Effect Of Different Dietary Energy And Protein Sources On Growth Performance And Meat Quality Of Finishing Pigs

Effects of dietary energy and protein sources on growth performance, digestibility of nutrient, carcass traits and meat quality of finishing pigs were determined in experiment1. In combination with production practice, the application value of wheat-soybean meal in reducing production costs and improving pork quality was evaluated in experiment2.Experiment1Effects of energy and protein sources in dietary on growth performance, carcass traits and meat quality of finishing pigs60Crossbred healthy DLY (Duroc x Landrace x Yorkshire) pigs were used to determine the effect of different dietary energy and protein sources in swine diets on growth performance, digestibility of nutrient, carcass traits and meat quality and characteristics of muscle fiber of finishing pigs. The finishing pigs with an average body weight of81kg were fed with four diets. Each experimental group was comprised of5replicates with3pigs at each replicates. The diets were formulated to meet NRC nutrient requirement and to have equal levels of nutrient. Corn and wheat were the energy sources in all diets and the protein sources were soybean meal and rapeseed meal. The experiment lasted for four weeks. The results showed as follows:(1) There were no effects of different sources of energy and protein on average daily gain(ADG), average daily feed intake(ADFI) and the ratio of feed intake and gain (F/G)(P>0.05). But the feed conversion ratio was significantly higher(P<0.05) in the pigs fed corn-soybean meal than other groups. Pigs fed rapeseed meal had a greater density of urea nitrogen in serum(SUN) than pigs fed soybean meal. However, pigs fed wheat had a lower density of total protein (TP)(P<0.05) and greater density of insulin-like growth factor-1(IGF-1) in serum (P<0.05). (2)The sources of energy and protein had significant effects on pigs’nutrient digestibility. Pigs fed corn had greater digestibility of crude fat, dry matter, ash, calcium, phosphorus and energy than those fed wheat (P<0.01). Pigs fed rapeseed meal had higher digestibility of dry matter, calcium, phosphorus and energy than pigs fed soybean meal (P<0.05).(3)The sources of energy and protein had no effects on carcass quality and muscle fiber of finishing pigs. Loin muscle area was increased in pigs fed corn-soybean diets compared with pigs fed the corn-rapeseed diet (P<0.05). Sources of energy had no remarkable effects on meat quality (P>0.05).The cooking loss and content of intramuscular fat(IMF) of pigs fed rapeseed meal were significant higher than those fed soybean meal(P<0.05). At the same time, pigs fed wheat had more deposition of intramuscular fat (P<0.05).Experiment2Effects of energy sources in dietary on growth performance, carcass traits and meat quality of finishing pigs94pigs (initial BW=71kg) were used to investigate the effects of different diets on growth performance, carcass traits and pork quality of finishing pigs. The pigs were allotted randomly to two dietary treatments on the basis of weight in a randomized complete block design. The corn or wheat was used as the sole energy source in the diets. The experiment lasted for47days. The results suggested that:There was no effect of different diet on growth performance (P>0.05).The average backfat thickness and cost per weight gain was decreased by27.34%and24.58%respectively in pigs fed wheat-soybean meal. Additionally, loin muscle area was greater (P>0.05) in pigs fed wheat-soybean meal than in those fed corn-soybean meal. The muscle shear force of pigs fed wheat diet was reduced by25.26%(P<0.05). Results from this experiment suggested that pigs fed wheat-soybean meal have similar growth performance, better carcass traits and meat quality than pigs fed corn-soybean meal.In conclusion, it would cut down the cost of production and improve carcass and meat quality especially intramuscular fat (IMF) by regulating the sources of energy and protein in the diet. Moreover, it would improve economic effectiveness for producers and had important application value of the healthy and sustainable development of animal husbandry.