| Two experiments were conducted to evaluate the nutritional value of potatoprotein meal (PPM), and to study the optimum supplemental level of PPM in weanedpiglets.Experiment 1. Study on the nutritional value of potato protein meal for pigletsA digestibility trial to evaluate the nutritional value of PPM was conducted onthe basis of analyzing proximate nutrient and amino acid content. Single factorialarrangement was adopted to determine the apparent and the true ileal digestibilities ofamino acids of PPM and soybean meal (SBM) for 16±1.66kg piglets. Eighteencrossbred PIC piglets were allotted randomly to three treatments with PPM orsoybean meal (SBM) as only protein source, or N-free diet and with six replicationsper treatment. Chromium oxide(4g/kg) was included as an indigestible marker. Pigswere allowed ad libitum access to feed and water. During the experiment, all of thefeces and urine were collected to determine the protein and energy content. After theexperiment, all pigs were slaughtered to collect ileal digesta for determining the ilealdigestibilities of amino acids. Results showed that the PPM contained 18.84MJ/kgdigestible energy and 74.08% digestible protein which were 78.47% and 26.01%higher than SBM (P＜0.05).True biological value of protein was 81.05% for PPM.Contents of amino acids except Asp in PPM were higher than those of SBM.Contentsof Glu, Pro,Lys and Met were 21.17%,6.90%,5.77%,0.76% respectively, whichwere higher than those of SBM by 140.43%,232.06%,91.76%,87.50%respectively.Apparent or true ileal digestibilities for most amino acids in PPM, especially for Glu,Lys and Pro,were higher than those of SBM. Contents of true ilealdigestible Glu,Lys and Pro were 20.67%,5.58%,8.16% respectively, which werehigher than those of SBM by 194.92%,110.34%,94.87% respectively. It isconcluded that potato protein meal has higher nutritional value in terms of energyand protein content and bioavailability than soybean meal.Experiment 2. The effects of PPM on growth performance of weaned pigletsA single factorial arrangement was adopted to determine the effects of differentdietary PPM levels on protein digestibility, blood biochemical parameters and growthperformance of weaned piglets compared to spray-dried porcine plasmaprotein(SDPP). One hundred and eighty-four crossbred (Landrace×Yorkshire) pigletswith 6.94±0.69kg bodyweight were allocated into 5 groups with 4 or 5 replicates(pens)per group.All pigs were of a single genetic strain and geographical site of origin.Eachgroup was fed one of five piglet starter diets containing 0,2%,4%,6%PPM and 4%SDPP. All the group diets contained the similar level of nutrients. The trial lasted for28 days.Pigs were allowed ad libitum access to feed and water. On the 15th day of thetrial, a 4-d digestible trial was conducted to determine protein digestibility. Resultsshowed that pig performance for 2% PPM group in terms of average daily gain,average daily feed intake, feed conversion efficiency and diarrhoea incidence wassignificantly higher than the control group, close to that of 4% SDPP group. However,pigs fed diets with 4% and 6% PPM had poorer performance than control group. Withthe increase of PPM in diet, the digestibility of nitrogen increased. The digestibility ofnitrogen containing 6%PPM was significantly higher than 2%PPM and controlgroup(p＜0.05). Among all the groups, the content of total protein(TP),albumin(ALB),globulin(GLO)and the activity of choline esterase(CHE)for 2%PPM group werehighest.Compared to control group and PPM groups, the content of serum ureanitrogen(BUN) for 4%SDPP group was lower(p＜0.05). The activity of glutamic pyruvictransaminase (GPT) for 6%PPM group was higher than 4%PPM group(p＜0.05) and2%PPM group(p＜0.01).At the condition of these two studies, it is concluded that the contents and digestibilities of protein,energy and amino acids in PPM were higher than those ofSBM; the optimal dietary supplementary amount of PPM is 2% for weaned pigs. |
