Investigation On Parasites Infection In Black Goats In A County Of Sichuan Province

The black goat farming in the investigated counties was mainly concentrated in the five towns A,B,C,D and E(see Figure 2-1 for the regional location).Breeding methods are grazing and semi-grazing,and the scale of breeding is mainly 20-100 ewes.n May,August,November and February of the following year,the investigation of parasitic infection in black goats was carried out in the five towns.To grasp the epidemiological regularity and provide theoretical basis for the prevention and control of parasitic diseases in black goats in this county.According to the number of commercial goats less than 50,51-100,101-150,151-200 and more than 200,they are divided into five scales.Five households are selected for each scale.According to the age of black goats,each household is divided into three age groups: under 2 months old,2-12 months old and over 12 months old.Five stool samples were taken from each age group.Sheep rectal excrement samples or fresh excrement discharged from sheep were taken and labeled.The information was packed into sampling bags and stored in a 4 C refrigerator for inspection.The results of fecal worm eggs examination were as follows:(1)The parasitic infection rate of black goats in this county ranked from high to low as follows:The infection rates of Fasciola hepatica,strongylides,Schistosoma contortus,Marshall nematode,Shabert nematode,Trichinella capitalis,coccidia,elevator nematode,anteroposterior and posterior trematode were 40.17%,39.80%,34.69%,17.49%,8.50%,9.49%,4.32%,3.73% and 3.40%,respectively.Among them,the dominant species include:Fasciola hepatica,Strongyloid nematode,Haemonchus contortus,Marshall nematode and so on.In spring,Fasciola hepatica,Strongyloid nematode and Marshall nematode were mainly infected.In summer and autumn,Fasciola hepatica,strongylides,Haemonchus contortus and Marshall nematode were mainly infected.In winter,Fasciola hepatica and Strongyloid nematode were mainly infected.The infection rate and intensity in summer andautumn were higher than those in spring.In winter,the infection rate of other parasites is relatively low except for the high infection rate of Fasciola hepatica and Strongyloid nematode.Even some villages and towns have not detected some parasites.The infection rates of Fasciola hepatica,Nematode elevator and Schistosoma sinensis increased with age,while the infection rates of Angiostrongylides,Haemonchus contortus,Nematode Chabertella and Nematode trichiasis decreased with age.There was no significant difference between the ages of Coccidia and Nematode Marshall.(2)According to age group,The positive infection rate of parasites in sheep under 2months old,2-12 months old and 12 months old.A town was 68.46%,47.68%,35.83%,B town was 75.33%,54.16%,40.65%,C town was 70.22%,51.10%,39.99%,D town was70.77%,50.23%,38.12%,E town was 73.21%,52.54%,40.83,respectively.The positive rate of parasites in five town black goats decreased with age.The number of infected sheep under 2 months of age in the same town in the same season was more than that in the other two age groups.There was no significant difference in infection among different townships in the same season and age.The number of infections in summer and autumn was higher than that in spring and winter.(3)Mixed infection of sheep parasites was serious in all villages and towns.The average mixed infection rate of Wuzhen sheep was 56.2%.The mixed infection rates of sheep in Wuzhen were 61.2% in B town,58.5% in E town,57.7% in D town,56.5% in C town and 47.1% in A town.The average mixed infection rate of sheep in four seasons was74.9% in autumn,63.9% in summer,60.0% in spring and 26.1% in winter.The mixed infection rate of sheep in B town and C town in spring was higher than that in summer.The mixed infection rate of sheep in E town in summer was higher than that in autumn.The highest mixed infection rate was 78.9% in B town in autumn.Mixed infection rate decreased with the increase of sheep age,and the highest rate was 82.6% in sheep under 2months old in B town.The average mixed infection rate of sheep in five farms ranged from high to low,with D 68.1%,C 67.8%,B 50.5%,a 48.1% and E 46.6%,respectively.The mixed infection rate of D-type farms in B town,C town and D town was lower than that of C-type farms.The mixed infection rate of sheep in D-type farms in E town was the highest,which was 75.7%.Conclusion:The sheep of different ages in different scales of black goat farms in this county are infected with parasites in varying degrees.The infection rate is high,there are many kinds of infection,serious mixed infection and year-round infection.The infection rate of parasites in sheep decreases with the increase of age,and the mixed infection of commercial sheep below 200 heads per year is more serious.