Kasabov R, Nikolova M, Obreshkov K, Mentov V
Vet Med Nauki. 1976;13(3):53-8.
Studies were carried out to establish the effectiveness of the immunization of broilers against Marek's disease using a Bulgarian vaccine produced with strain C3-1 of a turkey herpes virus. The experiments were done under the conditions of an industrial poultry dressing combine with a total of 52,450 day-old hybrid birds vaccinated at the rate of 1000 plaque-forming units (PFU), 39,450 birds vaccinated with 500 PFU each, and 91,564 unvaccinated control birds. After the 60-63-day fattening period was over the average value of the mortality rate was 2.17 per cent and 2.48 per cent in the vaccinated birds and the controls, respectively. The vaccinated groups of birds showed also a comparatively higher weight gain--by 73 g, on an average, recorded prior to slaughter--as against the control groups. No differences were found in these indices between the groups immunized with 1000 and 500 PFU. In a laboratory test with 255 birds divided into four groups immunized with 100, 500, 250, PFU and controls, challenged in the third week with a pathogenic herpes virus it was found that up to the 6th month the first two groups developed Marek's disease as accounted by 1.65 per cent of the birds, while those vaccinated at the rate of 250 PFU were not properly protected, showing a higher morbidity rate--9.23 per cent. It is concluded that the Bulgarian vaccine--strain C3-1--confers solid immunity in a dose of 500 PFU, the vaccination of broilers being economically profitable.
开展了多项研究，以确定使用由火鸡疱疹病毒C3 - 1株生产的保加利亚疫苗对肉鸡进行马立克氏病免疫接种的效果。实验在一家工业家禽屠宰联合企业的条件下进行，共有52450只一日龄杂交鸡，其中1000只以每只1000个蚀斑形成单位（PFU）的剂量进行接种，39450只每只接种500 PFU，91564只未接种作为对照。在60 - 63天的育肥期结束后，接种疫苗的鸡和对照鸡的平均死亡率分别为2.17%和2.48%。接种疫苗的鸡群在屠宰前平均体重增加也相对较高，比对照组平均重73克。接种1000 PFU和500 PFU的组在这些指标上没有差异。在一项实验室试验中，将255只鸡分为四组，分别接种100、500、250 PFU并设对照组，在第三周用致病性疱疹病毒进行攻击，结果发现直到第6个月，前两组有1.65%的鸡患马立克氏病，而接种250 PFU的组没有得到充分保护，发病率较高，为9.23%。得出的结论是，保加利亚疫苗——C3 - 1株——以500 PFU的剂量可提供可靠的免疫力，对肉鸡进行免疫接种在经济上是有利可图的。
