Maurer V, Amsler Z, Perler E, Heckendorn F
Research Institute of Organic Agriculture (FiBL), Ackerstrasse, CH-5070 Frick, Switzerland.
Vet Parasitol. 2009 May 12;161(3-4):255-60. doi: 10.1016/j.vetpar.2009.01.020. Epub 2009 Feb 3.
The aim of this study carried out in 6 commercial layer houses was to examine the effect of litter management on water content, helminth egg count and litter infectiousness with the intestinal nematodes Ascaridia galli, Heterakis gallinarum, and Capillaria spp. Three types of litter management were established in each layer house in parallel: in compartment A, litter was left undisturbed, in compartment B, wet litter was replaced and in compartment C, new litter material was added weekly. Dry matter (DM) contents of the litter and parasitological parameters (helminth egg concentration in litter samples, faecal egg counts (FECs) in the permanent layer flocks, helminth prevalence and burdens in two series of tracer animals) were determined every 4 weeks during the first 32 weeks of one laying period. DM contents of the litter varied in a broad range (48-95%); 8 weeks after onset of the study, there were significant differences between sites (P<0.001) but not between management regimes. A. galli/H. gallinarum eggs were isolated from 91% of the litter samples, whereas eggs of Capillaria spp. were only extracted from 13% of the samples. Egg concentrations in litter remained at a similar level during the observation period. Neither management regime reduced helminth egg concentrations in the litter compared to the unmanaged regime. Laying hens started excreting helminth eggs 8 weeks after introduction to the layer house. In treatment C (litter added) FECs were lower than in the unmanaged treatment A in weeks 8 (P<0.0001), 20, and 28 (both P<0.1). There was no correlation between the concentration of helminth eggs in the litter and the FECs of the layer flocks. The prevalence of A. galli in tracer animals was lower (<10%) than the prevalences of H. gallinarum (68-80%) and Capillaria spp. (30-58%). Prevalences and H. gallinarum burdens did not differ significantly between management regimes. Although high helminth egg concentrations were found in litter, the prevalence and worm burdens in tracer animals were low compared to a similar study with tracers kept in poultry runs. The reasons for this may be that poultry litter negatively affects viability and infectiousness of helminth eggs. However, underlying mechanisms need to be clarified.
本研究在6个商业蛋鸡舍中开展，目的是考察垫料管理对水分含量、蠕虫虫卵计数以及垫料被鸡蛔虫、鸡异刺线虫和毛细线虫等肠道线虫感染性的影响。在每个蛋鸡舍中并行建立了三种垫料管理方式：在A区，垫料保持原状；在B区，更换潮湿的垫料；在C区，每周添加新的垫料。在一个产蛋期的前32周内，每4周测定一次垫料的干物质（DM）含量和寄生虫学参数（垫料样本中的蠕虫虫卵浓度、常驻蛋鸡群的粪便虫卵计数（FEC）、两批示踪动物体内蠕虫的感染率和感染负荷）。垫料的DM含量变化范围很大（48 - 95%）；研究开始8周后，不同区域之间存在显著差异（P<0.001），但不同管理方式之间无显著差异。91%的垫料样本中分离出了鸡蛔虫/鸡异刺线虫的虫卵，而毛细线虫的虫卵仅从13%的样本中提取到。在观察期内，垫料中的虫卵浓度保持在相似水平。与未管理的方式相比，两种管理方式均未降低垫料中蠕虫虫卵的浓度。蛋鸡引入蛋鸡舍8周后开始排出蠕虫虫卵。在第8周（P<0.0001）、第20周和第28周（P均<0.1），处理C（添加垫料）的FEC低于未管理的处理A。垫料中蠕虫虫卵的浓度与蛋鸡群的FEC之间无相关性。示踪动物中鸡蛔虫的感染率（<10%）低于鸡异刺线虫（68 - 80%）和毛细线虫（30 - 58%）的感染率。不同管理方式下鸡异刺线虫的感染率和感染负荷无显著差异。尽管垫料中发现了高浓度的蠕虫虫卵，但与在鸡舍中饲养的示踪动物的类似研究相比，示踪动物的感染率和蠕虫负荷较低。其原因可能是家禽垫料对蠕虫虫卵的活力和感染性有负面影响。然而，潜在机制仍需阐明。
