Layer Housing Research Articles

Greenhouse Gas Emissions from Three Cage Layer Housing Systems.

Simple SummaryGreenhouse gas (GHG) emissions were measured from three different cage layer housing systems. A comparative study was conducted to identify the housing system with the least impact on the environment. The results showed that liquid manure from deep-pit housing systems produces greater emissions of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) than natural and forced dried manure from belt housing systems. The influencing factors appeared to be the manure removal frequency and the dry matter content of the manure.Agriculture accounts for 10 to 12% of the World’s total greenhouse gas (GHG) emissions. Manure management alone is responsible for 13% of GHG emissions from the agricultural sector. During the last decade, Québec’s egg production systems have shifted from deep-pit housing systems to manure belt housing systems. The objective of this study was to measure and compare carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) emissions from three different cage layer housing systems: a deep liquid manure pit and a manure belt with natural or forced air drying. Deep liquid manure pit housing systems consist of “A” frame layer cages located over a closed pit containing the hens’ droppings to which water is added to facilitate removal by pumping. Manure belt techniques imply that manure drops on a belt beneath each row of battery cages where it is either dried naturally or by forced air until it is removed. The experiment was replicated with 360 hens reared into twelve independent bench-scale rooms during eight weeks (19–27 weeks of age). The natural and forced air manure belt systems reduced CO2 (28.2 and 28.7 kg yr−1 hen−1, respectively), CH4 (25.3 and 27.7 g yr−1 hen−1, respectively) and N2O (2.60 and 2.48 g yr−1 hen−1, respectively) emissions by about 21, 16 and 9% in comparison with the deep-pit technique (36.0 kg CO2 yr−1 hen−1, 31.6 g CH4 yr−1 hen−1 and 2.78 g N2O yr−1 hen−1). The shift to manure belt systems needs to be encouraged since this housing system significantly decreases the production of GHG.

Litter lipid content affects dustbathing behavior in laying hens

Within the European Union, the provision of dustbathing material in layer housing systems will be compulsory beginning in 2012. In cage systems, food particles are mainly used as litter material and are provided on scratching mats by an automatic transporting system. However, because dustbathing is a means for hens to remove stale lipids from their plumage, lipid content of a substrate may be an important asset with regard to its adequacy. This study analyzes dustbathing behavior as affected by lipid content of feed used as litter material. A total of 72 laying hens of 2 genotypes (Lohmann Selected Leghorn, Lohmann Brown) were kept in 12 compartments (6 hens each). Compartments were equipped with a plastic grid floor (G) and additionally contained 3 different dustbathing trays (each 1,000 cm(2)/hen) holding low-lipid (0.82%; L), normal-lipid (4.2%; N), and high-lipid (15.7%; H) food particles. The experiment began at 20 wk of life, and video recordings were done at wk 23, 26, and 29. Number of dustbaths, time spent dustbathing, average dustbath duration, foraging, and single behaviors within dustbaths were analyzed during the light period over 2 d in each observation week. Dustbaths occurred most frequently in the L compared with the N, H, and G treatments (all P < 0.001). Total time spent dustbathing was longest in the L treatment compared with the N and H treatments (P < 0.001). No difference in the average duration of single dustbaths was found between the L, N, and H treatments. However, when dustbath interruptions (less than 10 min) were excluded, the duration of single dustbaths was longer in the H compared with the L (P = 0.009) and N (P = 0.024) treatments. Foraging was most frequently observed in the N compared with the L, H, and G treatments (all P < 0.001). More body wing shakes occurred in the L compared with the N treatment, and the number of vertical wing shakes was higher in the N compared with the H treatment (all P ≤ 0.05). Our results showed that preference for a dustbathing substrate increased with decreasing lipid content, implying that food particles may not be a suitable dustbathing substrate.

A Comparison of Humoral Immune Function in Response to a Killed Newcastle’s Vaccine Challenge in Caged Vs. Free-range Hy-line Brown Layers

The relationship between immune function and disease risk may be greatly influenced by an organism’s response to chronic stressors including those that are environmentally induced. Measurements of stress-induced immune alterations have previously been made in poultry species by utilizing hematological and immunological indices. To ascertain the effects of alternative layer housing management methods on humoral immune function, Hy-line Brown hens housed on range (n = 15) or in battery style cages (n = 20) were inoculated with a killed Newcastle's vaccine. Blood serum samples were taken prior to injection and for three consecutive weeks following injection to assess antibody production. Antibody production was significantly higher in caged hens in comparison to free-range hens at pre-injection (1.69±0.70 vs. 0.069±0.069) (p<0.0001) and post-injection week one (2.26±0.77 vs. 0.145±0.25) (p<0.0001), week two (8.00±2.98 vs. 4.38±2.94) (p<0.001) and week 3 (9.24±2.56 vs. 6.69±3.86) (p<0.05). Additionally, caged hens exhibited a significantly higher level (p<0.0001) of total antibody production (5.30±0.23) throughout the immune challenge compared to free-range hens (2.82±0.26). Caged hens exhibited significantly higher H:L ratios (2.34±0.86 vs. 1.75±0.57) (p<0.05) during post-injection week 2 which correlated with the greatest difference in antibody production observed between the two groups of hens. This data indicated that environmental management methods utilized in layer hen production may influence both levels of humoral immune function and heterophil:lymphocyte ratios.

