MSD Animal Health Innovation GmbH, Zur Propstei, 55270, Schwabenheim, Germany.
Praxis Dr. Pöppel, Drubbelstrasse 2, 33119, Delbrück, Germany.
Parasit Vectors. 2021 Mar 31;14(1):181. doi: 10.1186/s13071-021-04685-7.
Poultry red mite (PRM) (Dermanyssus gallinae) infestations are a cause of anaemia, impaired productivity and stress-related behaviours linked to reduced hen welfare. A study investigated the potential health, welfare and productivity benefits following fluralaner treatment to eliminate PRM from infested hens.
A PRM-infested layer house was selected on a free-range farm (5400 hens) and an aviary farm (42,400 hens). Fluralaner (Exzolt; 0.5 mg/kg body weight) was administered twice, 7 days apart (Weeks 0 and 1), via drinking water. Mite populations were monitored by traps. Cameras recorded nighttime hen behaviours weekly, pre- and post-treatment. On the free-range farm, daytime behaviours were also recorded weekly. For pre- and post-treatment corticosterone assessments, eggs were randomly collected on both farms, and blood samples were collected from 50 randomly selected aviary farm hens. Production parameters were assessed using farm records.
Throughout the post-treatment period, fluralaner efficacy against PRM was > 99% on both farms. On the aviary and free-range farms, treatment was followed by significant nighttime increases in the proportion of resting hens (P < 0.0001; P = 0.0175, respectively). Significant post-treatment versus pre-treatment nighttime reductions were observed in head shaking (aviary, P < 0.0001; free-range P = 0.0233) and preening (P = 0.0032; P = 0.0018) and on the aviary farm in bouts of body shaking (P = 0.0108), vertical wing shaking (P = 0.0002), head scratching (P = 0.0335), and gentle feather pecking (P < 0.0001). On the free-range farm there were significant daytime reductions in head scratching (P < 0.0001), head shaking (P = 0.0492) and preening (P = 0.0012). Relative to standard production parameters, no differences were detected on the aviary farm, but on the free-range farm the laying rate decline with increasing age was less than expected and the increase in egg weight greater than expected. Post-treatment increases in egg and plasma corticosterone were suggestive of stress factors in addition to mite infestation. Red blood cell counts and haematocrit increased following treatment.
Fluralaner treatment eliminated mite challenge, leading to improved hen welfare and health, based on reductions in stress-related behaviours and restoration of the anaemia-inducing effects of mite blood feeding.
家禽红螨（PRM）（Dermanyssus gallinae）感染是导致贫血、生产性能下降和与应激相关的行为的原因，这些行为与母鸡福利下降有关。一项研究调查了在感染鸡群中使用氟虫腈治疗根除 PRM 后对健康、福利和生产性能的潜在益处。
在一个自由放养农场（5400 只母鸡）和一个鸟舍农场（42400 只母鸡）中选择了一个被 PRM 感染的鸡舍。通过饮用水给氟虫腈（Exzolt；0.5mg/kg 体重）两次，间隔 7 天（第 0 周和第 1 周）。通过诱捕器监测螨虫数量。摄像机每周记录夜间母鸡行为，治疗前和治疗后。在自由放养农场，还每周记录白天的行为。在治疗前和治疗后的皮质酮评估中，从两个农场随机收集鸡蛋，并从 50 只随机选择的鸟舍农场母鸡中采集血液样本。使用农场记录评估生产参数。
在整个治疗后期间，氟虫腈对两种农场的 PRM 的疗效均超过 99%。在鸟舍和自由放养农场，治疗后夜间休息母鸡的比例显著增加（P<0.0001；P=0.0175）。在治疗后夜间，鸟舍农场的摇头（P<0.0001）和自由放养农场的理羽（P=0.0233）显著减少，鸟舍农场的摇头（P<0.0001）和自由放养农场的理羽（P=0.0018）显著减少，鸟舍农场的身体摇晃（P=0.0108）、垂直翅膀摇晃（P=0.0002）、头部刮擦（P=0.0335）和温和的啄羽（P<0.0001）也显著减少。在自由放养农场，头部刮擦（P<0.0001）、摇头（P=0.0492）和理羽（P=0.0012）的白天次数显著减少。与标准生产参数相比，鸟舍农场没有差异，但在自由放养农场，随着年龄的增长，产蛋率的下降低于预期，而蛋重的增加高于预期。治疗后，鸡蛋和血浆皮质酮的增加表明除了螨虫感染外，还存在应激因素。治疗后红细胞计数和红细胞压积增加。
氟虫腈治疗根除了螨虫的挑战，通过减少与应激相关的行为和恢复螨虫吸血对贫血的影响，改善了母鸡的福利和健康。
