Department of Poultry Science, Auburn University, Auburn, AL 36849.
White Oak Pastures, Bluffton, GA 29824.
Avian Dis. 2021 Jun;65(2):250-256. doi: 10.1637/aviandiseases-D-20-00120.
The aim of this study was to evaluate and quantify the parasitological challenge in pastured poultry production in the state of Georgia. Over the course of 1 yr, fecal samples from six turkey flocks, 10 broiler flocks, and 13 layer flocks were collected on a pastured farm in 2-wk intervals to determine counts of oocysts and nematode eggs. Average coccidia counts were 10,198 oocysts per gram of feces (OPG) in broiler flocks, 1470 OPG in layer flocks, and 695 OPG in turkey flocks. The means in broiler and turkey flocks were higher at their first week on pasture. Counts in broilers and layers were significantly higher in spring than in winter and summer. Coccidia counts in broilers were lower than published numbers in conventionally reared poultry, indicating the rotation system of the pastures might effectively reduce the infection pressure. Next-generation sequencing of PCR products showed the presence of most described spp. in broilers, layers, and turkeys. In addition, operational taxonomic units (OTUs) x, y, and z were found. The frequency of species was similar for broilers and layers, with the exception that and OTU z were more common in layers. In layer flocks, the average count of roundworm eggs per gram of feces (EPG) was 509 EPG with 80% of the samples being positive. The mean counts had no clear pattern related to age. There was an increase of EPG with the increase of temperatures during spring and summer with the peak at midfall. Worm eggs from laying hens were identified as . The seasonal differences suggest that higher temperatures might result in an increase of egg survival and sporulation in the environment.
本研究旨在评估和量化佐治亚州放牧家禽生产中的寄生虫学挑战。在为期 1 年的时间里,每隔两周从一个放牧农场的 6 个火鸡群、10 个肉鸡群和 13 个蛋鸡群中采集粪便样本,以确定卵囊和线虫卵的数量。肉鸡群的平均球虫计数为每克粪便 10198 个卵囊(OPG),蛋鸡群为 1470 OPG,火鸡群为 695 OPG。在第一批进入牧场的肉鸡和火鸡群中,这些平均值更高。肉鸡和蛋鸡在春季的数量明显高于冬季和夏季。肉鸡的球虫计数低于传统饲养家禽的公布数字,表明牧场的轮作系统可能有效地降低了感染压力。PCR 产物的下一代测序显示,肉鸡、蛋鸡和火鸡中存在大多数描述的 spp.。此外,还发现了 OTU x、y 和 z。肉鸡和蛋鸡的物种频率相似,但除了 和 OTU z 在蛋鸡中更为常见。在蛋鸡群中,每克粪便的蛔虫卵数(EPG)的平均值为 509 EPG,80%的样本呈阳性。平均计数与年龄没有明显的关系。春季和夏季气温升高时,EPG 会增加,初秋时达到峰值。从蛋鸡中分离出的蛔虫卵为 。季节性差异表明,较高的温度可能导致环境中卵的存活和孢子形成增加。