饲养密度和鸡笼局部遮光对肉种鸡产蛋期行为与福利的影响

用行为录像记录分析仪(The Observer Video-Pro，Noldus)观察和测定肉种鸡在产蛋期行为的变化。对两种不同饲养密度(或者空间供给：单鸡笼组，1 600 cm²/只；双鸡笼组，800 cm²/只)及鸡笼后部局部遮光与对照组进行比较实验结果表明，单鸡笼组肉种鸡的转身、挠头等行为均显著多于双鸡笼组，而展翅行为显著少于双鸡笼组；遮光组的肉种鸡采食行为显著多于未遮光组；遮光单鸡笼组肉种鸡，其产蛋行为趋向选择暗光区域。研究提示，虽然密度对蛋鸡行为的效应大于遮光的效应，但是局部遮光能够在一定程度上增加盒式笼养鸡的环境丰富度，降低密度增大引起的拥挤效应，可能缓解其较差的福利状态。     

不同遮光处理对川西柳叶菜部分形态、生长和生理指标的影响

以自然光照为对照,对轻度、中度和重度遮光条件下(遮光率分别为24%、48%和72%)川西柳叶菜( Epilobium fangii C. J. Chen et al.)的部分形态、生长和生理指标进行比较分析。分析结果显示：遮光处理对川西柳叶菜的MDA含量无显著影响,对叶长、花冠宽、叶干质量分配比例以及叶绿素a( Chla)、叶绿素b( Chlb)和类胡萝卜素(Car)含量及Chla/Chlb值有显著影响(P<0.05),对其余指标有极显著影响(P<0.01)。与对照相比,3个遮光处理组的单株根数、株高、主茎长和基径总体上显著下降,根长在轻度和中度遮光条件下略升高、在重度遮光条件下显著升高;3个遮光处理组的单株叶片数和叶长总体上显著下降,叶宽在轻度和中度遮光条件下略下降、在重度遮光条件下显著升高,叶厚在轻度遮光条件下显著升高、在中度遮光条件下略下降、在重度遮光条件下显著下降;3个遮光处理组的花柄长、花管长和花冠高显著升高,单株开花数在轻度遮光条件下略下降、在中度遮光条件下显著升高、在重度遮光条件下显著下降,花冠宽在轻度和中度遮光条件下略升高、在重度遮光条件下显著升高。与对照相比,3个遮光处理组的全株干质量和茎干质量分配比例均显著下降;根干质量分配比例和根冠比在轻度遮光条件下显著升高、在中度和重度遮光条件下略下降;地上部干质量分配比例在轻度遮光条件下显著下降、在中度和重度遮光条件下略升高;叶干质量分配比例在轻度和中度遮光条件下略下降、在重度遮光条件下略升高。在轻度和中度遮光条件下,叶片的Chla、Chlb和Car含量基本上显著高于对照,Chla/Chlb值分别略低于或显著低于对照;而在重度遮光条件下这4个指标均略高于对照。与对照相比,轻度和中度遮光条件下叶片的H2 O2含量和SOD活性略升高,MDA含量和总抗氧化能力略下降;总酚含量在轻度遮光条件下略下降、在中度遮光条件下略升高;重度遮光条件下这5个指标均显著升高。随着遮光程度的增强,川西柳叶菜的单株根数、株高、主茎长、基径和叶厚逐渐下降,而叶宽、全株干质量、叶干质量分配比例、H2 O2含量、SOD活性和总酚含量逐渐升高;其中,在中度遮光条件下,其单株开花数、花柄长、花管长、花冠高、花冠宽和花干质量分配比例最高。结果表明：在遮光条件下,川西柳叶菜可在形态、生长和生理上调整生长策略,完成发育过程;并且,中度遮光有利于其生殖分配,提高其观赏价值。     

