Prepubertal Body Weight Research Articles

Association of POU1F1 gene polymorphism with pre-pubertal body weight in Attappady Black goats of India

The present study was carried out to identify single nucleotide variations in Pituitary specific Transcription factor – 1 (POU1F1) gene and evaluate their association with body weight at different stages of growth before the onset of puberty in meat-type Attappady Black goats. A total of 100 Attappady goats were screened for polymorphism using PCR-SSCP. Representative samples of each SSCP pattern were sequenced to ascertain the genotypes. Four fragments of POU1F1, 170 bp (exon 1), 234 bp (exon 3), 200 bp (exon 4) and 232 bp (exon 6) were analyzed. The 170 bp and 200 bp fragments were found to be monomorphic. The 234 bp fragment showed two diplotypes (GG and GA) with one synonymous single nucleotide polymorphism (g 0.42 C > T) in exon 3. The GA heterozygotes had significantly higher (p ≤ 0.05) body weight than GG homozygotes. at six months of age. The 232 bp fragment showed two diplotypes (CC and TC) with one novel synonymous single nucleotide polymorphism (g 0.180 C > T) in exon 6. The TC variants had significantly higher (p ≤ 0.05) body weight at six and nine months of age compared to the CC variants. The POU1F1 polymorphisms in the present study significantly contributed to variation in body weights at the onset of puberty at six and nine months of age indicating the role of POU1F1-mediated transcriptional regulation of genes coding for the various hormones of the neuro-endocrine system influencing growth and sexual maturity. The study suggests the possibility of using POU1F1 polymorphisms as markers for the selection of goats for higher pre-pubertal body weights in the genetic improvement programmes.

Revisiting the critical weight hypothesis for regulation of pubertal timing in boys

ABSTRACTBackgroundRecent findings indicate that there is a body weight–sensing homeostatic regulation of body weight in postpubertal rodents and humans. It is possible that body weight sensing also might be involved in the regulation of pubertal timing. Although an early small study suggested that there is a critical body weight for pubertal timing in girls, most studies have focused on BMI and reported an inverse association between BMI and pubertal timing.ObjectivesIn the present longitudinal well-powered cohort study, we revisited the critical weight hypothesis and tested if prepubertal body weight is a more robust inverse predictor of pubertal timing than prepubertal BMI in boys.MethodWe included men born during 1945–1961 (old cohort; n = 31,971) and men born during 1981–1996 (recent cohort; n = 1465) in the large BMI Epidemiology Study (BEST) Gothenburg (combined BEST cohort n = 33,436). Men with information on prepubertal body weight and BMI at 8 y of age and age at peak height velocity (PHV; an objective measure of pubertal timing) were included.ResultsBody weight explained more of the variance in age at PHV than BMI in both the old cohort and the recent cohort (combined cohort, body weight 6.3%, BMI 3.6%). Both body weight (β: −0.24 SD/SD increase in weight; 95% CI: −0.25, −0.23) and BMI (β: −0.18 SD/SD increase in BMI, 95% CI: −0.19, −0.17) were inversely associated with age at PHV but the association for body weight was significantly more pronounced than the association for BMI (P < 0.001).ConclusionsIn conclusion, prepubertal body weight is a more robust inverse predictor of pubertal timing than prepubertal BMI in boys. We propose that body weight sensing constitutes a feedback mechanism to regulate pubertal timing.

Genetic Variability in Exon 3 Region of POU1F1 Gene and its Effect on Body Weight and Milk Yield in Malabari Goats

Background: POU1F1 is known as a major candidate gene coding for pituitary-specific transcription factor-1 regulating the production of anterior pituitary hormones like GH, TSH, LH, FSH and prolactin in small ruminants. However, little is known about the genetic variability of caprine POU1F1 gene in Indian breeds. Hence, the present study aimed at the identification of single nucleotide polymorphisms in the exon 3 region of POU1F1 and their association with body weight and milk production in Malabari goats. Methods: The present study was conducted during 2016-2018 on 100 Malabari goats at the University Goat and Sheep Farm, Mannuthy. Genomic DNA was extracted using standard phenol-chloroform method. The POU1F1 exon 3 locus was PCR amplified using appropriate primers. The 234 bp PCR product was subjected to single-strand conformation polymorphism (SSCP) analysis on 12% PAGE gel and silver-stained. The different SSCP patterns were sequenced and homologous sequences identified using Blast algorithms. Allelic-genotypic frequencies and the observed-expected heterozygosity at the locus were estimated. Data on body weights at birth, three, six, nine months of age and parity-wise lactation milk yield were used to find the association of POU1F1 exon 3 variants with body weights and milk yield using one-way ANOVA in General Linear Models for fixed effects. Result: PCR-SSCP revealed GG, GA genotypes with frequencies of 0.44 and 0.56 and G and A alleles with frequencies of 0.72 and 0.28. The observed and expected heterozygosity for the locus were 0.5657 and 0.4077 respectively. Sequencing of the PCR products revealed a synonymous single nucleotide polymorphism (g. 42C&gt;T). GG homozygotes had higher body weight while GA heterozygotes had higher milk yield (p less than 0.05). It was concluded that the polymorphic exon 3 locus significantly contributed to variation in pre-pubertal body weight and milk yield and hence may be employed in the marker-assisted selection programmes for Malabari goats.

