Oke O E, Onagbesan O M
Animal Physiology Department, Federal University of Agriculture Abeokuta, Nigeria.
Centre of Excellence in Avian Sciences, University of Lome, Togo.
Heliyon. 2024 Jul 18;10(14):e34780. doi: 10.1016/j.heliyon.2024.e34780. eCollection 2024 Jul 30.
Despite the plethora of studies on the impacts of access to runs on chickens, there is a paucity of information on the welfare and behavioural repertoire of hens raised in the deep litter houses with or without access to legume- or grass-based pasture. Therefore, this study aimed to evaluate the impact of access to grass or legume pastures by laying hens on behaviour, physiological responses and bacterial load. The study was conducted to evaluate the influence of exposure of egg-type chickens to runs on grass or legume pastures on their welfare and behaviours. The study involved the use of 240 ISA brown pullets from 12 weeks of age and and lasted for 48 weeks. The treatments were deep litter housing with grass-based pasture run (PG), deep litter housing with legume-based pasture run (PL) and deep litter housing without runs (LD) having 80 pullets with four replicates of twenty birds each. Behavioural observations of the hens in each pen were made at 52 weeks of age and tonic immobility was assessed by making the birds lie on their back with their head resting in a U-shaped wooden cradle. The measurements of the respiratory rate and rectal temperature of the hens were assessed at 1:00 p.m. at different laying phases. The gastrointestinal and egg bacterial counts were conducted at 60 weeks of age. Results revealed that the proportion of time spent eating was highest (p < 0.05) in the deep litter housing system, while the legume and grass pasture were similar. The hens spent most of their time standing and eating in the three treatments. However, the time spent standing in PL and PG was similar but significantly higher (p < 0.05) than in LD. Results on tonic immobility duration showed that the time spent by the hens in LD during the reaction was significantly longer than those of the PL and PG in the first, second and third phases of the experiments. However, the time spent by the hens in PL and PG was similar. The rectal temperatures of PL and PG birds were comparable and higher than those of LD during the second phase. On the other hand, there was no difference in the respiratory rate. Plasma triiodothyronine (T) of the hens did not follow a consistent pattern. The bacterial count in the large intestine in LD and PL was similar but significantly (P < 0.05) higher than that of the PG. It was concluded that access to pasture influenced the behaviours of hens and that tonic immobility duration was shorter in the hens on the pasture, suggesting that access to pasture favoured hens' welfare.
尽管有大量关于鸡舍对鸡影响的研究，但对于在有或没有豆科植物或草地牧场的厚垫草鸡舍中饲养的母鸡的福利和行为模式的信息却很少。因此，本研究旨在评估蛋鸡接触草地或豆科植物牧场对其行为、生理反应和细菌负荷的影响。该研究旨在评估蛋鸡接触草地或豆科植物牧场对其福利和行为的影响。该研究使用了240只12周龄的ISA褐壳小母鸡，持续了48周。处理方式为厚垫草鸡舍搭配草地牧场（PG）、厚垫草鸡舍搭配豆科植物牧场（PL）以及无牧场的厚垫草鸡舍（LD），每组有80只小母鸡，每组20只，共四个重复。在52周龄时对每个鸡舍中的母鸡进行行为观察，并通过让鸡仰卧，头部置于U形木制支架中来评估强直静止。在不同产蛋阶段的下午1点评估母鸡的呼吸频率和直肠温度。在60周龄时进行胃肠道和鸡蛋细菌计数。结果显示，在厚垫草鸡舍系统中进食时间比例最高（p<0.05），而豆科植物和草地牧场的情况相似。在三种处理方式下，母鸡大部分时间都在站立和进食。然而，在PL和PG中站立时间相似，但显著高于LD（p<0.05）。强直静止持续时间的结果表明，在实验的第一、第二和第三阶段，LD组母鸡在反应期间花费的时间明显长于PL和PG组。然而，PL和PG组母鸡花费的时间相似。在第二阶段，PL和PG组鸡的直肠温度相当且高于LD组。另一方面，呼吸频率没有差异。母鸡的血浆三碘甲状腺原氨酸（T）没有呈现出一致的模式。LD和PL组大肠中的细菌计数相似，但显著高于PG组（P<0.05）。研究得出结论，接触牧场会影响母鸡的行为，并且牧场中的母鸡强直静止持续时间较短，这表明接触牧场有利于母鸡的福利。