流速对光棘球海胆行为和生长的影响

海胆在海藻床生态系统结构和功能调控中发挥重要作用。深入理解流速对海胆摄食和生长的影响具有重要的生态学研究价值。研究了长时间(49 d)不同流速(2 cm/s, 10 cm/s和20 cm/s)对光棘球海胆幼胆(Mesocentrotus nudus,壳径：约20 mm)摄食行为、摄食量和生长的影响，以评估不同流速下，海胆摄食行为和生长的差异。实验结果表明，流速对光棘球海胆的存活无显著影响，但显著影响其生长。2 cm/s下海胆的壳径和体重显著大于10和20 cm/s。在实验开始后的第2周和第3周，2 cm/s下海胆的体重和壳径已显著高于20 cm/s。流速显著影响光棘球海胆的摄食量(P<0.001)和觅食行为(20 cm/s,P=0.004),但口器咬合行为未受显著影响(P=0.113)。管足附着时间在流速为10 cm/s和20 cm/s下显著长于其在2 cm/s。同样的，相较于2 cm/s(P=0.02)和10 cm/s(P=0.03),20 cm/s的流速可显著削弱光棘球海胆的翻正行为。综上，高流速(20 cm/s)通过影响海胆管足活动削弱其觅食行为(而非摄食行为),进而降低其...     

行距和密度配置对黔南山地烤烟经济性状的影响

采用裂区设计,结合经济效果(ECI)指数法和偏(Eta)²效应量分析法,明确行距、种植密度及其互作效应对烤烟经济性状的影响。结果表明,行距110 cm (R_1.1)处理的产值和ECI均高于行距100 cm (R_1.0)处理。单叶重、上等烟比例随着种植密度增大而降低,即种植密度1.5万株·hm^–2处理(D_1.5)显著高于种植密度2.1万株·hm^–2处理(D_2.1);产量和产值则随着种植密度增大而提高,D_2.1显著高于D_1.5;ECI随着种植密度的增大先增后降,种植密度1.8万株·hm^–2处理(D_1.8)显著高于其他2处理。在行距和种植密度互作中,R_1.1D_1.5与R_1.0D_1.5处理的单叶重均显著高于R_1.0D_2.1与R...     

配偶数增加对布氏田鼠社会行为的影响

为研究配偶数量对布氏田鼠 (Microtusbrandti)社会行为的影响 ,设置了 6组处理方法 :对照组 1♂+1♀配对组 ,只增加雌性配偶的 1♂ +2♀处理组和 1♂ +3♀处理组 ,只增加雄性配偶的 2♂ +1♀处理组和 3♂ +1♀处理组以及同时增加雌雄配偶的 2♂ +2♀处理组。每个处理各设 10个重复。记录各实验组中布氏田鼠在观察箱内 (两个大小为 37cm× 2 7cm× 17cm的有机塑料箱合并而成 ) 10min内发生的非对抗行为频次和对抗行为频次。结果表明 :与对照组相比 ,其它各组布氏田鼠的非对抗行为频次都明显降低 ,而对抗行为频次都明显增加。有效性比和密度与布氏田鼠社会行为的相关性研究表明 ,配偶数增加主要通过密度的改变来影响布氏田鼠的社会行为 ,配偶数增加引起密度的升高 ,密度的升高导致布氏田鼠社群内非对抗行为显著减少 ,对抗行为显著增加 ,从而引起布氏田鼠社群关系的紧张 ,加大了社群的竞争强度.     

宝天曼国家级自然保护区落叶阔叶林密度制约效应对树木存活的影响

密度制约对物种共存起着重要作用。随着密度制约效应研究的深入, 亲缘关系较近的物种间表现出的密度制约效应逐渐被人们认识。本研究基于2009和2014年对宝天曼1 ha落叶阔叶林样地的2次调查数据, 利用广义线性混合模型分析了重要值排名前11位的物种不同邻域尺度的密度制约效应对不同径级(小径级(1 cm ≤ DBH < 5 cm)、中径级(5 cm ≤ DBH < 10 cm)、大径级(DBH ≥ 10 cm))目标个体存活的影响。研究表明: (1) 5年间样地中DBH ≥ 1 cm的所有个体的年均死亡率和增员率分别为5.85%和0.27%; (2)有5个物种的个体存活率与同种邻体个体数及同种邻体胸高断面积显著负相关; (3)小径级个体的存活在5 m的邻域范围内受同种密度制约和谱系密度制约的影响都很显著; 中径级个体在3个尺度上受到的密度制约和谱系密度制约的影响都不大; 大径级个体在7.5 m、10 m邻域范围内受谱系密度制约影响显著。结果表明, 同种密度制约和谱系密度制约效应对宝天曼落叶阔叶林不同生长阶段的树木个体影响不同。     

