Attainment of puberty is a key developmental event influenced by genetic and environmental factors. In examining age at attainment of puberty, we observed closely related rams from the Davisdale line whose daughters differed in age at which they attained puberty. A candidate gene approach was used to identify mutations that may underlie these observed differences. Four rams with divergent phenotypes for their daughter's age at onset of puberty were selected for whole-genome sequencing. The coding regions of genes with known roles in regulating reproductive function were searched for single-nucleotide polymorphisms (SNPs) that altered the amino acid sequence of the protein. Of interest were three SNPs in the leptin receptor gene (LEPR). A Sequenom assay was developed to determine the genotype of these SNPs in daughters of 17 sons of a founding sire. A higher percentage of ewe lambs homozygous for the LEPR mutations failed to undergo puberty before 1 yr of age, and those that did undergo puberty during the first breeding season on average were approximately 17 days older than homozygous wild-type ewes. Heterozygous ewes were intermediate for both measurements. Given the predicted change in protein function produced by the mutation in LEPR and the strong associations between the genotype and onset of puberty phenotypes, we propose that this mutation in LEPR underlies the observed difference in age at onset of puberty in the Davisdale line. Furthermore, these animals will likely provide a useful model to better understand the role of leptin in the regulation of puberty.

Data on age and body weight at breeding, parity, previous litter size, days open and some descriptive body linear traits from 389 meat-type, prolific Black Bengal goats in Tripura State of India, were collected for 3 and 1/2 years (2007 to 2010) and analyzed using logistic regression model. The objectives of the study were i) to evaluate the effect of age and body weight at breeding, parity, previous litter size and days open on litter size of does; and ii) to investigate if body linear type traits influenced litter size in meat-type, prolific goats. The incidence of 68.39% multiple births with a prolificacy rate of 175.07% was recorded. Higher age (>2.69 year), higher parity order (>2.31), more body weight at breeding (>20.5 kg) and larger previous litter size (>1.65) showed an increase likelihood of multiple litter size when compared to single litter size. There was a strong, positive relationship between litter size and various body linear type traits like neck length (>22.78 cm), body length (>54.86 cm), withers height (>48.85 cm), croup height (>50.67 cm), distance between tuber coxae bones (>11.38 cm) and distance between tuber ischii bones (>4.56 cm) for discriminating the goats bearing multiple fetuses from those bearing a single fetus.

The aim of this study was to determine if single nucleotide polymorphisms (SNPs) in the leptin receptor (LEPR) gene associated with delayed onset of puberty are associated with changes in other reproductive traits in adult ewes. The ovulation rate of ewes homozygous for the SNPs was ~15% lower (PPLEPR SNPs than their wild-type or heterozygous contemporaries. Partial failure of multiple ovulations was also increased (PLEPR had on average 0.2 fewer lambs at mid-pregnancy and at birth compared with the wild-type or heterozygous ewes (PLEPR were strongly associated with poorer reproductive performance in Davisdale ewes, which is likely to be linked to both a reduced number of ova available for fertilisation and an increased number of ewes failing to become pregnant. Increased partial failure of multiple ovulations in ewes with high ovulation rates (i.e. 3 or greater) may also contribute to the poor reproductive performance.

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Aim:Dairy cattle health monitoring program becomes vital for detecting the febrile conditions to prevent the outbreak of the animal diseases as well as ensuring the fitness of the animals that are directly affecting the health of the consumers. The aim of this study was to validate real-time rectal temperature (RT) data of radio frequency based digital (RFD) thermometer with RT data of mercury bulb (MB) thermometer in dairy cattle.Materials and Methods:Two experiments were conducted. In experiment I, six female Jersey crossbred cattle with a mean (±standard error of the mean) body weight of 534.83±13.90 kg at the age of 12±0.52 years were used to record RT for 2 h on empty stomach and 2 h after feeding at 0, 30, 60, 90, and 120 min using a RFD thermometer as well as a MB thermometer. In experiment II, six female Jersey crossbred cattle were further used to record RT for 2 h before exercise and 2 h after exercise at 0, 30, 60, 90, and 120 min. Two-way repeated measures analysis of variance with post hoc comparisons by Bonferroni test was done.Results:Real-time RT data recorded by RFD thermometer as well as MB thermometer did not differ (p>0.05) before and after feeding/exercise. An increase (p<0.05) in RT after feeding/exercise in experimental crossbred cattle was recorded by both RFD thermometer and MB thermometer.Conclusion:The results obtained in the present study suggest that the body temperature recordings from RFD thermometer would be acceptable and thus RFD thermometer could work well for monitoring real-time RT in cattle.

Data on some linear traits along with age, body weight (BW) at breeding, parity and previous litter size (LZ) of 1008 pregnant Black Bengal goats were analysed using one-way Analysis of Variance. Higher age, heavier BW at breeding, higher parity order resulted more (P < 0.01) chance of triplet or quadruplet births as compared to that of single birth. Larger previous LZ resulted larger (P < 0.01) LZ in subsequent kidding. Most of the linear traits were higher (P < 0.01 or P < 0.05) in goats bearing multiple foetuses than in the goats bearing single foetus. The results of stepwise discriminant function suggested that heart girth, punch girth, BW, distance between trochanter major and pelvic triangle area might be the predictive indices for higher LZ.

Buffalo, the premier dairy animal in India, suffers from slow growth rate, delayed puberty, and silent heat. It is not known whether the delay in puberty in such animals is due to the delay in expression of hypothalamus-pituitary-gonadal functions. To determine the changes in growth hormone (GH), luteinizing hormone (LH), and progesterone before, at, and after puberty of Murrah buffalo heifers, six Murrah buffalo heifers (21.92 +/- 1.09 months of age, 269.67 +/- 7.97 kg body weight) were assigned to well-ventilated individual pens and fed a roughage-concentrate diet to provide weight gain of 0.4 kg/day. Blood samples were collected at 3-day intervals during a period of 12 months, and plasma harvested from blood samples was assayed for progesterone, LH, and GH. The day that plasma progesterone was greater than 1 ng/mL for three consecutive sampling days was defined as the day of puberty. Heifers attained puberty at an average age of 31.53 +/- 0.88 months with a body weight of 380.67 +/- 6.42 kg. Progesterone levels were very low (0.20 to 0.30 ng/mL) during the pre-pubertal period. There were two distinct elevations before the day of puberty onset. Plasma LH and GH concentrations increased (P < 0.05) during the months preceding puberty and were highest during the month before puberty. GH and LH were positively correlated (P < 0.05) prior to (r = +0.59) as well as after puberty (r = +0.42). A positive correlation (P < 0.05)between LH and body weight during the pre-pubertal period (r = +0.61) and thereafter, negative correlation (P < 0.05) during post-pubertal period (r = -0.64) was noted. GH and body weight showed positive correlation both before puberty (r = +0.92, P < 0.01) and after puberty (r = +0.32, P < 0.05). Results suggest that both GH and LH are equally important and vital cues in inducing onset of ovarian functions in buffalo heifers.

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