The effect of feed processing techniques on weanling piglet performance

[摘要] ENGLISH ABSTRACT:Starch is the main component of cereal grains and is usually the primary energy source for pigs andpoultry. Feed manufacturing can adopt several measures, including physical treatments such as millingor pelleting and other techniques, such as enzyme treatment, to disrupt cell structure. Grinding andpelleting are the most common food processing methods used for pigs. However, pelleting of completebalanced feeds is no longer such an economical proposition due to rising energy and equipment costs;therefore this cost has to be outweighed by an increased production efficiency. It has been known formany years that grinding is an essential prerequisite for the satisfactory blending of the ingredients of amulti-component food. Feed cost represents the major item in the cost of animal production. Withoutdoubt, research and production efforts will continue to refine feed processing techniques to reduce thecost of feed and to increase the value of feed for a target animal. The possibilities for improvements infeed are endless; however the cost of each innovation must be carefully weighed against demonstratedimprovements in animal performance.Experiment 1: The effect of feed processing techniques on weanling pig growth-performanceThe effects of processing of the carbohydrate source and the feed on growth performance of commercialLandrace x Large White piglets (n=480) weaned at 28 ± 2 d were investigated. Two processingcombinations of the carbohydrate source were used with 3 processing conditions of the diet in a 2 x 3factorial design. The pigs were blocked by weight (7.196 ± 2.03 kg BW) and then allotted randomly to 1of 6 dietary treatments. Ten pens of 8 piglets each were fed with each dietary treatment. The two mainprocessing conditions of the carbohydrate source were raw or extruded maize and the 3 processingconditions of the diet was meal or pelleted or extruded. No carbohydrate processing x diet processinginteractions were observed (P > 0.05) for ADG, ADFI or FeR. In this experiment, extrusion of themaize led to an significant decrease in FeR efficiency (P < 0.05) (1.57 vs. 1.42) when compared to araw maize diet. Pelleting a diet had no significant effect (P > 0.05) on ADG but tended to decrease ADFI(P < 0.07) and significantly improve FeR efficiency (1.49 vs. 1.66) when compared to a meal diet.Extruding the whole diet did not have any significant (P > 0.05) effect on ADG but tended to decreaseADFI (P < 0.07) and gave an significant improvement in FeR when compared to a meal diet (1.34 vs.1.66). This processing technique also gave a significant improvement (P < 0.01) in FeR when comparedto a pelleted diet (1.34 vs. 1.49).Experiment 2: The effect of pig feed processing conditions on pig metabolism parametersThe effects of processing of the carbohydrate source and the diet on certain metabolism and productionparameters of commercial Landrace x Large White pigs (n=24) were investigated. Two processingcombinations of the carbohydrate source were used with 3 processing combinations in a 2 x 3 factorialdesign. Six diets were formulated on an iso-nutrient basis (14.48 MJ/kg metabolizable energy (ME), 23.01 crude protein (CP), 1.092% lysine, 0.742% methionine and cystine and 0.271% tryptophan on aDM basis). The pigs were blocked by weight (26.02 ± 0.25 kg BW) and then allotted randomly to I of 6dietary treatments. The carbohydrate source was raw or extruded maize and the diets was meal orpelleted or extruded. No carbohydrate processing x diet feed form interactions were observed (P > 0.05)for dry matter intake (DMI), dry matter digestible energy (DE), Nitrogen (N) or dry matter intake(DMI). In a metabolism and nitrogen (N) balance study, apparent N digestibility, digestible energy andmetabolizable energy contents were found not to be significantly (P > 0.05) influenced by carbohydrateor diet processing.

[发布机构] Stellenbosch University