Use of infrared thermography to evaluate differences in mean body surface temperature and radiant heat loss in growing pigs

Eighty barrows were used in two experiments to determine the relationship between feed intake or dietary energy concentration and mean body surface temperature (MBST) and mean body surface radiant heat loss (MBSL) as measured using infrared thermographic images. In Exp. 1, feed intake level was varied. As expected, pigs with higher feed intake grew faster. The faster growing pigs had higher MBST and MBSL. In Exp. 2, pigs (initially 130 lb) were allotted to one of four dietary energy levels (1,250 ME/lb, 1,360 ME/lb, 1,475 ME/lb, 1,590 ME/lb). Increasing dietary ME levels increased ADG, G/F, ME intake, MBST, and MBSL. These experiments indicate that infrared thermography can detect MBST and MBSL changes in growing pigs caused by changes in dietary intake or energy level

Effects of branched chain amino acids on sow and litter performance

Three hundred-six sows were used to evaluate effects of the interrelationship among valine, isoleucine, and leucine on sow and litter performance. Eight dietary treatments were arranged as a 2x2x2 factorial with two levels of valine (.80 and 1.20%), isoleucine (.68 and 1.08%), and leucine (1.57 and 1.97%). Litter weaning weight, litter weight gain from d 2 to weaning, and sow backfat loss increased as dietary valine increased but were not affected by dietary isoleucine or leucine. Increasing dietary valine, isoleucine, or leucine did not affect milk fat, DM, CP, or lactose. These results confirm the importance of dietary valine for increased litter weaning weight, independent of either additional dietary isoleucine or leucine

Infrared thermography of swine body surface temperatures and associated rectal temperatures during an acute respiratory disease challenge

An acute Actinobacillus pleuropneumonia challenge was used to study changes in rectal and radiant surface temperatures over 18 h. From 3.5 to 15 h after challenge, rectal temperatures were elevated in challenged pigs compared to nonchallenged controls. From 6 through 18 h after challenge, infrared surface temperature was higher for challenged pigs versus control nonchallenged pigs. Correlation coefficient analysis indicated that surface temperature and rectal temperature were moderately correlated. These results indicate that infrared thermography will detect changes in body surface temperature associated with the acute phase febrile response and has potential as a diagnostic tool for assessing systemic changes in radiant heat production

Effects of different specialty protein sources on growth performance of starter pigs

Two hundred and ten weanling pigs were fed diets containing either soybean meal, spray-dried blood meal, spray-dried red blood cells, select menhaden fish meal, or synthetic amino acids. From d 0 to 7 postweaning, pigs fed either spray-dried whole blood meal or red blood cells had greater ADG and ADFI than pigs fed select menhaden fish meal or added synthetic amino acids. However, from d °to 14 and 0 to 21, no differences in growth performance occurred among pigs fed the various protein sources. However, pigs fed added synthetic amino acids had poorer ADG compared with the mean for pigs fed the other protein sources

Evaluation of the total sulfur amino acid requirement of finishing pigs

Sixty four gilts (initially 120 lb) were used to evaluate the effects of increasing total sulfur amino acid (TSAA):lysine ratios on growth performance and carcass characteristics. Diets included two levels of lysine (.55% and .70% total lysine) and three TSAA:lysine ratios (60, 65, and 70% of lysine) arranged in a 2 x 3 factorial. A tendency for a lysine x TSAA interaction was observed for ADG and ADFI. Increasing TSAA:lysine ratio decreased ADG and ADFI in pigs fed .55% lysine; however, ADG and ADFI were increased in pigs fed .70% lysine and 65% TSAA:lysine. Pigs fed .70% lysine had improved ADG, F/G and 10th rib fat depth compared to those fed .55% lysine. However, no effects were observed with increasing TSAA: lysine ratios. These results suggest that the TSAA requirement of finishing pigs is not greater than 60% of total lysine