Cerquetti M C, Gherardi M M
Centro de Estudios Farmacológicos y Botánicos (CEFYBO-CONICET), Serrano 669 1414, Buenos Aires, Argentina.
Vet Microbiol. 2000 Sep 25;76(2):185-92. doi: 10.1016/s0378-1135(00)00235-2.
Chickens were immunized orally with 10(9)cfu of the temperature-sensitive (T(s)) mutant E/1/3 of Salmonella enteritidis at 1, 2, 3 and 7 days of age. The animals were challenged with wild-type strains of Salmonella of different serotypes 7 or 14 days following immunization. Chickens receiving multiple oral doses of the vaccine strain showed no signs of disease. Immunized animals shed the vaccine strain for at least 2 weeks after the last inoculation; on the other hand, colonization by the attenuated mutant of internal organs such as spleen and liver was limited. Early exposure of the immunized animals to the virulent bacteria resulted in a reduced cecal colonization by the pathogen. Visceral invasion by the wild-type strain of S. enteritidis or S. gallinarum was drastically diminished in birds challenged 14 days after immunization. Significant differences in the number of these Salmonella were found in the cecal contents, spleen and liver of immunized birds compared with the control animals. In addition, cecal colonization by the virulent strain was reduced in birds challenged with S. typhimurium. These results demonstrate that immunization of newly hatched chickens with live attenuated T(s) mutant E/1/3 of S. enteritidis is safe and reduces Salmonella shedding.
在1、2、3和7日龄时，用10⁹cfu的肠炎沙门氏菌温度敏感（Ts）突变株E/1/3对雏鸡进行口服免疫。在免疫后7或14天，用不同血清型的野生型沙门氏菌菌株对动物进行攻毒。接受多剂口服疫苗株的雏鸡未表现出疾病迹象。免疫动物在最后一次接种后至少2周排出疫苗株；另一方面，减毒突变株在脾脏和肝脏等内脏器官的定植受到限制。免疫动物早期接触有毒细菌导致病原体在盲肠的定植减少。在免疫14天后攻毒的禽类中，肠炎沙门氏菌或鸡沙门氏菌野生型菌株的内脏侵袭显著减少。与对照动物相比，在免疫禽类的盲肠内容物、脾脏和肝脏中发现这些沙门氏菌的数量存在显著差异。此外，用鼠伤寒沙门氏菌攻毒的禽类中，有毒菌株在盲肠的定植减少。这些结果表明，用肠炎沙门氏菌活减毒Ts突变株E/1/3对新孵化的雏鸡进行免疫是安全的，并可减少沙门氏菌的排出。
