A study was conducted to determine differences between Histomonas meleagridis-infected and control pullets based on disease signs, hen growth, and egg production and quality. Ross 708SF females were weighed and then placed in pens on the day of hatch (92 chicks/pen). At 25 D, 4 pens were infected with H. meleagridis in the cloaca, whereas 4 pens were control. At 5, 10, and 20 D after inoculation, 5 birds per pen (2 birds per pen at 20 D) were subjectively scored for blackhead disease. Birds were feed restricted based on BW and/or egg production. Individual BW were collected at 3, 5, 13, 15, 20, and 64 wk. Egg production was recorded at 24-63 wk. Egg quality was measured at 30, 34, 39, 42, and 56 wk and included shell and vitelline membrane strength, shell thickness, egg weight, and Haugh units. Hatchability was measured at 27, 37, and 60 wk and fertility at 27 and 37 wk. Treatment effects were determined by JMP Pro 14 using GLM with means separated using the Student t test (P ≤ 0.05). Cecal lesions were apparent on 5, 10, and 20 D and liver lesions on 10 and 20 D for the infected birds. The control had no histomoniasis lesions. Flock uniformity differed on wk 13 and 20 (P = 0.04; 0.04). Infected birds weighed less at 64 wk (P = 0.002). The onset of lay was not delayed. Infected birds produced more eggs during 1 period (P = 0.02). The infected birds produced heavier eggs at 30 wk (P = 0.04), eggs with a stronger and thicker shell at 42 wk (P = 0.05, 0.03), and eggs with a stronger vitelline membrane at 56 wk (P = 0.049). Hatchability and fertility did not differ (P > 0.05). H. meleagridis was observed in the infected birds' cecal samples at trial termination. This study indicates early infection with H. meleagridis has limited effects on pullet egg production and quality.

中文翻译：

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早疫病对肉鸡种鸡的生长以及产蛋量和质量的影响有限。

进行了一项研究，以根据疾病迹象，母鸡生长以及产蛋量和质量确定肉食性组织感染的小鸡与对照小鸡之间的差异。称重Ross 708SF雌性，然后在孵化当天将其放在围栏中（92只小鸡/只）。在25 D时，泄殖腔中感染了4支笔，而4支是对照。接种后第5、10和20天，每头有5只鸟（在20天时每头有2只鸟）主观评分为黑头病。根据体重和/或产蛋量限制家禽的采食。分别在3、5、13、15、20和64周收集BW。产蛋量记录在24-63周。在30、34、39、42和56 wk时测得的鸡蛋质量包括蛋壳和卵黄膜的强度，蛋壳厚度，蛋重和Haugh单位。孵化率在27、37，60周和27周和37周的受精率。通过使用GLM的JMP Pro 14确定治疗效果，并使用Student t检验（P≤0.05）分离均值。对于受感染的鸟类，盲肠病变在5、10和20 D时明显，肝病变在10和20 D时明显。对照组无组织病病变。第13周和第20周的羊群均匀度有所不同（P = 0.04; 0.04）。受感染的家禽体重减轻了64 wk（P = 0.002）。外行发作没有延迟。受感染的鸟类在1个时期内产卵量更多（P = 0.02）。被感染的禽类在30周时产卵较重（P = 0.04），在42周时产卵壳更坚固，更厚（P = 0.05，0.03），在56周龄产卵卵黄膜更强（P = 0.049）。孵化率和繁殖力没有差异（P> 0.05）。在试验终止时，在受感染鸟类的盲肠样品中观察到了H. meleagridis。