Effect of improved nutrition during calfhood on serum metabolic hormones, gonadotropins, and testosterone concentrations, and on testicular development in bulls

Brito, Leonardo F.C.; Barth, A.D.; Rawlings, N. C.; Wilde, R.E.; Crews, D. H.; Mir, P. S.; Kastelic, John P.

doi:10.1016/j.domaniend.2006.09.004

Cited by 58 publications

(53 citation statements)

References 26 publications

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“…A linear relation in plasma testosterone with age was observed among the animals aged between 192 and 708 days. Similar changes in plasma testosterone were also noticed in investigations conducted on Egyptian buffalo bulls (Hemeida et al, 1985), Angus bull calves (Moura et al, 2001), Angus and Angus × Charolais bull calves (Brito et al, 2007), and Japanese Black bull calves (Kawate et al, 2011).…”

Section: Resultssupporting

confidence: 57%

Age-related changes in testicular parameters and their relationship to thyroid hormones and testosterone in male Murrah buffaloes

2018

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Abstract. The present study aims to investigate the age-related changes in testicular parameters and their association with plasma triiodothyronine (T 3 ), thyroxine (T 4 ), and testosterone in male Murrah buffaloes. Testicular measurements and single blood samples were collected from male Murrah buffaloes (n = 103) aged between 6 months and 8 years. The correlation coefficients of average testicular length (ATL), paired testis width (PTW), and scrotal circumference (SC) in relation to age were 0.88, 0.91, and 0.90, respectively. The regression equation between testicular weight (TW) and age was Y = 1.48 × x 0.005 (r = 0.90; R 2 = 0.79). Plasma T 4 and testosterone increased significantly (p < 0.001) with age and their levels ranged between 12.9 and 41.8 and 0.05 and 1.48 ng mL −1 , respectively. With respect to associations between testicular parameters and plasma hormone levels, we observed significant (p < 0.01) correlations between ATL, PTW, SC, TW, and plasma T 4 . A significant correlation (r = 0.31; p < 0.01) between plasma T 4 and testosterone levels was also observed. However, the correlations between plasma T 3 and testicular parameters and plasma T 3 and testosterone were non-significant. From the present study, we conclude that plasma T 4 is positively correlated with testicular parameters and plasma testosterone, indicating its role in testis development and steroidogenesis.

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Section: Resultssupporting

confidence: 57%

Age-related changes in testicular parameters and their relationship to thyroid hormones and testosterone in male Murrah buffaloes

2018

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“…A possible cause for the different findings may be breed influence, as our experiment was performed with Holstein calves whereas Hereford (Chandolia et al, 1997;Evans et al, 1993) or crossbreeds of Hereford and Charolais (Aravindakshan et al, 2000;Bagu et al, 2006) were used in the previous studies. Moreover, it has been known that diet and weight gain may also influence LH secretion and the attainment of puberty (Barth et al, 2008;Brito et al, 2007aBrito et al, , 2007b.…”

Section: Discussionmentioning

confidence: 99%

Effect of vaccination against gonadotropin-releasing factor (GnRF) with Bopriva® in the prepubertal bull calf

Janett

Gerig

Tschuor³

et al. 2012

Animal Reproduction Science

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“…Whereas increased LH pulse frequency and mean concentration during the early rise were associated with a reduced age at puberty (Evans et al 1995, Aravindakshan et al 2000, inhibiting LH secretion during the early gonadotropin rise delayed puberty in bulls (Chandolia et al 1997b). In bulls, nutrition during calfhood had direct effects on the GnRH pulse generator in the hypothalamus; low nutrition decreased LH secretion, whereas high nutrition increased secretion (Brito et al 2007a(Brito et al , 2007b. Therefore, restricted feed during calfhood may affect the early gonadotropin rise and age at puberty in bulls, regardless of the nutrition provided after this critical period of development.…”

Section: Introductionmentioning

confidence: 99%

“…Metabolic hormones such as leptin, insulin, growth hormone (GH), and insulin-like growth factor-I (IGF-I) are involved in controlling appetite and metabolism and may also be involved in regulating gonadotropin secretion. Temporal associations suggested that IGF-I might be involved in regulating LH secretion in bulls receiving varying levels of nutrition during calfhood (Brito et al 2007a(Brito et al , 2007b.…”

Section: Introductionmentioning

confidence: 99%

“…These mechanisms are largely unknown, but might involve metabolic hormones, since receptors for these hormones were detected in various cell types in the testes and these hormones affected testicular cell multiplication/differentiation and Leydig cell steroidogenesis (Cailleau et al 1990, Spiteri-Grech & Nieschlag 1992, Lin 1995, El-Hefnawy et al 2000, Wang & Hardy 2004. Circulating concentrations of metabolic hormones were associated with testes size in developing bulls (Brito et al 2007a(Brito et al , 2007c), but differences in testes weight in the absence of differences in metabolic hormone concentrations during the peripubertal period in bulls receiving varying levels of nutrition suggested that the gonadotropin-independent mechanisms involved in testicular growth are dependent on previous exposure to gonadotropins during calfhood (Brito et al 2007a(Brito et al , 2007b. Therefore, altered gonadotropin secretion during calfhood due to restricted feed may affect mature testes size in bulls.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effect of feed restriction during calfhood on serum concentrations of metabolic hormones, gonadotropins, testosterone, and on sexual development in bulls

Brito¹,

Barth²,

Rawlings³

et al. 2007

Reproduction

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The objective of the present study was to evaluate the effects of feed restriction during calfhood on serum concentrations of metabolic hormones, gonadotropins, and testosterone, and on sexual development in bulls. Eight beef bull calves received a control diet from 10 to 70 weeks of age. An additional 16 calves had restricted feed (75% of control) from 10 to 26 weeks of age (calfhood), followed by either control or high nutrition (nZ8/group) during the peripubertal period until 70 weeks of age. Restricted feed during calfhood inhibited the hypothalamic GnRH pulse generator, reduced the pituitary response to GnRH, impaired testicular steroidogenesis, delayed puberty, and reduced testicular weight at 70 weeks of age, regardless of the nutrition during the peripubertal period. Restricted feed reduced serum IGF-I concentrations, but concentrations of leptin, insulin, and GH were not affected. In conclusion, restricted feed during calfhood impaired sexual development in bulls due to adverse effects on every level of the hypothalamuspituitary-gonad axis and these effects were not overcome by supplemental feeding during the peripubertal period. Furthermore, based on temporal associations, the effects of restricted feed on the hypothalamus-pituitary-gonad axis might be mediated by serum IGF-I concentrations. These results supported the hypotheses that the pattern of LH secretion during the early gonadotropin rise during calfhood is the main determinant of age of puberty in bulls and that gonadotropin-independent mechanisms involved in testicular growth during the peripubertal period are affected by previous LH exposure.

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Effect of improved nutrition during calfhood on serum metabolic hormones, gonadotropins, and testosterone concentrations, and on testicular development in bulls

Cited by 58 publications

References 26 publications

Age-related changes in testicular parameters and their relationship to thyroid hormones and testosterone in male Murrah buffaloes

Age-related changes in testicular parameters and their relationship to thyroid hormones and testosterone in male Murrah buffaloes

Effect of vaccination against gonadotropin-releasing factor (GnRF) with Bopriva® in the prepubertal bull calf

Effect of feed restriction during calfhood on serum concentrations of metabolic hormones, gonadotropins, testosterone, and on sexual development in bulls

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