遮光对不同基因型玉米光合特性的影响

采用盆栽试验,研究了遮光对4个基因型玉米光合特性的影响.结果表明:4个基因型玉米叶片的光饱和点、净光合速率(Pn)、电子传递速率(ETR)、光系统Ⅱ最大光化学效率(Fv/Fm)和实际光化学效率(ΦPSⅡ)均受光强的影响.遮光降低了玉米的光饱和点,苗期遮光处理豫玉2号和丹玉13分别在光量子通量密度(PFD)为1400μmol·m-2·s-1和1100μmol·m-2·s-1时达到饱和.遮光还降低了玉米的Pn、ETR、Fv/Fm和ΦPSⅡ,但不同基因型玉米表现不同,豫玉2号和掖单22的下降幅度较小,而丹玉13和掖单6号的下降幅度较大.     

花生幼苗光合特性对弱光的响应

在苗期用黑色遮阳网对丰花1号和丰花2号进行不同遮光处理(不遮光,遮光27%、43%和77%),研究了苗期遮光及恢复对花生叶片光合特性的影响.结果表明： 遮光后,随遮光程度增强,叶片叶绿素含量显著增加,实际光化学效率(Ф_PSⅡ)和最大光化学效率(F_v/F_m)升高,叶绿素a/b和净光合速率(P_n)降低.恢复自然光照后1 d,在高光强下测定时,随前期遮光程度增强,P_n、气孔导度(G_s)下降,细胞间隙CO₂浓度(C_i)升高;在低光强下测定时,P_n显著升高,G_s和C_i下降;低光强与高光强下测定的P_n比值显著升高;恢复自然光照后,随前期遮光程度增强,光补偿点、光饱和点、CO₂补偿点、CO₂饱和点和羧化效率显著降低,表观量子效率显著升高.恢复自然光照后,P_n、Ф_PSⅡ和F_v/F_m先迅速下降,3～5 d后逐渐回升;恢复15 d后,遮光27%处理的各项指标恢复到对照水平,其他处理的恢复程度则因遮光程度和品种而异.丰花1号各处理叶绿素含量、P_n、Ф_PSⅡ均高于丰花2号.苗期遮光提高了花生利用弱光的能力,降低了其利用强光的能力.     

5-氨基酮戊酸光动力疗法体外抑制断发毛癣菌肉芽肿株增殖研究

目的探讨5-氨基酮戊酸光动力疗法(5-Aminolevulinic acid photodynamic therapy,ALA-PDT)对体外培养的断发毛癣菌肉芽肿株的杀伤效应。方法将临床Majocchi肉芽肿患者皮损分离培养出的断发毛癣菌肉芽肿株,在马铃薯葡萄糖琼脂培养基上活化后制备菌悬液,与5mmol/L ALA共孵育后荧光显微镜观察原卟啉PpⅨ(ProtoporphyrinⅨ,PpⅨ)产生情况。实验分对照组、单药组、单光组和ALA-PDT组。对照组无处理。ALA-PDT组断发毛癣菌与5 mmol/L ALA共孵育6h后,采用功率密度为40mW/cm2的633nm红光以不同能量密度(50、100、150、175、200J/cm2)照射。单药组断发毛癣菌与5mmol/L ALA共孵育6h,不照光。单光组无ALA共孵育,只给予200J/cm2红光照射。通过数码相机拍摄照片及菌浓度评估ALA-PDT对断发毛癣菌肉芽肿株生长的抑制效应。结果荧光显微镜下可见明显砖红色荧光物质PpⅨ产生,当照光能量密度为175、200J/cm2时,照片显示菌落生长明显受限,数量减少,菌浓度计数分别为(0.53±0.058)×105 CFU/mL、(0.13±0.057)×105 CFU/mL,明显低于对照组、单药组、单光组及其他低能量密度ALA-PDT组(P0.05)。结论 ALA-PDT对断发毛癣菌肉芽肿株有明确的杀伤效应,可为临床ALA-PDT治疗皮肤癣菌感染提供理论依据。     