Association of prepubertal obesity with pubertal development in Chinese girls and boys: A longitudinal study.

ObjectivesThe purpose of this study was to examine the association of prepubertal body mass index (BMI) and weight status with pubertal development in boys and girls in Chongqing, China.MethodsIn a longitudinal study, 1237 students (695 boys and 542 girls) were recruited from Chongqing, China, and examined at baseline, then followed every 6 months for three and a half years. Height, weight, testicular volume, and breast development were measured at every examination. Age of first spermatorrhea and menarche were obtained from self‐report. Subjects were divided into normal weight, overweight, and obese groups according to baseline BMI. Multivariable Cox regression analysis was used to examine the association of BMI and weight status with pubertal development.ResultsIn girls, higher prepubertal BMI increased the chance of earlier menarche (hazards ratio (HR): 1.205, 95% confidence interval (95% CI): 1.151‐2.261) and breast development (HR: 1.092, 95% CI: 1.045‐1.142). Girls in the overweight (HR: 2.605, 95% CI: 1.716‐3.956) and obese (HR: 2.565, 95% CI: 1.603‐4.103) groups had an increased risk of early menarche compared with those in the normal weight group, while only overweight was associated with an increased risk for earlier breast development (HR: 1.469, 95% CI: 1.024‐2.108). In boys, higher prepubertal BMI was significantly associated with the timing of first spermatorrhea (HR: 1.054, 95% CI: 1.004‐1.106) and testicular development (HR: 1.098, 95% CI: 1.063‐1.135). Overweight (HR: 1.672, 95% CI: 1.204‐2.322) and obesity (HR: 1.598, 95% CI: 1.135‐2.249) increased the hazard of earlier testicular development compared with the normal weight group, while no significant differences were detected among the three weight groups in terms of time to first spermatorrhea.ConclusionsHigher prepubertal BMI was associated with earlier puberty in both Chinese boys and girls.

Effects of Perinatal Exposure to Phthalates and a High-Fat Diet on Maternal Behavior and Pup Development and Social Play

Humans are ubiquitously exposed to many phthalates, a class of endocrine-disrupting chemicals commonly used in many consumer goods, and diet, especially fatty food, is presumed to be a major source of exposure. Here, we use a rat model of human prenatal exposure to investigate the potential interactive effects of an environmentally relevant mixture of phthalates and a maternal high-fat diet (HFD). From gestation through postnatal day (P)10, dams consumed the mixture of phthalates (0, 200, or 1000 μg/kg/d) and were fed a control diet or HFD. In males, perinatal exposure to the mixture of phthalates decreased prepubertal body weight and, in a dose-specific manner, periadolescent social play behavior. A dose-specific effect from phthalates with HFD was also seen in increased time alone in females during social play. HFD resulted in dams consuming more calories, having greater gestational weight gain, and licking and nursing their pups more, such that an early postnatal HFD generally increased pup body weight. There also was a tendency for increased oxidative stress markers at P10 within the medial prefrontal cortex of males exposed to the relatively high dose of phthalates and HFD. Effects on gene expression were inconsistent at P10 and P90 in both the medial prefrontal cortex and hypothalamus. Overall, this study demonstrates that phthalates and a maternal HFD only rarely interacted, except in oxidative stress markers in males. Additionally, perinatal exposure to an environmentally relevant mixture of phthalates can have a modest, but lasting, impact on social behaviors in both males and females.

Effect of litter size on pre-pubertal body weight and testicular volume in crossbred boars

The objective of this study was to examine the effect of litter size on pre-pubertal body weight and testicular volume in crossbred (Landrace × Desi) boars. The body weights of the piglets in small litter were significantly higher than large litter, at all age except weaning. At 22 weeks of age, boar reared in small litter was 10 kg heavier than larger litter. The testicular volume was significantly higher in all the piglets of small litter than piglets of larger litter at 18 and 22 weeks. However, at 14 weeks, piglets of small litter showed a tendency of higher testicular volume than the piglets of larger litter size. The results of this study suggest that piglets born and reared with small litter size are beneficial to obtain higher body weight and testicular volume around puberty. This may be helpful in early selection of boars for future use in artificial insemination.

Sexual Activity and Puberty in the Male Redkaraman and Tushin (Turkish native) Lamb

Emsen, E., Köyceğiz, F. and Diaz, C.A.G. 2005. Sexual activity and puberty in the male Redkaraman and Tushin (Turkish native) lamb. J. Appl. Anim. Res., 28: 137–139. Sexual activity in the prepubertal period (120–300 days of age) and body weight, scrotal circumference and testosterone levels at puberty were studied in 10 Tushin and 8 Redkaraman male lambs. Sexual responses developed earlier (P<0.01) in Redkaraman than in Tushin ram lambs. Same was the case for age at puberty. There was no significant breed difference in body weight, scrotal circumference and testosterone levels at puberty. Scrotal circumference and body weight at puberty were correlated (P<0.01) with each other (r =0.68). It is concluded that body weight and not the age determines onset of puberty.

