放牧绵羊瘤胃纤毛虫种类分布及补饲对它的影响

RUMEN CILIATE PROTOZOAL FAUNA AND COMPOSITION OF THE GRAZING SHEEP AND EFFECT OF SUPPLEMENTARY CONCENTRATED FEED ON THEM

采集了64只放牧绵羊瘤胃内容物,对其瘤胃纤毛虫种类及各属的构成比进行了检查,共检出15属39种24型。其中13种13型是从中国绵羊检出的首次记录。平均每只绵羊检出的纤毛虫种数为19.8种,平均密度为41.8×10~4/ml。属别构成比最高的是Entodinium属82.68％,最少的是Elytroplastron属是小于0.01％。 对于放牧饲养的母羊早春季节采样的5只,晚秋季节采样的9只与早春放牧羊平均每日每只补饲0.25kg精料的9只绵羊瘤胃纤毛虫种数、密度及属别构成比进行了初步调查,结果表明,春秋两季放牧绵羊纤毛虫种数相差无几,而早春放牧补饲的纤毛虫种数比春和秋不补饲的多检出10～20种。纤毛虫密度秋季的为45.3×10~4/ml,春季的31.6×10~4/ml,而早春补饲的为44.0×10~4/ml。放牧绵羊在不同季节的纤毛虫属别构成基本一致。春季放牧和放牧加补饲的绵羊瘤胃纤毛中Diploplastron属、Ostracodinium属和Enoploplastron属的构成,比秋季的分别增加了30.8～11倍。4.1～4.6倍和8.5～12.8倍。Isotoricha属、Dasytoricha属和Charon-ina属在春季补饲的比不补饲的分别增加了3.4～4.8倍、4.2～5.9倍和3.0～8.6倍,而Entod-inium属减少了10％左右。通过总的调查发现,放牧补饲的母羊瘤胃中,Entodinium dilobum种纤毛虫明显增加。

Distribution of genera and species, and generic percentage composition of the rumen ciliate protozoa were investigated on 64 grazing sheep.15 genera involving 39 species-with 24 types were identified.Of them,7 species and 12 types were newly recorded from Chinese sheep.The number of species appearing in the rumen per sheep was 19.8 on the average,and the average density of rumen ciliates was 41.8×104/ml. Of the ciliates the genus Entodinium was the most predominant and accounted for 82.6%.Elytroplastron was the lest predominant and less than 0.01%. Comparing 5 sheep which were herded in early spring with 9 sheep which were grazed in late autumn, the distribution of genera and species of the rumen ciliate protozoa were almost the same. Comparing 5 sheep and 9 sheep mentioned above with 9 sheep which were grazed in spring and supplemented with 0.25kg concentrated feed per day for each sheep, the latter had 10-20 genera and species of the rumen cliate protozoa more than that of the unsupplemented sheep.The number of total ciliates per milliliter in sheep grazing in autumn was 45.3×104 /ml, 31.6×l04/ml in sheep grazing in spring and 44.0 × 104/ml.in sheep grazing in spring with concentrated feed grazed sheep in different season without feeding concentrated feed gene ric perrcentage composition of the rumen ciliate protozoa is almost the same.The ciliate protozoa of the genus Diploplastron, Ostraoodinium and Enoploplastron of sheep which were grazed in spring increased 30.8-11.0 times, 4.1-4.6 times and 8.5-12.8 times than that of sheep which were grazed in autumn.The ciliates of the genus Isotoricha.Dasytricha and Charonina of sheep feeding concentrated feed increased 3.4-4.8 times, 4.2-5.9 times and 3.0-8.6 times than that of sheep without feeding concentrated feed.But the number of Entocinium genus decreased to 10% or so.The results show that the ciliates(Entodininm dilobum)in the rumen of sheep which were grazed and fed with concentrated feed have clearly increased.