分株比例对异质光环境下美丽箬竹克隆系统光合生理的影响

分株数量或生物量比例差异会明显影响克隆系统对资源异质性环境的生态适应性, 地下茎木质化、连接稳固的竹类植物在生长过程中相连克隆分株通常会生活在异质光环境中, 但其叶片光合生理特性对异质光环境的响应及其分株比例效应则未见报道。该研究以地下茎相连的美丽箬竹(Indocalamus decorus)克隆系统为实验材料, 设置2个遮光率(分别为50% ± 5%和75% ± 5%)和3个分株比例(遮光与未遮光分株比例分别为1:3、2:2、3:1)处理, 分株数量为4株。分别测定了遮光处理后30、90、150天遮光和未遮光分株叶片光响应特征、气体交换参数、光合色素含量, 分析了异质光环境下美丽箬竹光合生理的变化规律。结果显示: 分株比例对美丽箬竹光合生理有显著影响, 且其与遮光、处理时间交互作用显著。美丽箬竹克隆系统遮光分株比例越大, 即遮光相对分株数量越多, 其表观量子效率(AQE)、光饱和点、最大净光合速率(P_{n max})、净光合速率(P_n)、气孔导度(G_s)、蒸腾速率(T_r)、水分利用效率越大, 光补偿点、暗呼吸速率越小, 其光合效率越高, 光能利用能力越强, 而与之相连的未遮光分株则相反; 随遮光分株比例的增大, 遮光分株叶片叶绿素a、叶绿素b含量呈先升高而后下降的变化趋势, 类胡萝卜素(Car)含量则持续下降, 而与之相连的未遮光分株叶片光合色素含量则呈下降趋势; 遮光率提高, 相同分株比例美丽箬竹克隆系统遮光分株叶片AQE、P_{n max}、P_n、G_s、胞间CO₂浓度(C_i)和光合色素含量总体升高, 而与之相连的未遮光分株叶片P_{n max}、C_i以及Car含量则总体下降。研究结果表明异质光环境下, 遮光分株光合效率和弱光利用能力明显增强, 而未遮光分株则相反, 克隆系统内分株间发生了明显的克隆分工, 且2:2、3:1分株比例克隆系统较1:3分株比例对异质光环境具有更好的适应能力。美丽箬竹克隆系统可通过差异性调节分株光合生理特性和光合色素含量, 提高遮光分株光能利用和光合效率来适应异质光环境, 以提高克隆系统的适合度。     

Behaviour of laboratory mice in different housing conditions when allowed to self-administer an anxiolytic

Standard cages prevent mice from performing several natural behaviours for which they are motivated. As a consequence, abnormal behaviours sometimes develop and mice often spend long periods inactive. To improve welfare, cages are sometimes furnished with items such as nesting material, shelters and running wheels. We have previously reported that when allowed to self-administer an anxiolytic, mice in furnished cages consume less anxiolytic than mice in standard cages. This paper presents the results of behaviour studies of the mice in the same experiment. Female C57BL/6J mice (3 per cage) were housed in Standard (n = 10), Unpredictable (n = 10) or Furnished (n = 6) cages. Unpredictable cages were identical to Standard cages, but were exposed to unpredictable events two to three times a week. Furnished cages were double the size of Standard cages and contained nesting material, nest box, tubes, chew blocks and a running wheel. During three consecutive periods, mice had access to only water (control), water or an anxiolytic solution on a daily alternating schedule (forced consumption), and finally, both water and anxiolytic (self-administration). Behaviour was analysed from video recordings taken during the dark phase. The housing type affected behaviour both under the control and the self-administration conditions. Overall, mice in Furnished cages spent less time resting and performing bar-related behaviours and more time on exploratory/locomotory behaviours. Mice in Furnished cages also performed less bar-circling stereotypies than mice in Standard cages. The Unpredictable treatment did not significantly affect behaviour compared to mice in the Standard conditions. There was an overall effect of anxiolytic availability on rest-related behaviours and on exploration-locomotion behaviours, in that mice rested more and spent less time on exploration and locomotion when they were able to self-administer the anxiolytic.     

