T3). Weight in 15 days and daily feed consumption was determined and dry matter and nutrients digestibility among treatments were compared. Nine of the lamb were killed and their carcasses were evaluated. Daily Dry matter intake (2218.64, 2699.03 and 2775.47 g in T1, T2 and T3 respectively), final body weight (40.08, 50.48 and 52.51 kg respectively in T1, T2 and T3), daily weight gain (135.75, 234.51 and 248 g/day respectively in T1, T2 and T3) and carcasses characteristics between the control treatment and treatments 2 and 3 was significantly different, however there were similar among T2 and T3. The results of current experiment showed that microwave irradiated soybean meal and ruminal protected methionine (Mepron) can significantly improve lamb performance and their carcasses characteristics with increase weight of expensive muscle group (standard muscle groups 1 and 3) and rib eye area

Comparison of daily weight gain and fattening characteristics between buffalo and Holstein male calves with different diets

This experiment was carried out over 180 days for comparison of daily weight gain and carcass characteristics of male buffalo (BW=200.8±8.00 Kg, days from birth day=360±28) calves to Holstein male calves (BW=195.2± 10 Kg, days from birth day= 240± 22) with different diets. The 27 male buffalo calves and 27 Holstein male calves after an adaptation period and health treatment (3 weeks) allotted in factorial design (2×3) based on completely randomized design with 18 treatments. Experimental diets used to applying three treatments (three levels) of NDF, including low NDF (LNDF), medium NDF (MNDF) and high NDF (HNDF), so that final prices of these diets were different. All of these experimental calves weighted by 21 days intervals after a fasting for 12h and fed twice daily at 09.00 and 21.00 with Total Mix Ration (TMR) ad-libitum. At the end of this experiment, three replicate from each treatment were slaughtered and used for carcass analysis. The result from this experiment shows that: There was no significant difference in initial body weight in the treatments of buffalo and Holstein male calves. Both Holstein and buffalo calves have the higher FBV and best FC in LNDF diet. There was no significant difference between MNDF and HNDF in buffalo calves treatments. The proportion of abdominal fat and fat of carcass in LNDF treatment was higher. The carcass efficiency and cost of meat production in better quality per Kg was higher and lower in buffalo calves respectively especially in treatments with higher NDF

Peripheral leucocyte molecular indicators of inflammation and oxidative stress are altered in dairy cows with embryonic loss

Abstract Objective of experiment was to determine whether oxidative stress (OS) and inflammation altered embryonic loss in dairy cows. Blood samples were collected at days 0, 16, 32 and 60 after timed (AI) from 200 Holstein cows to determine embryonic loss based on interferon-stimulated gene-15 (ISG15) mRNA expression (day 16) and ultrasound at day 32 and day 60. Leucocyte expressions of mRNA TLR2, TLR4, TNF-α, IL1B, IL10, STAT3 (inflammation), PTGS2, PTGES (prostaglandin synthesis), and PLA2G4A and ALOX5AP (eicosanoid metabolism) at days 0 and 16 were determined. Plasma redox status for antioxidant enzymatic activities of glutathione peroxidase (GPX), superoxide dismutase (SOD), total antioxidant capacity (TAC), and concentrations of malondialdehyde (MDA) were determined at days 0, 16, 32 and 60. All antioxidant-redox responses were beneficially significant in pregnant cows diagnosed pregnant at day16 and sustained pregnancy to day 60 compared to non-pregnant cows at day16 or pregnant at day16 and lost embryos by days 32 or 60. The leucocyte mRNA expressions of TLR2, TLR4, STAT 3, IL1B, PTGS2, PLA2G4A and ALOX5AP were greater and PTGES was lower at day16 in pregnant cows that lost embryos early (P < 0.05). In conclusion peripheral leucocyte molecular indicators of inflammation and plasma indicators of OS were altered in pregnant cows undergoing embryonic losses compared to cows with a sustained pregnancy