Effect of glucose supplemented diet on natural and gonadotropin induced puberty attainment in gilts

Abstract

The studies were designed to assess whether a glucose-enriched diet could affect natural and/or PMSG/hCG induced puberty attainment in gilts.In Experiment 1, 145 day old crossbred gilts were randomly allocated to receive a control-standard (n=25) or glucose-supplemented diet (60 g/kg feed; n=25) for 25 days in three equal portions at 8.00, 13.00 and 18.00 h .Gilts were observed morning and afternoon for the detection of oestrus.In Experiment 2, fifty 145-155 day old prepubertal gilts were divided into two equal groups and fed for 25 days as in Experiment 1. On Day 26 of the experiment, all gilts were injected with 750 IU PMSG and 72 h later with 500 IU hCG. Three days after the last injection of gonadotropin, the gilts were slaughtered at a commercial abattoir and their reproductive tracts and carcasses were examined.Based on observations of vulval development and behavioural signs of oestrus, gilts given the glucose-enriched diet in Experiment 1 reached oestrus earlier (170.1 ±0.9 day) than the control group (175.9±1.6 day; PO.05). Also gilts given the glucose-supplemented diet showed more intense signs of oestrus than control gilts (2.8±0.4 vs 2.510.7 points, respectively; P<0.05). In Experiment 2 three gilts fed the glucose-enriched diet and three fed the control-standard diet did not respond to PMSG/hCG treatment. In the remaining animals glucose supplementation of feed increased ovulation rate (8.5±0.7 vs 6.2±0.6; PO.05) as well as ovary weight (4.9±0.5 vs 3.6±0.3 g; PO.05). Similarly, weight (356.5±23.8 vs 264.7±20.2 g) and capacity (723.0±65.8 vs 511.0+35.7 cm 3 ) of uterus were significantly (PO.01) higher in for gilts fed glucose-enriched diet than for controls.The results show that the addition of glucose to the standard diet stimulated puberty attainment and/or ovarian and reproductive tract receptiveness to PMSG/hCG in prepubertal gilts.

Influence of Estrus Synchronization of Prepubertal Gilts on Embryo Quality

“…This method enables satisfactory numbers of high quality embryos to be obtained compared to embryos collected from gilts after double synchronization. Although double synchronization did not result in higher numbers or a better quality embryos, perhaps hormonal stimulation combined with a diet enhancing insulin secretion (flushing) [14] could improve the number of good quality embryos for biotechnological studies.…”

The effectiveness of natural and gonadotropin stimulation of young gilts

“…The research which was conducted by Kapelański et al (2002;2003) have shown that the diet given for 25 days to the sexually immature gilts, increased the effectiveness of the hormonal stimulation of the estrus by eCG and hCG and increased the receptivity of the reproductive system to these gonadotropin, which has improved in a number of indicators of usability of the breeding gilts. Also, other studies have shown that the administration of a diet supplement containing corn starch and 60 g of glucose/kg feed for gilts at the age of 140-150 days, significantly increased the postprandial insulin secretion, increased the weight of the ovaries, uterus, and the number of anovulatory follicles (Zięcik et al, 2002a;Zięcik et al, 2002b).…”