The effect of alternative feeding strategies on the feeding motivation of broiler breeder pullets

Due to genetic selection for fast growth and high breast meat yield, commercial strains of broiler chickens and broiler breeders are predisposed to high feed intake; however, feeding broiler breeders ad libitum impairs their health and reproductive performance. Broiler breeders are feed-restricted throughout rearing to maintain health and performance, yet feed restriction results in hunger, feeding frustration and lack of satiety. The objective of this study was to examine the effect of alternative feeding strategies, including feed additives (separately or combined) and a fixed non-daily feeding schedule, on the feeding motivation and welfare of broiler breeders during rearing. At 3 weeks of age, 180 Ross 308 breeder pullets were allocated to 90 cages and fed with one of five isocaloric treatments: (1) daily control diet (control), (2) daily calcium propionate diet (CaP), (3) daily soybean hull diet (SBH), (4) daily alternative diet (alternative: CaP + SBH) and (5) 4/3 control diet (four on-feed days and three non-consecutive off-feed days per week). The CaP diet included calcium propionate at 1.4% from 3 to 6 weeks of age, and at 3.2% from 7 to 12 weeks of age, and the SBH diet contained soybean hulls included at 40%. The alternative diet included both soybean hulls and calcium propionate at the same inclusion rate as the SBH and CaP diets, respectively. Pullets were weighed and scored for feather coverage every week. A feed intake test was conducted at 3, 4, 8, 10 and 11 weeks of age for 10 min during on- and off-feed days. At 12 weeks of age, feather samples were analysed for fault bars. Data were analysed using linear mixed regression models, with cage nested in the models and age as a repeated measure. At 4 weeks of age, pullets fed soybean hull-enriched diets (SBH and alternative diets) and those on the 4/3 schedule had lower feed intake than control pullets (P = 0.02). Feathers from pullets fed the SBH diet had fewer fault bars than those fed the CaP diet (P = 0.04). The results indicated that the inclusion of soybean hulls (alone or combined with calcium propionate) and a 4/3 feeding schedule can reduce feeding motivation of broiler breeders during early rearing.     

Animal Welfare Issues in the Poultry Industry: Is There a Lesson to Be Learned?

Many of the conditions in which poultry live and the procedures to which they are subjected compromise their welfare. This article describes these welfare problems in the hope that they may serve as warnings to the rest of animal agriculture, which then might take steps to avoid the same pitfalls. The article discusses poultry welfare problems under the headings of battery cages for laying hens, forced molting, disposal of spent laying hens, fast growth problems in meat poultry, catching and transportation, food restriction of broiler breeders, hyperaggressiveness in broiler breeder males, elective surgeries, and water-bath stunning.     

