Price Kayla R, Freeman Megan, Van-Heerden Kobus, Barta John R
Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada N1G 2W1.
Ceva Vetech, 131 Malcolm Road, Guelph, ON, Canada N1K 1A8.
Vet Parasitol. 2015 Mar 15;208(3-4):242-5. doi: 10.1016/j.vetpar.2015.01.009. Epub 2015 Jan 17.
Hatching, processing and transportation result in inevitable delays before chicks are placed into brooding and receive their first feed and drinking water after hatching. To determine if delayed access to feed for different durations following live Eimeria vaccination affected initial shedding of vaccine progeny, replacement layer chicks (480, Lohmann-LSL Lite) aged approximately 6h after hatch were administered a commercial live Eimeria vaccine. Vaccinated chicks were divided randomly into groups and were provided access to feed immediately (0 h) or after a delay of 6, 12, or 24 h (4 treatments × 6 replicates per treatment × 20 pullets per replicate). All pullets were provided drinking water immediately following vaccination. Fecal oocysts shed per gram of feces for each cage replicate was determined daily from 4 to 9 days post inoculation. Chicks provided feed immediately had peak oocyst shedding at 5 days post-inoculation but delayed access to feed for 24h was associated with a 2 days delay in peak oocyst shedding to 7 days post-inoculation. Chicks with delays in access to feed of intermediate duration (i.e. 6 or 12h) had peak oocyst shedding at 6 days post-inoculation. Overall oocyst shedding was not affected. Live Eimeria vaccination success may be measured by evaluating initial shedding of oocysts at some pre-established time after vaccine application, usually by a single fecal collection conducted at 5, 6 or 7 days post-inoculation. Recognizing that withholding feed following live Eimeria vaccination shifts the time of the resultant peak oocyst shedding complicates the assessment of vaccine application; if delayed access to feed is not taken into account, it is possible that false conclusions could be drawn regarding the relative success of vaccine administration.
孵化、处理和运输过程不可避免地会导致雏鸡在放入育雏舍并在孵化后首次进食和饮水之前出现延迟。为了确定在活球虫疫苗接种后不同时长延迟喂食是否会影响疫苗后代的初始排出情况，对孵化后约6小时的480只罗曼-LSL Lite型替代蛋鸡雏鸡接种了一种商业化的活球虫疫苗。将接种疫苗的雏鸡随机分组，并在接种后立即（0小时）或延迟6、12或24小时后提供饲料（4种处理×每种处理6个重复×每个重复20只小母鸡）。所有小母鸡在接种疫苗后立即提供饮水。在接种后第4至9天，每天测定每个笼子重复样本每克粪便中排出的粪便卵囊数。接种后立即提供饲料的雏鸡在接种后第5天出现卵囊排出高峰，但延迟24小时喂食会使卵囊排出高峰延迟2天至接种后第7天。延迟中间时长（即6或12小时）喂食的雏鸡在接种后第6天出现卵囊排出高峰。总体卵囊排出情况未受影响。活球虫疫苗接种的成功与否可通过在疫苗接种后某个预先设定的时间评估卵囊的初始排出情况来衡量，通常是在接种后第5、6或7天进行单次粪便采集。认识到在活球虫疫苗接种后 withhold feed（此处原文有误，推测应为withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed，即 withholding feed 意为“ withholding feed。。。导致的卵囊排出高峰时间发生变化，这使得疫苗接种效果的评估变得复杂；如果不考虑延迟喂食的情况，就有可能在疫苗接种相对成功与否的问题上得出错误结论。 （注：原文中多次出现重复且混乱的内容，推测可能是格式或录入问题，已尽力按合理逻辑翻译）
