Study On The Nutritional Value Of Forage Mulberry Powder And Research In Dietary Of Finishing Pigs

Two experiments are included in the thesis. The first experiment was conducted tostudy on the nutritional value of forage mulberry for growing-finishing pigs. The secondexperiment discussed the effects of dietary mulberry leaves on the growthperformance,meat quality and apparent digestibility of dietary nutrients in finishing pigs.In the first experiment, firstly,We measure the contents of conventional nutrient inforage mulberry through chemical analysis.Secondly,six crossbred barrows were used toevaluate the nutritional value of forage mulberry.The conventional method of collectingfeces was used to determine the apparent digestibility of organic nutrients in foragemulberry and apparent digestible energy. Results were as reported below:(1)The general energy of forage mulberry the apparent digestibility and digestibleenergy of general energy were15.18MJ/kg,68.04%and9.66MJ/kg respectively; Crudeprotein content, apparent digestibility and digestible protein were19.37%,76.49%and15.33%respectively; crude fat content, apparent digestibility and digestible fat were3.43%,29.77%and1.06%respectively; and nitrogen-free extract content, apparentdigestibility and digestible nitrogen-free extract were35.42%,81.91%and33.08%respectively.(2)The content of the total essential amino acids in forage mulberry is4.81%,itaccounts for47.06%of total amino acids.The apparent digestibility of arginine,methionine, glutamate, serine and praline of forage mulberry for growing-finishing pigsis more than70%,most of the rest of the amino acid digestibility were above60%,theseshow that the most amino acids can be digested and used by growing-finishing pigs.(3)The content of unsaturated fatty acids accounted for more than half of total fattyacids in forage mulberry,the content of linolenic acid is highest,reach up to34.70%.These results indicated that forage mulberry has high nutritional value and a goodprospect of development,it also can improve the quality of animal products.We can use itas a kind of protein feed resources. The second experiment was conducted to investigate the effects of dietary mulberryleaves on the growth performance,meat quality and apparent digestibility of dietarynutrients of finishing pigs. Seventy-two finishing pigs with the same initial body weightof (65.07±1.70) kg were randomly divided into four groups with three replicates and sixpigs in every replicate. Pigs in the four groups were fed a basal diet，the basal dietcontaining10%forage mulberry, the basal diet containing15%forage mulberry and thebasal diet containing20%forage mulberry, respectively. The experiment lasted for66days. The results showed as follows:(1)Growth performance: compared with the basal diet, the average daily gain oftreatment Ⅱ、Ⅲwere not significantly changed (P>0.05), treatmentⅣ was significantlydecreased（P<0.05）, the feed to gain ratio of treatment Ⅱw as not significantly changed(P>0.05), but treatment III、IV was significantly increased（P<0.05）.(2)Meat quality indicators: compared with the basal diet, forage mulberry powdercould slow down the decrease speed of pH; compared with the basal diet,the contents offat in muscle of treatmentⅡ、 Ⅲ、 Ⅳwas significantly increased12.99%、9.97%and17.22%（P<0.05）and there was not significantly difference among threetreatments (P>0.05); compared with the basal diet, back fat thickness of treatment III、IVwere significantly decreased6.60%and8.03%（P<0.05）, but back fat thickness oftreatment Ⅱw as not significantly change (P>0.05). The relative content of linoleic acidtreatment III、IV were significantly increased35.91%and39.06%（P<0.05）comparedwith treatment Ⅰ,and treatment III、IV were significantly increased28.73%and31.71%（P<0.05）compared with treatmentⅡ. The relative content of saturated fatty acidof treatment III was significantly decreased7.32%（P<0.05）compared with treatment Ⅰ.The relative content of unsaturated fatty acid of treatment III was significantly increased4.55%（P<0.05）compared with treatment Ⅰ.The relative content of Polyunsaturatedfatty acids of finishing pigs of treatment III、IV were significantly increased32.53%and36.46%（P<0.05）compared with treatment Ⅰ.The relative content of Polyunsaturatedfatty acids of finishing pigs of treatment III、IV were significantly increased25.09%and28.79%（P<0.05）compared with treatment Ⅱand there was not significantly differencebetween treatment III and IV(P>0.05).The relative content of the total amino acid oftreatment Ⅱand III were significantly increased compared with the basal diet（P<0.05）,there was not significantly difference between treatment IV and Ⅰ（P>0.05）.For the content of single amino acid, compared with the basal diet,treatmentgroups have different degrees of improvement in eight kinds of amino acids.(3)Apparent digestibility of dietary nutrients: forage mulberry powder added had nosignificant effect on apparent digestibility of crude protein (P>0.05). The apparentdigestibility of crude fat of finishing pigs of treatment Ⅱa ndIII were significantlyincreased20.40%and27.17%compared with treatment Ⅰ（P<0.05）and there was not significantly difference between treatment Ⅰand IV; the apparent digestibility of calciumof treatment Ⅱ was significantly increased6.11%、16.78%and14.20%compared with theothers （P<0.05）and there was not significantly difference among the other treatments(P>0.05); the apparent digestibility of phosphorus of treatment IV was significantlydecreased11.31%、12.75%and10.82%compared with the others（P<0.05）,there was notsignificantly difference among treatmentⅠ、Ⅱand Ⅲ(P>0.05).The apparent digestibilityof neutral detergent fiber decreased with increasing forage mulberry powder content,compared with the basal diet, treatment III and IV were significantly decreased13.83%and15.24%(P<0.05),there was not significantly difference among treatment ⅠandⅡ(P>0.05);for the apparent digestibility of acid detergent fiber,there was not significantlydifference among treatment Ⅰ, Ⅱa nd Ⅲ (P>0.05),the apparent digestibility of aciddetergent fiber of treatment IV was significantly decreased15.77%compared with thebasal diet（P<0.05）.The result suggest that the basal diet of finishing pigs adding10%-15%foragemulberry will not affect the growth performance and could improve pork quality.