CAJ | 학술논문

本试验旨在研究不同粗饲料组合对奶牛原料乳风味物质的影响。试验采用单因素随机试验设计,将18头体重、年龄、胎次相近的,处于泌乳中期的健康荷斯坦奶牛分为3组,每组6头,各组在采用全混合日粮饲喂的基础上调整粗饲料中干草比例,分别为羊草100%(对照组)、羊草50%+苜蓿干草50%(试验1组)、羊草50%+苜蓿干草25%+玉米秸秆25%(试验2组)。预试期15 d,正试期35 d。结果表明：1)试验1组在第36天的日产奶量显著高于对照组(P<0.05)；对照组的日产奶量在第36天、第43天、第50天比第1天显著降低(P<0.05)。试验1组较试验2组显著提高了乳脂含量(P<0.05)；试验1组和试验2组较对照组显著提高了乳蛋白和乳糖含量(P<0.05)。2)对照组醇类物质含量在第15天最高,为4.53 ng/mL,显著高于第36天和第50天(P<0.05)；试验2组醛酮类物质含量在第36天最高,为5.44 ng/mL,显著高于第15天和第50天( P <0.05)；在第15天试验2组烃类物质的含量显著高于对照组(P<0.05)；试验1组和试验2组在第50天的杂环类较第36天均显著降低(P<0.05)。结果提示,在不改变全混合日粮中精饲料的基础上,调整粗饲料组合可以增加原料乳风味物质中醇类、醛酮类物质的含量,降低不良风味物质的含量,改善乳品质,其中羊草50%、苜蓿干草25%和玉米秸秆25%的组合较好。
본시험지재연구불동조사료조합대내우원료유풍미물질적영향。시험채용단인소수궤시험설계,장18두체중、년령、태차상근적,처우비유중기적건강하사탄내우분위3조,매조6두,각조재채용전혼합일량사위적기출상조정조사료중간초비례,분별위양초100%(대조조)、양초50%+목숙간초50%(시험1조)、양초50%+목숙간초25%+옥미갈간25%(시험2조)。예시기15 d,정시기35 d。결과표명：1)시험1조재제36천적일산내량현저고우대조조(P<0.05)；대조조적일산내량재제36천、제43천、제50천비제1천현저강저(P<0.05)。시험1조교시험2조현저제고료유지함량(P<0.05)；시험1조화시험2조교대조조현저제고료유단백화유당함량(P<0.05)。2)대조조순류물질함량재제15천최고,위4.53 ng/mL,현저고우제36천화제50천(P<0.05)；시험2조철동류물질함량재제36천최고,위5.44 ng/mL,현저고우제15천화제50천( P <0.05)；재제15천시험2조경류물질적함량현저고우대조조(P<0.05)；시험1조화시험2조재제50천적잡배류교제36천균현저강저(P<0.05)。결과제시,재불개변전혼합일량중정사료적기출상,조정조사료조합가이증가원료유풍미물질중순류、철동류물질적함량,강저불량풍미물질적함량,개선유품질,기중양초50%、목숙간초25%화옥미갈간25%적조합교호。
In order to study the effects of different combinations of roughages on flavor substances in raw milk of dairy cows, eighteen Holstein cows at mid-lactation period with similar body weight, age and parity were randomly assigned to three groups with six cows in each group, based on feeding total mixed ration ( TMR) , the percentage Chinese wildrye in roughage was adjusted, which was 100% Chinese wildrye ( control group) , 50% Chinese wildrye + 50% dried alfalfa hay ( test group 1 ) , and 50% Chinese wildrye + 25% dried alfal-fa hay + 25% maize straw (test group 2), respectively. The pre-test period lasted for 15 days, and the test period lasted for 35 days. The results showed as follows:1 ) daily milk yield in test group 1 on day 36 was sig-nificantly higher than that in control group ( P<0 . 05 ); daily milk yield on days 36 , 43 and 50 was signifi-cantly decreased compared with that on day 1 ( P<0 . 05 ) . Milk fat content in test group 1 was significantly in-creased compared with that in test group 2 ( P<0 . 05 ); milk protein and lactose contents in test group 1 were significantly increased compared with those in control group ( P < 0 . 05 ) . 2 ) Esters content on day 15 (4. 53 ng/mL) was the highest, and was significantly higher than that on days 36 and 50 (P<0. 05); alde-hyde ketones content on day 36 (5. 44 ng/mL) was the highest, and was significantly higher than that on days 15 and 50 ( P<0 . 05 ); hydrocarbyls content in test group 2 on day 15 was significantly higher than that in control group ( P<0 . 05 ); heterocycles content in test groups 1 and 2 on day 50 was significantly decreased compared with that on day 36 ( P<0 . 05 ) . The results indicate that based on not changing concentrate percent-age in TMR, the adjustment of combinations of roughages can increase the contents of alcohols and aldehyde ketones, decrease the content of unacceptable flavor substances, and improve milk quality. The optimal combi-nation is 50% Chinese wildrye, 25% dried alfalfa hay and 25% maize straw.