Hormonal response to dietary L-arginine supplementation in heat-stressed sows
J Pérez Laspiur, C Farmer, BJ Kerr, A Zanella, NL Trottier. 2006. Canadian Journal of Animal Science. Vol 86:373-377
11-Oct-2007 (18 years 7 months 28 days ago)During lactation, sows are under a catabolic state that may be greater under heat
stress, determining an increase in the L-arginine (Arg) requirement. The objective
of this experiment was to study the hormonal response of heat stressed sows when
diets were supplemented with Arg.
Sixty-three sows were studied in a 2x3 factorial design, with two environmental
temperatures (termoneutral vs hot) and three dietary treatments, including a basal
diet (0.96% Arg, CT), a diet containing 1.34% Arg (Medium, ME), and a diet containing
1.73% Arg (High, HI). At different stages of the lactation, and after the morning
meal, blood samples were collected from the animals to determine insulin, glucose,
growth hormone (GH) and prolactin concentrations. The sows were submitted to a
12 hours period of fasting the previous night in order to ensure the complete
consumption of the meal.
Results showed that there was not an effect of the temperature on concentrations
of any of the blood measurements, result that may be due to the standardized feed
intake conditions. On the contrary, dietary Arg supplementation determined reduced
concentrations of GH with the ME compared to the CT diet (P < 0.05). Increases
in insulin concentrations were found during the mid lactation in sows fed HI diet
compared to CT, result that could indicate a lessened catabolic state of sows.
Authors conclude that supplementation of L-arginine during lactation may have
beneficial effects on the catabolic state of lactating sows via alterations on
their insulin status.