Department of Animal Science, Livestock Production Systems, Georg August University, Göttingen, 37075 Göttingen, Germany.
Vet Parasitol. 2011 Mar 10;176(2-3):250-7. doi: 10.1016/j.vetpar.2010.11.007. Epub 2010 Nov 18.
Groups of Lohmann Brown (LB) and Lohmann Selected Leghorn (LSL) hens were reared under helminth-free conditions and kept afterwards together in a free range system. Mortality rate, body weight development, laying performance and faecal egg counts (FEC) were recorded during a 12 month laying period. At the end of the laying period, 246 LSL and 197 LB hens were necropsied and worms counted following the World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) guidelines. In addition adult Heterakis gallinarum and Ascaridia galli were sexed and measured for length. Significant (P<0.01) differences were observed in mortality rates between LSL and LB animals (12.9 vs. 5.7%). LSL hens showed significantly (P<0.05) higher FEC when compared with LB hens at almost all dates of monitoring. Almost all animals became infected with at least one helminth species. The most prevalent species were H. gallinarum, Capillaria spp. and A. galli. LB hens showed a significantly (P<0.05) higher average number of adult H. gallinarum, Capillaria spp. and tapeworms when compared with LSL animals. However, number of adult A. galli was in tendency lower in these animals. In total, LB had a significantly (P<0.05) higher worm burden than LSL (192.3 vs. 94.3). The estimated heritabilities for total worm burden were 0.23 (SE±0.12) in LSL and 0.75 (SE±0.21) in LB, respectively. The number of all different helminth species were positively correlated. The sex ratio of H. gallinarum and A. galli and the average worm lengths were not significantly (P>0.05) different between the genotypes. There was no significant phenotypic correlation between body weight and worm burden in LSL, whereas it was the case in LB (r=0.17, P<0.05). Based on the estimated heritabilities it is possible to select for helminth resistance in both genotypes.
洛曼棕鸡（LB）和洛曼海兰灰鸡（LSL）的鸡群在无寄生虫环境下饲养，然后一起在自由放养系统中饲养。在 12 个月的产蛋期内记录死亡率、体重发育、产蛋性能和粪便卵囊计数（FEC）。产蛋期末，对 246 只 LSL 和 197 只 LB 母鸡进行剖检，并按照世界兽医寄生虫学协会（W.A.A.V.P.）的指南计算蠕虫数量。此外，对成年盲肠螺旋线虫和鸡蛔虫进行性别鉴定和长度测量。LSL 和 LB 动物的死亡率存在显著差异（P<0.01）（12.9%比 5.7%）。与 LB 母鸡相比，LSL 母鸡的 FEC 在几乎所有监测日期都显著更高（P<0.05）。几乎所有动物都感染了至少一种寄生虫。最常见的物种是盲肠螺旋线虫、毛细线虫和鸡蛔虫。与 LSL 动物相比，LB 母鸡的成年盲肠螺旋线虫、毛细线虫和绦虫数量显著更高（P<0.05）。然而，这些动物的成年鸡蛔虫数量较低。总的来说，LB 的蠕虫负担显著高于 LSL（192.3 比 94.3）。LSL 的总蠕虫负担的估计遗传力为 0.23（SE±0.12），LB 为 0.75（SE±0.21）。所有不同的寄生虫物种数量呈正相关。盲肠螺旋线虫和鸡蛔虫的性别比例以及平均蠕虫长度在两种基因型之间没有显著差异（P>0.05）。在 LSL 中，体重和蠕虫负担之间没有显著的表型相关性，而在 LB 中则存在这种相关性（r=0.17，P<0.05）。基于估计的遗传力，可以在两种基因型中选择对寄生虫的抗性。
