Muneer M A, Newman J A, Halvorson D A, Sivanandan V, Coon C N
Department of Pathobiology, College of Veterinary Medicine, University of Minnesota, St. Paul 55108.
Avian Dis. 1987 Oct-Dec;31(4):820-8.
Twenty-four-week-old white leghorn layers were inoculated subcutaneously with a killed Newcastle-infectious bronchitis (Massachusetts type) virus (MIBV) vaccine. The birds were challenged 194 days later intraocularly with Arkansas strain of infectious bronchitis virus (AIBV). The challenged hens laid significantly (P less than 0.005) fewer eggs than the unchallenged layers, and the eggs laid by the challenged groups weighed significantly less (P less than 0.001) than those laid by the unchallenged groups. Further, the internal quality (Haugh units) and shell quality of eggs laid by the challenged hens were significantly (P less than 0.005) inferior to the quality of eggs from unchallenged hens, and the challenged hens laid more soft-shelled, misshapen, and small-sized eggs than the unchallenged hens. The Arkansas serum hemagglutination-inhibition (AIBV-HI) titers of challenged birds increased continuously through 29 days post-challenge. The MIBV hemagglutination-inhibition (MIBV-HI) titers of killed-MIBV-vaccinated birds decreased during the same period. The study indicates that killed MIBV vaccine offered no protection to birds exposed to AIBV. The same vaccine was quite effective against a homologous (MIBV) virus challenge.
给24周龄的白来航蛋鸡皮下接种灭活的新城疫-传染性支气管炎（马萨诸塞型）病毒（MIBV）疫苗。194天后，用传染性支气管炎病毒阿肯色毒株（AIBV）对这些鸡进行眼内攻毒。攻毒后的母鸡产蛋量显著低于未攻毒的蛋鸡（P<0.005），攻毒组所产蛋的重量也显著低于未攻毒组（P<0.001）。此外，攻毒母鸡所产蛋的内部品质（哈氏单位）和蛋壳品质显著低于未攻毒母鸡（P<0.005），且攻毒母鸡产出的软壳蛋、畸形蛋和小蛋比未攻毒母鸡更多。攻毒鸡的阿肯色血清血凝抑制（AIBV-HI）效价在攻毒后29天内持续升高。在此期间，接种灭活MIBV疫苗的鸡的MIBV血凝抑制（MIBV-HI）效价下降。该研究表明，灭活的MIBV疫苗对暴露于AIBV的鸡没有保护作用。同一疫苗对同源（MIBV）病毒攻毒相当有效。