On-farm assessment of laying hen welfare: a comparison of one environment-based and two animal-based methods

Methods available to assess animal welfare at farm level are based on a range of welfare parameters, which can be divided into two categories, environment-based and animal-based parameters. The first category describes features of the environment and management, which can be considered prerequisites for welfare. The second category records animals’ responses to that particular environment and management more directly. Objective of this study was to validate a mainly environment-based method, the animal needs index (ANI), with animal-based methods: behavioural observations and feather condition scores (FCS). The study was conducted on 20 commercial laying hen farms, 10 farms with battery cages and 10 farms with deep litter systems. During a 1-day visit on each farm, ANI was assessed, FCS was scored, and behavioural observations were performed. Instantaneous scan sampling and continuous focal sampling were used to assess the time spent on different behaviours and the occurrence of event behaviours. Data from behavioural observations and FCS were reduced with principal factor analysis. This resulted in two factors for each method. Significant positive correlations were found between ANI, on the one hand, and ‘movement’ and ‘comfort’, two factors from behavioural observations, on the other hand. A significant negative correlation was found between ANI and ‘wing damage’ (from FCS). The results of this study show that ANI is valid and sensitive enough to show differences in animal welfare between housing systems, whereas differences in welfare within housing systems cannot be shown. In conclusion, ANI is an appropriate method for assessment of laying hen welfare on a large number of farms with different housing systems.     

Effects of a commercial broiler enrichment programme with or without natural light on behaviour and other welfare indicators

Commercial broiler production systems based on market initiatives to improve animal welfare beyond minimum legal requirements have emerged in several European countries. A common factor in the ‘higher welfare’ indoor systems is the application of environmental enrichment, with or without natural light, to promote locomotor activity and natural behaviours of the broiler chickens. In the current study, we evaluated the effects of a commercial enrichment programme for fast-growing indoor-housed broiler chickens, with or without natural light entering the broiler house. Enrichment materials were selected in relation to perceived minimal hygiene risk and ease of cleaning in between production cycles. Selected enrichments were a combination of wood shavings bales (1.5 bale/1000 chickens), round metal perches (2.7 m/1000 chickens) and metal chains as pecking objects (1/1000 chickens). Three treatments were studied: control (C) without enrichment and natural light, enriched (E) with enrichments as previously defined but without natural light and enriched plus natural light (EL) with enrichments as previously defined and natural light entrance. The experiment was carried out during five subsequent production cycles on one commercial broiler farm with three identical houses. EL could only be assigned to the middle house that was equipped with roof windows (light entrance area: 3% of floor space). C and E were in the two outer houses (alternated in between production cycles). Behaviour was observed during daytime at days 25 and 39 of age by scan sampling. Lameness, footpad dermatitis, hock burn, cleanliness and injuries were scored at the same ages, in addition to the response of the chickens to a novel object. Results showed that the treatments only affected broiler behaviour. E flocks showed significantly more resting as compared with EL and C. EL flocks showed significantly more walking, exploration and foraging behaviour as compared with E and C. Thus, broiler activity was highest in the EL treatment and lowest in the E treatment, with the C treatment in between. No treatment effects were found on the other welfare indicators and only a few tendencies for treatment effects were found for the novel object test, with E birds tending to be more reluctant to approach the object as compared with EL and C birds. We concluded that providing environmental enrichment and natural light-stimulated activity and natural behaviours in broiler chickens, whereas providing enrichment only seemed to have the opposite effect as compared with control flocks without enrichment.     

Furnished cages for laying hens: study of the effects of group size and litter provision on laying location, zootechnical performance and egg quality

