Contribution of portal‐drained viscera to heat production in Iberian gilts fed a low‐protein diet: comparison to Landrace

Abstract

In spite of the low energetic efficiency and growth rate of Iberian compared to modern breeds, the contribution of PDV energy expenditure relative to THP was lower in Iberian compared to Landrace gilts in the present study.

Portal-drained viscera heat production in Iberian pigs fed betaine- and conjugated linoleic acid-supplemented diets

“…Anderson et al pointed out that in pigs the haematocrit value was variable. Nonetheless, in previous studies also with Iberian pigs, similar values to those in the present study were found, ranging from 30 to 31% . The haematocrit value was higher in Iberian than in improved breeds, although some authors reported similar values in modern breeds to those reported herein …”

“…When the results obtained in the present study were compared with those of studies performed under like conditions, the preprandial PBF value was similar or in the lower range of data for modern breeds in the literature and in the same range of data obtained with Iberian pigs . Postprandial reduction of PBF elicited by betaine and CLA has not been reported previously.…”

“…Postprandial reduction of PBF elicited by betaine and CLA has not been reported previously. In previous studies with Iberian pigs, postprandial PBF was much lower than in the present study; the difference likely reflects the lower feed intake of pigs in those studies. PBF in the present study was within the range reported for modern breeds under similar experimental conditions .…”

“…A literature survey would show that, in most studies on PDV heat production, pigs were fed their whole daily ration and heat production was measured over a relatively short period of time . In two previous studies, we decided to feed Iberian pigs an amount of feed proportional to the measurement period (0.25 of the daily ration was offered to the gilts for a 6 h measurement period) to better simulate the situation of Iberian pigs that spend the whole day grazing to cover their nutritional requirements . Similarly, van der Meulen et al measured nutrient flux across the PDV in growing pigs offered the daily ration in two equal portions and sampled for 12 h after the first portion.…”

“…Similarly, Stoll and Burrin reported that PDV accounted for 0.20–0.35 of whole‐body protein turnover and energy expenditure but represented only 0.04–0.06 of BW. There are few data in the literature regarding PDV O 2 consumption in native breeds, with contradictory results: one survey reported greater PDV O 2 consumption of Meishan compared with Duroc × White composite crossbred pigs, while two studies reported lower PDV O 2 consumption of Iberian compared with Landrace pigs …”