Supplementation of different fat sources affects growth performance and carcass composition of finishing pigs

Background: There are various fat sources with different energy values and fatty acid compositions that may affect growth performance and carcass composition of grow-finishing pigs. A higher net energy was recently reported in choice white grease compared with soybean oil. Therefore, two experiments were conducted to determine whether practical responses confirm that difference between choice white grease and soybean oil, and to extend the observations to other fat sources.Results: In Exp. 1, pigs fed fats had lower(P < 0.05) average daily feed intake in phase II and overall period,greater(P < 0.05) gain:feed in phase I, phase II, and overall period than pigs fed the control diet. Pigs fed fats tended(P = 0.057) to have thicker backfat depth at the last rib than those fed control. Pigs fed 6% fats had greater(P < 0.01) gain:feed in phase II and overall period than pigs fed 3% fats. During phase I, pigs fed choice white grease grew faster(P < 0.05) than pigs fed soybean oil. In Exp. 2, pigs fed dietary fats(soybean oil, choice white grease, animal-vegetable blend, palm oil, or tallow) had greater(P < 0.01) gain:feed in each phase and overall period, greater(P < 0.01) average daily gain in phase I, but lower(P < 0.01) average daily feed intake in phase II an overall than pigs fed the control diets. The choice white grease also increased(P < 0.05) average daily gain during phase I compared with soybean oil. Pigs fed palm oil had thicker(P < 0.05) backfat depth at the 10 thrib than those fed soybean oil, animal-vegetable blend, or tallow.Conclusions: Inclusion of 6% dietary fat improved feed efficiency of finishing pigs, while different fats produced different practical results that may be consistent with their different energy values. Results from the early stage indicate that dietary fats with relatively more saturated fatty acids may provide greater energy than those with relatively more unsaturated fatty acids for growing pigs.

Dietary plant extracts modulate gene expression profiles in alveolar macrophages of pigs experimentally infected with porcine reproductive and respiratory syndrome virus

Background: Our previous study showed that 3 plant extracts enhanced the immune responses and growth efficiency of weaned pigs infected with porcine reproductive and respiratory syndrome virus(PRRSV), which is one of the most economically important disease in swine industry. However, each plant extract differently effected on growth efficiency and immune responses. Therefore, the objective of this study was conducted to characterize the effects and investigate the potential underlying mechanisms of 3 plant extracts on gene expression of alveolar macrophages in weaned pigs experimentally infected with PRRSV.Results: PRRSV infection altered(P < 0.05) the expression of 1,352 genes in pigs fed the control(CON;755 up, 597 down). Compared with the infected CON, feeding capsicum(CAP), garlic botanical(GAR), or turmeric oleoresin(TUR) altered the expression of 46 genes(24 up, 22 down), 134 genes(59 up, 75 down), or 98 genes(55 up, 43 down) in alveolar macrophages of PRRSV-infected pigs, respectively. PRRSV infection up-regulated(P < 0.05) the expression of genes related to cell apoptosis, immune system process, and response to stimulus, but downregulated(P < 0.05) the expression of genes involved in signaling transduction and innate immune response.Compared with the infected CON, feeding TUR or GAR reduced(P < 0.05) the expression of genes associated with antigen processing and presentation, feeding CAP up-regulated(P < 0.05) the expression of genes involved in antigen processing and presentation. Supplementation of CAP, GAR, or TUR also enhanced(P < 0.05) the expression of several genes related to amino acid metabolism, steroid hormone synthesis, or RNA degradation, respectively.Conclusions: The results suggest that 3 plant extracts differently regulated the expression of genes in alveolar macrophages of PRRSV-infected pigs, especially altering genes involved in immunity.