Effect of lysine to digestible energy ratio on growth performance and carcass characteristics in finishing pigs.

This experiment was performed to investigate the effects of lysine (Lys) to DE ratio on growth performance, and carcass characterics in finishing barrows. Ninety six cross-bred finishing barrows ((Landrace×Yorkshire) ×Duroc, average BW 58.25±0.48 kg) were assigned as a randomized complete block design by 2 energy levels and 4 Lys:DE ratios on the basis of BW to one of 8 treatments with 3 replications with 4 animals per pen. The levels of DE and Lys:DE ratio for each treatment were i) DE 3.35 Mcal/kg, 1.5 g Lys/Mcal DE, ii) DE 3.35 Mcal/kg, 1.8 g Lys/Mcal DE, iii) DE 3.35 Mcal/kg, 2.1 g Lys/Mcal DE, iv) DE 3.35 Mcal/kg, 2.4 g Lys/Mcal DE, v) DE 3.60 Mcal/kg, 1.5 g Lys/Mcal DE, vi) DE 3.60 Mcal/kg, 1.8 g Lys/Mcal DE, vii) DE 3.60 Mcal/kg, 2.1 g Lys/Mcal DE, viii) DE 3.60 Mcal/kg, 2.4 g Lys/Mcal DE. During finishing period from 58 kg to 103 kg of BW, increased energy density in the diet increased (p<0.05) ADG and gain:feed ratio, but did not influence ADFI. As Lys:DE ratio was increased, ADG, ADFI and gain:feed ratio were improved in finishing barrows (p<0.05). There were positive interactions (p<0.05) between carcass weight, grade, and backfat thickness and energy density and Lys level (p<0.05). In conclusion, data from our current study suggest that maximum yields including ADG, gain:feed ratio, carcass weight and grade can be achieved by administrating finishing pigs with an ideal Lys:DE ratio, Lys 2.1 g/DE Mcal.

Effects of stachyose on performance, diarrhoea incidence and intestinal bacteria in weanling pigs.

A three-week trial was conducted to evaluate the effects of the oligosaccharide stachyose on performance, diarrhoea incidence and intestinal bacterial populations in weaned pigs (7.96 +/- 0.2kg). A total of 144 crossbred (Landrace x Large White x Duroc) pigs weaned at 28 days were allotted to one of four treatments with six pens per treatment and six pigs per pen. The experimental diets were based on maize, dried whey and whole-fat milk and were supplemented with 0, 1 or 2% stachyose. A fourth diet contained no milk but instead contained 20% soybean meal to provide 0.78% stachyose and 0.21% raffinose. Inclusion of 1 or 2% stachyose in the diet depressed growth compared with pigs fed the control diet. Pigs fed the soybean meal diet gained weight at a rate similar to pigs fed the diet containing 1% added stachyose. Diarrhoea incidence was highest for pigs fed the soybean meal diet and lowest for pigs fed the control diet, with pigs fed the diets containing stachyose being intermediate. Pigs fed 1% stachyose had more lactobacilli in the ileum as well as more bifidobacteria in the caecum and colon than control pigs. They also had fewer enterobacteria in the colon. In contrast, pigs fed the diet containing 2% stachyose had fewer lactobacilli and bifidobacteria in the jejunum, ileum and caecum than did control pigs. Volatile fatty acids in the ileum, caecum and colon were highest for pigs fed 1% stachyose and lowest for pigs fed 2% stachyose. Volatile fatty acid concentrations were not significantly different between pigs fed the soybean meal diet and those fed the control. The overall results of this experiment indicate that the oligosaccharide stachyose had a negative effect on pig performance and its presence may partially explain the poorer performance observed when soybean meal is used as the sole source of supplemental protein in cereal-based diets fed to weaned pigs.

Medium-chain fatty acids but not L-carnitine accelerate the kinetics of [14C]triacylglycerol utilization by colostrum-deprived newborn pigs.

The effect of L-carnitine on in vivo fatty acid utilization was determined using colostrum-deprived newborn piglets fed emulsified triglycerides (TG) composed of [1-14C]octanoate (tri-8:0) or [1-14C]octadecanoate (tri-18:1). A soy protein-based liquid diet devoid of L-carnitine was fed piglets for 1 d to allow development of fatty acid-metabolizing enzymes and intestinal fat digestion and absorption before assessment of in vivo fat utilization. The radiolabeled TG were fed in isoenergetic amounts (97.7 kJ/kg(0.75)), with or without L-carnitine (1 mmol/kg(0.75)) as 30% (v/v) emulsions, using polyoxyethylene sorbitan monooleate as an emulsifier. Expired CO(2) was quantified and specific radioactivity (Bq/micromol) was determined at 20-min intervals over 24 h. The rate (mmol ATP.kg(-0.75).min(-1)) and extent (mol ATP/kg(0.75)) of TG oxidative utilization (i.e., composite of digestion, absorption and oxidation) were calculated from the kinetics of 14CO(2) expiration. The maximal rate and extent of tri-8:0 oxidation were three and fourfold greater than those of tri-18:1, respectively (P < 0.001), and tri-18:1 delayed the time to reach 10 and 50% of maximal oxidation rate by 1.2 and 1.9 h (P < 0.01, respectively), regardless of supplemental carnitine. Collectively, these findings quantify the accelerated oxidation of medium-chain vs. long-chain triglycerides, but fail to support a need for supplemental carnitine to maximize fat oxidation in colostrum-deprived piglets.