Jung Lisa, Hillemacher Sonja, Tiemann Inga, Lepke Mascha, Hinrichs Dirk
Animal Breeding Section, University of Kassel, Witzenhausen, Germany.
Institute of Agricultural Engineering, University of Bonn, Bonn, Germany.
PLoS One. 2024 Jan 26;19(1):e0297586. doi: 10.1371/journal.pone.0297586. eCollection 2024.
In commercial laying hens, keel bone damage (KBD) is a severe health and welfare problem leading to pain, reduced mobility and decreased laying performance. Flocks of all production systems and hybrid lines can be affected. KBD is a multifactorial welfare issue and, among other factors, associated with a high laying performance which negatively affects the calcium deposit in the medullary bones. Therefore, mature hens of local breeds with much lower egg production than commercial hybrids may be expected to show less or even no keel bone damage. This study evaluates (i) the prevalence of KBD in local breeds, (ii) the difference in type and level of damages, and (iii) if roosters and pullets are also affected. In total, we palpated 343 mature hens, 40 pullets, and 18 roosters of 13 different local breeds and one commercial hybrid. The animals were kept on eight different farms in free-range or floor-housing systems. Our results showed that on average 44.2% of mature hens per local breed were affected by KBD (range: 11.1%-84.7%). We found deviation of less than 1 cm in 26.9%, deviations of more than 1 cm in 6.4% and palpable fractures in 23.8% of the mature hens of local breeds. The tip was damaged in 23.6% of the mature hens. Also, pullets and roosters were affected by KBD. Finally, we found that KBD also occurs in local breeds. Therefore, we conclude that even the low laying performance of local breeds does not prevent them from the occurrence of KBD.KBD in local breeds may rather be associated with genetics (breed) as well as management and housing. Thus, breeders of local breeds should include bone health as a selection trait. Owners of local breeds should also pay attention to the condition of the keel and ought to be trained about preventive measures.
在商业产蛋母鸡中，龙骨损伤（KBD）是一个严重的健康和福利问题，会导致疼痛、行动能力下降和产蛋性能降低。所有生产系统和杂交品系的鸡群都可能受到影响。KBD是一个多因素的福利问题，除其他因素外，还与高产蛋性能有关，而高产蛋性能会对髓质骨中的钙沉积产生负面影响。因此，预计产蛋量远低于商业杂交品种的地方品种成年母鸡可能表现出较少甚至没有龙骨损伤。本研究评估了（i）地方品种中KBD的患病率，（ii）损伤类型和程度的差异，以及（iii）公鸡和小母鸡是否也受到影响。我们总共触摸检查了13个不同地方品种和一个商业杂交品种的343只成年母鸡、40只小母鸡和18只公鸡。这些动物饲养在八个不同的农场，采用自由放养或地面饲养系统。我们的结果表明，每个地方品种平均有44.2%的成年母鸡受到KBD影响（范围：11.1%-84.7%）。我们发现，地方品种成年母鸡中，26.9%的偏差小于1厘米，6.4%的偏差大于1厘米，23.8%有明显骨折。23.6%的成年母鸡龙骨尖端受损。此外，小母鸡和公鸡也受到KBD的影响。最后，我们发现KBD也发生在地方品种中。因此，我们得出结论，即使地方品种产蛋性能较低，也不能阻止它们发生KBD。地方品种的KBD可能更多地与遗传（品种）以及管理和饲养有关。因此，地方品种的育种者应将骨骼健康作为一个选择性状。地方品种的饲养者也应注意龙骨状况，并应接受预防措施方面的培训。
