title: Prediction of scaled feed intake in weaner pigs using physico-chemical properties of fibrous feeds.
abstract: The objective of the present study was to predict scaled feed intake (SFI) using the physico-chemical measurements of feed bulk, such that gut capacity can be estimated in weaner pigs. A basal feed with 13·7 MJ digestible energy and 180 g crude protein per kg DM was diluted to six inclusion levels (0, 80, 160, 240, 320 and 400 g/kg DM) using lucerne hay, maize cob, maize stover, sawdust, sunflower husks or grass hay (veld grass). A total of 124 pigs weighing 18·1 (SD 1·37) kg body weight were used. Water-holding capacity (WHC; g water/g DM), bulk density (g DM/ml), neutral-detergent fibre (NDF) and acid-detergent fibre (ADF) influenced the SFI. The quadratic relationship between SFI and WHC was SFI = 19·1 (SEM 3·49)+10·04 (SEM 1·61) WHC-1·11 (SEM 0·17) WHC² (P<0·01). SFI was also related (P<0·01) to NDF and ADF by quadratic functions SFI = 24·3 (SEM 3·55)+0·12 (SEM 0·229) NDF - 0·00 012 (SEM 0·000036) NDF² and SFI = 30·2 (SEM 1·95)+0·112 (SEM 0·0232) ADF-0·000343 (SEM 0·0000612) ADF², respectively. Using broken-stick analyses, the gut capacity was attained when WHC = 4·53 (SEM 1·25) g water/g DM, NDF = 367 (SEM 29) g/kg DM and ADF = 138 (SEM 77) g/kg DM. In conclusion, although threshold values for each were different, WHC, NDF and ADF contents of bulk feeds provide relationships with SFI that can be used to predict gut capacity in weaner pigs.
authors: Animal and Poultry Science, University of KwaZulu-Natal, P. Bag X01 Scottsville 3209, Pietermaritzburg, South Africa.
authors: S P
authors: SP
authors: Ndou
authors: R M
authors: RM
authors: Gous
authors: M
authors: M
authors: Chimonyo
mesh_terms: D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001835:Body Weight; D004043:Dietary Fiber / Q000378:metabolism; D004044:Dietary Proteins / Q000378:metabolism; D004063:Digestion; D004435:Eating / Q000502:physiology*; D007413:Intestinal Mucosa / Q000378:metabolism; D008297:Male; D012044:Regression Analysis; D034421:Sus scrofa / Q000502:physiology*; D014886:Weaning
chemical_list: D004043:Dietary Fiber; D004044:Dietary Proteins