The furnished cage is a new housing system for layers. A current trend in furnished cage design is to increase group size and replace the litter box with a mat provided with litter. An experiment was set up to determine the effects of group size and litter provision on laying performance and egg quality of beak-trimmed ISA Brown hens housed in large furnished cages with more than 12 hens. Six treatments, each of 18 furnished cages (768 cm(2)/hen including nest and litter area) were compared in a 3 × 2 experimental trial: three group sizes (S20 (20 hens per cage), S40 (40) and S60 (60)), with or without feed as litter distributed on the mat of the litter area. The provision of facilities per hen was equal in all treatments. Mortality, laying rate, mean egg weight, feed intake and feed conversion ratio were unaffected by group size over the 53-week laying period, and performance exceeded the ISA production standards. The overall percentage of eggs laid in the nest exceeded 95% except that it was slightly lower in group S20 (92.0% ± 6.4% v. S40: 96.0% ± 3.3% and S60: 96.2% ± 2.7%) leading to a higher proportion of dirty eggs (S20: 1.6% ± 2.2%, S40: 1.4% ± 1.5%, S60: 1.0% ± 1.0%). At 66 to 70 weeks, eggs laid outside the nest had a slightly higher count of mesophilic bacteria on the eggshell (5.0 log CFU/egg ± 0.4) than those laid in the nest (4.8 log CFU/egg ± 0.5) but no difference in contamination was observed between group sizes. Litter provision had no effect on mortality, egg weight or egg quality traits except for a higher proportion of broken eggs in cages with litter (5.3% ± 6.2% v. 4.6% ± 5.7%). Providing hens with feed for litter was associated with a higher laying rate (97.3% ± 3.2% v. 94.8% ± 4.4% at 23 weeks) and an apparent improvement in feed efficiency at the beginning of the laying period (feed conversion ratio based on feed consumption at the trough: 2.18 ± 0.06 with litter v. 2.28 ± 0.09 without litter at 25 weeks). The results of this study showed that a high level of productivity and good egg quality could be obtained in large furnished cages. Further research is needed to assess the impact on hens' welfare and performance of using more economically competitive substrates than feed for litter.     

Effect of cage enrichment on the daily use of running wheels by Syrian hamsters

Institutional animal care committees may one day require for the welfare of captive hamsters more floor space and the introduction of tunnels and toys. As hamsters are popular animal subjects in chronobiological research, and as clock phase is usually measured through running wheel activity, it is important to determine what effect cage enrichment might have on daily wheel use. Here the daily number of wheel revolutions, the daily duration of the running activity phase, the phase relationship between lights-off and onset of running activity, and the free-running period of circadian activity rhythms were measured in Syrian hamsters, Mesocricetus auratus, housed in single cages or in multiple cages linked by tunnels and supplied with commercial wooden toys. Free-running periodicity was not affected by cage enrichment. In multiple-cage systems, there were fewer daily revolutions, shorter wheel-running activity phases, and delayed running activity onsets. These effects, however, were small as compared to interindividual and week-to-week variation. They were statistically significant only under a light:dark cycle, not in constant darkness, and only when interindividual variation was eliminated through a paired design or when the number of cages was increased to five (the maximum tested). Daily wheel use is thus affected by cage enrichment, but only slightly.     

The effects of a reduced balanced protein diet on litter moisture,pododermatitis and feather condition of female broiler breeders over three generations

Protein content reduction in broiler breeder diets has been increasingly investigated. However, broiler breeders reared on low protein diets are characterized by a deterioration of the feather condition. Furthermore, polydipsia induced by controlled feed intake increases litter moisture and as a consequence pododermatitis. This project aimed to study the litter moisture, pododermatitis and feather condition of breeders fed with a 25% reduced balanced protein (RP) diet during the rearing and laying period over three successive generations. The experiment started with two treatments for the F0 generation: control (C) group fed with standard C diets and RP group fed with RP diets. The female F0-progeny of each treatment was divided into the two dietary treatments as well, resulting in four treatments for the F1 generation: C/C, C/RP, RP/C and RP/RP (breeder feed in F0/F1 generation). The RP diet fed breeders received on average 10% more feed than C diet fed breeders to achieve the same target BW. The female F1-progeny of each treatment were all fed with C diets which resulted in four treatments for the F2 generation: C/C/C, C/RP/C, RP/C/C and RP/RP/C (breeder feed in F0/F1/F2 generation). Litter moisture, footpad and hock dermatitis were recorded at regular intervals throughout the experimental period in all three generations. For the F0 and F1 generation, the pens of breeders receiving C diets had significantly higher litter moisture than the RP diets fed groups (P<0.05), resulting in an elevated footpad dermatitis occurrence (FDO) (P<0.05). No difference was found in the F2 generation. The feather condition was scored during the laying period for each generation. F0 and F1 breeders reared on the RP diets had poorer feather condition than those receiving the C diets (P<0.05). The C/RP breeders had a significantly poorer feather condition than RP/RP breeders (P<0.05). For the F2 generation, RP/RP/C breeders had a significantly better feather condition compared with the other three groups (P<0.05). The RP/C/C breeders were significantly better feathered than C/C/C breeders (P<0.05). In conclusion, providing RP diets to broiler breeders improved litter condition and hence reduced FDO whereas impaired feather condition. Furthermore, positive transgenerational effects of the maternal RP diets on the feather condition may be inferred, hence potentially altering the welfare status.     

