Use of a stair-step compensatory gain nutritional regimen to program the onset of puberty in beef heifers1

Abstract

It was hypothesized that metabolic programming of processes underlying puberty can be shifted temporally through the use of a stair-step compensatory growth model such that puberty is optimally timed to occur at 11 to 12 mo of age. Forty crossbred beef heifers were weaned at approximately 3.5 mo of age and, after a 2-wk acclimation period, were assigned randomly to 1 of 4 nutritional groups: 1) low control (LC), restricted feed intake of a forage-based diet to promote BW gain of 0.5 kg/d until 14 mo of age, 2) high control (HC), controlled feed intake of a high-concentrate diet to promote BW gain of 1 kg/d until 14 mo of age, 3) stair-step 1 (SS-1), ad libitum feed intake of a high-concentrate diet until 6.5 mo of age followed by restricted access to a high-forage diet to promote BW gain of 0.35 kg/d until 9 mo of age, ad libitum feed intake of a high-concentrate diet until 11.5 mo of age, and restricted intake of a high-forage diet to promote BW gain of 0.35 kg/d until 14 mo of age, and 4) stair-step 2 (SS-2), reverse sequence of SS-1, beginning with restricted access to a high-forage diet. Body weight (every 2 wk) and circulating concentrations of leptin (monthly) were determined throughout the experiment. Concentrations of progesterone in blood samples collected twice weekly beginning at 8 mo of age were used to determine pubertal status. Body weight gain followed a pattern similar to that proposed in our experimental design. Circulating concentrations of leptin increased following distinct elevations in BW but decreased abruptly after feed intake restriction. Survival analysis indicated that the percentage of pubertal heifers in the LC group was lower (P < 0.05) than all other groups throughout the experiment. Although heifers in SS-1 were nutritionally restricted between 6.5 and 9 mo of age, the proportion pubertal by 12 mo of age did not differ (P = 0.36) from that of the HC group, with 80% and 70% pubertal in SS-1 and HC, respectively. In contrast, the proportion of heifers pubertal by 12 mo of age in the SS-2 group (40%) was lower (P < 0.05) than both HC and SS-1. However, by 14 mo of age, 90% of heifers in the SS-2 group had also attained puberty compared to only 40% of the LC group. In summary, these data provide evidence that changes in the nutritional and metabolic status during the early juvenile period can program the onset of puberty that occurs months later, allowing optimal timing of sexual maturation in replacement beef heifers.

Relationship of post-weaning growth and age at puberty in crossbred beef heifers

“…Nelore crossbred heifers had a higher heterozygosity, possibly due to a better adaptation to reach earlier puberty as described by Monteiro et al (2013). Interestingly, it was also observed that heifers fed a high concentrate diet showed a continuously high rate of body weight gain after weaning (Cardoso et al, 2014). Thus, the evaluation of different crossbred phenotypic trends for body growth on a well-controlled nutritional regimen is important to achieve a significant improvement in growth efficiency of heifers.…”

“…The reproductive neuroendocrine postnatal system accelerates puberty during earlier calfhood, from 3 to 4.5 months of age, which might be facilitated by early programming of leptin secretion in adipose tissue during juvenile development using a stair-step nutritional regimen (Cardoso et al, 2014). Recently, Alves et al (2015) described that the reduction in neuropeptide-Y innervation of gonadotropin-releasing hormone neurons occurs in response to elevated body weight gain during the juvenile period.…”

Global differential gene expression in the pituitary gland and the ovaries of pre- and postpubertal Brahman heifers

“…The TF PPARG was previously identified as a key regulator of cattle puberty, in a network prediction from genomewide association data (Fortes et al, 2010). It is feasible to speculate that PPAR signaling is important for puberty, because of its relevance to fat metabolism and the well-known interplay between nutrition, metabolism, and puberty in cattle (Cardoso et al, 2014(Cardoso et al, , 2015.…”

<b>Efeito da suplementação proteica no terço final da gestação de vacas Nelore associada a suplementação das crias em <i>creep-feeding</i> e o subseqüente desempenho produtivo e reprodutivo das bezerras e/ou novilhas</b>

“…Entretanto, há uma desvantagem relacionada ao plano nutricional deficiente ou excessivo imposto às vacas, o que pode refletir em falhas no ciclo estral, ausência de prenhez e crias com desempenho atrasado (LANNA et al, 2011 Até agora, trabalhos demonstraram o impacto na idade da puberdade com suplementação no último trimestre de gestação (Funston et al, 2010) e antes do desmame (Gasser et al, 2006a;Cardoso et al, 2014). O último trimestre de gestação é um período que os bezerros podem passar por desnutrição em sistemas de pastagem, e antes do desmame (creep-feeding) é um período em que o ganho de peso dos bezerros pode ser melhorado.…”