| Three experiments were conducted to study the effects of the optimal technical parameters on the full-fat soybean with a new-type double-helix extruder, and the practical effect of the extruded full-fat soybean on the early-weaned piglets, which include three parts ?The purpose of the first part was to study the effect of extrusion parameters on the quality of full-fat soybean and soybean meaL seven treatments were adopted to choose the optimal parameters, which included feed rate, die-hole diameter and die-hole numbers, as well as the template thickness. Results were: (l)Extrusion could decrease the Urease Activity (UA) and Protein Solubility (PS) of full fat soybean and soybean meal. The most optical parameter was the No.4 treatment., (2)After the full-fat soybean was extruded, the lose rate of lysine (12.4%) was the greatest, following with arginine, histidine, aspartic acid, methiooonine, serine and tyrosine-, while after the soybean meal was extruded, the lose of lysine reached 14.58%. (3)Extrusion could destroy the antigen in full-fat soybean and soybean meal; thus the skin-fold thickness of the raw full-fat soybean was the highest and that of the extruded was the lowest. Considering all the above results, it showed that: the feeding value of extruded full-fat soybean would be relatively high if the inside temperature was controlled at 175 癈, feed rate at 4.30 kg/min, the die-hole diameter at 2.0mm and the die-hole number at 1, template thickness at 4.5 mm. The second part was to study the effect of the extruded soybean on the growth performance and serum Blood Uinary Nitrogen(BUN) and immunoglobulin: 48 crossbred (DurocxLandrancexLarge) piglets were divided into two groups at random. Each group had three replications. The piglets were fed with extruded full-fat soybean and soybean meal supplemented with oil (control group). The result showed that: pigs fed extruded soybean had greater average daily gain (ADG) after the second week (PO.05) and during the whole period (PO.05); had shorter diarrhea period and lower diarrhea rate (P<0.01); could derease the skin-fold thickness of piglets(PO.01) . (2) Extruded diets had no effect on the IgM concentration of serum (P>0.05), but increase the IgA and IgG concentration (PO.01). (3) At the hypersensitive height, the blood uninary nitrogen (BUN) of the control and experiment were not significantly different (P>0.05). (4)Pigs fed on soybean diet had higher apparent digestibility of crude protein (PO.01), crude ash (PO.05) and organic matter (PO.05). (5) It also could decrease the cost of gaining weight, each decreased 0.48 yuan during the 28 days assay. The third part was formulated to study the effect of weaning age on the growth performance > BUN and immunoglobulin of the early-weaned piglets fed on extrudedsoybean: 48 crossbred piglets aged from 19 to 21 d and 48 aged from 26 to 28 d(DurocxLandrancexLarge) were randomly divided into two groups(weaned and not weaned) for a 35 days assay, respectly. Each group had three replications. The piglets were fed on extruded full-fat soybean, and the dietary nurtrion level met the nutrient requirement (NRC, 1998). The result showed: (1) During the first week after weaning the growth of the piglets was prevented, piglets weaned at 21d old had a higher prevented degree than those weaned at 28d old, but the body weight of 56d old (16.941 kg) was approximate to that of piglets weaned at 28d (16.84 kg) (P>0.05). (2) The average daily feed intake (ADFI) of the piglets weaned at 21d was decreased (PO.01). (3) The initial, ending and lasting time of diarrhea of the piglets weaned at 21 d was the same to those weaned at 28d, but it had an obviously higher diarrhea rate (5.23 points was increased) during the first week after weaning (PO.01). (4) The age of weaning affected the IgM concentration of the serum at time of hypersensitive height. The IgM concentration of the piglets weaned at 28d was significantly higher than those weaned at 2Id (PO.01). (5) The increase of BUN of the piglets weaned at 21d (5.44mmol/L) was sig...
|
PDF Full Text Request