Exposing broiler eggs to green,red and white light during incubation

Previous work has shown that exposing broiler eggs to white light during incubation can improve hatchability and post-hatch animal welfare. It was hypothesized that due to how different wavelengths of light can affect avian physiology differently, and how pigmented eggshells filter light that different monochromatic wavelengths would have differential effects on hatchability and post-hatch animal welfare indicators. To determine, we incubated chicken eggs (n=6912) under either no light (dark), green light, red light or white light; the light level was 250 lux. White and red light were observed to increase hatch of fertile (P<0.05) over dark and green light incubated eggs. White, red and green light exposure during incubation improved (P<0.05) the proportion of non-defect chicks over dark incubated eggs. Post-hatch 45-day weight and feed conversion was not affected by light exposure of any wavelength (P>0.05). Fear response of during isolation and tonic immobility was reduced (P<0.05) in broilers incubated under white or red light when compared with either green or dark broilers. Broilers incubated with white or red light had lower (P<0.05) composite asymmetry scores and higher (P<0.05) humoral immunity titers than dark incubated broilers, however, green light broilers did not differ (P>0.05) from dark incubated broilers. All light incubated broilers had lower (P<0.05) plasma corticosterone and higher (P<0.05) plasma serotonin concentrations than dark incubated broilers. These results indicate that white light and red light that is a component of it are possibly the key spectrum to improving hatchability and lower fear and stress susceptibility, whereas green light is not as effective. Incubating broiler eggs under these spectrums could be used to improve hatchery efficiency and post-hatch animal welfare at the same time.     

Gregarious nesting in relation to floor eggs in broiler breeders

Gregarious nesting has often been observed in laying hens, where hens prefer to visit a nest already occupied by other hens over empty nests. This may result in overcrowding of the nests which is considered a welfare issue and, moreover, can increase the economic issue of floor eggs. This study aimed to describe gregarious nesting and spatial behavior in broiler breeders and how this relates to genetic background, fearfulness and mating behavior. Five commercially available genetic lines of broiler breeders were housed in 21 pens of 550 females and 50 males (six pens for lines 1 and 2, five pens for line 3 and two pens for lines 4 and 5) during the ages 20–60 weeks. Every 10 weeks, the plumage condition and wounds were assessed of 50 random hens per pen. Avoidance distance and novel object tests were performed to assess fearfulness at four time points. Distribution of eggs over nests was observed for 6 weeks at the onset of egg production at 26 weeks of age, and use of space was recorded at four time points, while (floor) egg production was noted daily per pen. We found differences between genetic lines over time in plumage condition and prevalence of wounds. Fear of humans was highest at the earliest age tested and did not correlate with general fearfulness as assessed by the novel object test. The distribution of eggs over nests was related to genetic background and was more uneven at the earliest age compared to later ages, and a more uneven distribution was correlated with an increased percentage of floor eggs. Distribution of birds over the litter area differed between the genetic lines, and less use of the litter area was correlated with an increased fear of humans and presence of wounds, suggesting an association with aggressive mating behavior. This difference in distribution of the birds could also explain the correlation between increased presence of wounds and decreased percentage of floor eggs. It is concluded that broiler breeders do show gregarious nesting, which is affected by genetic background. Both increased gregarious nesting and wounds are related to increased floor egg percentage, which should be studied further in broiler breeder research. Genetic selection for even use of the available nests and of the litter and slatted area would therefore support both broiler breeder welfare and performance.