Effect of prepubertal body weight gain and breed on carcass composition at puberty in beef heifers

Fourteen prepubertal Angus heifers, all of which reached puberty, and 11 Santa Gertrudis (SG) heifers, eight of which reached puberty, were divided into two treatment groups. There was no breed difference in age at puberty for those that reached puberty. Treatment 1 (T1) heifers, fed to gain .5 kg/d, tended (P < .11) to be older than Treatment 2 (T2) heifers, fed to gain 1 kg/d, at puberty. Body weight and height were greater (P < .01) in SG than in Angus heifers at puberty. Angus heifers in T2 deposited more fat over the rump during the 15 wk before puberty, whereas T1 SG heifers deposited the least amount of fat (P < .05). Heifers in T2 were heavier at puberty (P < .05), had faster growing longissimus muscle areas (P < .05), and deposited more fat over the rib (P < .01) as they approached puberty. The T2 (P < .05) and Angus (P < .05) rib sections had more dissectible subcutaneous fat than did T1 and SG rib sections. Angus heifers had higher marbling scores (P < .05), as well as higher total lipid percentages for seam fat (P < .05), longissimus muscle (P < .01), other lean tissue (P < .05), and subcutaneous fat (P < .01). Predicted total lipid content for the edible portion of the dressed carcass was higher for T2 heifers (P < .09).

Sex bias or equal opportunity? Patterns of maternal investment in bison

In polygynous mammals, it may be adaptive for mothers to invest more in sons and/or to adjust the sex ratio of offspring in relation to body condition. Calving patterns were examined over an 8-year period (1982–1989) for a population of Bison bison in which barren females are not selectively culled. From these data, we tested predictions of the sex ratio adjustment hypothesis as well as two assumptions: (1) that offspring weight at the end of the period of parental investment (PI) is correlated with later condition, and (2) that maternal and offspring condition during the period of PI are correlated. In contrast to predictions, there was little evidence that mothers in better condition bear more sons. Short- and long-term measures of maternal condition (previous reproductive status, age, dominance status, pre-pubertal body weight, age at first reproduction, birth date, and the duration of the mother's own suckling period) were little related to offspring sex ratio, although the last calves of old females were nearly always female. Similarly, there was little evidence for sex-biased PI. Weights at about 7 months of age were greater for males than females; males also had somewhat later birth dates, suggesting either longer gestation or later conception. However, maternal reproductive costs, as measured by subsequent fecundity, weight loss, and interbirth intervals, did not vary with calf sex. Both assumptions of the model received some support. However, while maternal condition was correlated with offspring condition, there may be sex differences in investment patterns. Mothers appear better able to influence the condition of daughters than of sons. This sex difference may negate any benefit from male-biased investment.

Activation of growth hormone short loop negative feedback delays puberty in the female rat.

Implantation of GH in the median eminence of the hypothalamus of 23-day-old female rats tonically inhibited serum GH levels throughout prepubertal development (days 23-36) and depressed GH diurnal pulsatile release. Puberty was significantly delayed in GH-deficient animals, a delay associated with a blunted in vitro ovarian steroidal responsiveness to gonadotropins (particularly estradiol) and a marked decrease in prepubertal uterine weight, as evaluated 4, 7, and 13 days after GH implantation. The prepubertal body weight increase was also depressed. Neither ovarian weight nor serum levels of LH, FSH, PRL, or TSH were consistently altered by the GH implant. In addition, evaluation of pulsatile PRL release in 33-day-old rats revealed no difference between control and GH-deficient animals. Ovarian LH receptor content was lower in GH-implanted rats than in controls, suggesting that a decrease in LH receptors may be one of the mechanisms by which a chronic decrease in serum gH depressed the prepubertal ovarian estradiol and, to a lesser extent, the progesterone response to gonadotropins. A direct ovarian site of action for GH was indicated by the results of experiments in which GH was administered to immature hypophysectomized estrogen-treated rats. The in vitro ovarian progesterone response of the GH-treated animals to both hCG and human FSH was distinctly increased by prior in vivo GH treatment. This effect of GH was not reproduced either by the in vivo administration of LH at a dose calculated by RIA to be contaminating the GH preparation or by FSH at a dose that induced a marked increase in aromatase activity in the same ovaries. GH treatment of hypophysectomized rats failed to affect either aromatase activity or hCG-induced estradiol release, indicating that GH does not directly facilitate the production of estradiol by the ovary. The fact that intact rats with GH implants did not actually show a decrease in the ovarian estradiol response to hCG but, rather, failed to show an increased response at the same time as control animals strongly suggests that ovarian maturation was delayed in GH-deficient rats. It is suggested that, in addition to PRL, GH may also play a role in the process of prepubertal reproductive development by enhancing the steroidal response of the ovary to gonadotropins.