Bichler L A, Nagaraja K V, Halvorson D A
Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Minnesota, St Paul 55108, USA.
Am J Vet Res. 1996 Apr;57(4):489-95.
To investigate prevalence of Salmonella enteritidis-positive eggs, excretion of the organism in fecal droppings, and infection of internal organs after oral inoculation of White Leghorn hens with S enteritidis phage type 8.
30 White Leghorn laying hens.
At 25 weeks of age, hens were each inoculated orally with 10(10) colony-forming units of S enteritidis, then were observed for 8 weeks.
Salmonella enteritidis Y-BP2 did not cause any clinical signs of disease or decrease in egg production. However, at 1 week after inoculation, 63.9% of the eggs collected from inoculated hens were culture positive for S enteritidis. The organism was isolated from the shell washings, egg shells, yolk, and albumen. A total of 592 eggs from S enteritidis-inoculated hens were examined. Of these eggs, 157 (26.5%) were positive for S enteritidis on external shell washings alone, 17 (2.9%) were positive for S enteritidis internally, and 44 (7.4%) were positive for S enteritidis externally and internally. The percentage of culture-positive eggs gradually decreased between postinoculation weeks 2 and 5, then gradually increased to a high of 76% at week B. At 3, 7, and 10 days after S enteritidis inoculation, cloacal swab specimens from 3 hens were positive for S enteritidis. Salmonella enteritidis was recovered from ovary, oviduct, liver, and cecal junction from S enteritidis-inoculated hens.
Our results indicated that birds infected with this isolate produced S enteritidis-positive eggs at high frequencies initially, that decreased over time. When S enteritidis antibody began to decrease, reaching geometric mean titer < or = 40, the frequency of S enteritidis-positive eggs increased.
研究用肠炎沙门氏菌8型噬菌体口服接种白来航蛋鸡后，肠炎沙门氏菌阳性蛋的发生率、粪便中该菌的排泄情况以及内部器官的感染情况。
30只白来航产蛋母鸡。
25周龄时，每只母鸡口服接种10¹⁰个肠炎沙门氏菌菌落形成单位，然后观察8周。
肠炎沙门氏菌Y - BP2未引起任何疾病临床症状或产蛋量下降。然而，接种后1周，从接种母鸡收集的鸡蛋中63.9%经培养肠炎沙门氏菌呈阳性。该菌可从洗蛋液、蛋壳、蛋黄和蛋清中分离出来。共检查了来自肠炎沙门氏菌接种母鸡的592枚鸡蛋。其中，仅外壳洗蛋液中肠炎沙门氏菌呈阳性的有157枚（26.5%），内部肠炎沙门氏菌呈阳性的有17枚（2.9%），外壳洗蛋液和内部均呈阳性的有44枚（7.4%）。培养阳性蛋的百分比在接种后第2周和第5周逐渐下降，然后在第8周逐渐上升至76%的高位。肠炎沙门氏菌接种后第3、7和10天，3只母鸡的泄殖腔拭子标本肠炎沙门氏菌呈阳性。从肠炎沙门氏菌接种母鸡的卵巢、输卵管、肝脏和盲肠连接处分离出肠炎沙门氏菌。
我们的结果表明，感染该分离株的鸡最初产生肠炎沙门氏菌阳性蛋的频率较高，随后随时间下降。当肠炎沙门氏菌抗体开始下降，几何平均滴度≤40时，肠炎沙门氏菌阳性蛋的频率增加。