Effects of housing system and age of laying hens on egg performance in fresh pasta production: pasta cooking behaviour

Very few studies concern the effects of layer housing systems and age on egg technological properties. Thus the aim of this work was to study the influence of these two factors on egg performance in fresh pasta production, focusing on pasta cooking behaviour. Samples of pasta subjected to analysis were prepared with eggs laid by Hy-Line Brown hens (from 27 to 68 weeks old) housed in cage, barn and organic systems. Higher average values of weight increase and matter loss during pasta cooking were observed for samples prepared with eggs laid by older hens. Such cooking behaviour indicated the development of a weaker pasta protein network, resulting from a decrease in the quantity of albumen protein and an increase in fat content, which is due to the reduction in albumen/yolk ratio during hen aging. The housing system had a significant effect only on matter loss in cooking water, but differences between samples were so small as to be unlikely perceived by consumers. Both hen age and housing system significantly affected pasta cooking behaviour, but the greatest effect was exerted by the hen age.

Poultry farming in the cold, arid Himalayan region of India

In the cold, arid Himalayan region of India, where the altitude is 3048–3658 m above mean sea level (MSL) and the temperature ranges from +35°C to -35°C, poultry farming is very difficult. Poultry farming in Leh-Ladakh has been a venture that has generally taken a back seat in this cold, arid region for a number of reasons. In this region, the Buddhist community makes up most of the population, and, because of their largely vegetarian lifestyle; they generally avoid killing animals in principal. Another reason is the lack of availability of any specific high yielding variety of layer or broiler breed in this high altitude region. Typically, the existing local poultry breeds exhibit very poor egg and meat production. Further factors which have influenced poultry production are the unavailability of poultry feed and the existence of harsh climatic conditions. The status of poultry rearing in this region is not encouraging, with the current total population of poultry birds limited to just a few thousand. There are many constraints contributing to this, including limited availability of feed, lack of subsidies, religious sentiments, lack of availability of suitable germ plasm, limited poultry feed ingredients, and poor knowledge regarding poultry farming. Furthermore, the housing of poultry is difficult in this cold, arid climate. Maintaining the optimum temperature of 25 to 35°C inside brooder and 15 to 20°C inside grower and layer housing requires modifications to the design of traditional poultry housing. The different types of housing available for use in this area are above- ground mud walled poly sheds, semi-underground mud or stone walled houses, trombay wall sheds and solar poultry houses. Fertility and hatchability are therefore the main problems in this area. The problems of poultry farming in high altitude and their solutions have been addressed in this paper.

Effects of housing conditions during the rearing and laying period on adrenal reactivity, immune response and heterophil to lymphocyte (H/L) ratios in laying hens

This study was conducted to evaluate the effect of early rearing conditions on physiological, haematological and immunological responses relevant to adaptation and long-term stress in white Leghorn hens with intact beaks housed in furnished cages (FC) or conventional cages (CC) during the laying period. Pullets were cage reared (CR) or litter floor reared (FR). From 16 to 76 weeks of age, hens were housed in FC (eight hens per cage) or in CC (three hens per cage). As measures of long-term stress at the end of the laying period, adrenal reactivity was quantified by assessing corticosterone responses to adrenocorticotropin challenge, and immune response was assessed by measuring antibody responses after immunization with sheep red blood cells (SRBC) and keyhole limpet haemocyanin (KLH). Heterophil to lymphocyte (H/L) ratio was employed as an indicator of stress. Rearing conditions significantly affected anti-SRBC titres (P < 0.0001) and tended to affect H/L ratios (P = 0.07), with the highest values found in FR hens. Layer housing affected H/L ratio (P < 0.01); the highest ratio was found in FR birds housed in FC during the laying period. This study shows that early rearing environment affects immunological indicators that are widely used to assess stress in laying hens. However, while results on H/L ratio indicated that FR birds experienced more stress particularly when they were housed in FC during the laying period, the immune responses to SRBC in FR hens was improved, indicating the opposite. This contradiction suggests that the effects on immune response may have been associated with pathogenic load due to environmental complexity in FR and FC hens rather than stress due to rearing system or housing system per se.

Providing laying hens with perches: fulfilling behavioural needs but causing injury?

1. The EU laying hen directive, which bans standard battery cages from 2012, has implications for animal welfare, particularly since housing laying hens in extensive systems, while increasing natural behaviour and improving bone strength, is associated with a greater level of bone fractures, predominantly of the keel bone, compared to birds housed in cages. 2. The aetiology and welfare consequences of keel and other bone fractures are not well understood and could have important implications for housing system designs. While proposed alterations to layer housing are based on the desire to fulfil behavioural needs and increase bone strength, there appears to have been little consideration of the effect of system on potential injury. 3. In addition, there are variations in how the directive is interpreted. For example, egg producers housing hens in extensive systems in Scotland and Northern Ireland must provide hens with aerial perches, whereas in England and Wales they do not. Aerial perches may be implicated in bone fracture injuries. 4. This paper reviews the prevalence of bone fractures in the egg-laying sector of the poultry industry and the literature on perches. It also explores how bone fractures may be occurring. 5. We propose some means of reducing bone fracture, namely through improved housing designs and genetic selection.

Effects of Housing System and Age on Early Stage Egg Production and Quality in Commercial Laying Hens

2grazing area per bird). The effect of age on measured traits was investigated with 4 weeks intervals. Four replicates containing each 40 birds were designed for both of free-range and cage systems. The egg production and cracked egg percentage, daily feed intake and feed consumption per produced egg were different between housing systems. Regardless the housing system; daily feed intake and feed intake per produced egg increased, while egg production, cracked egg percentage decreased by the age of layer. Interactions between layer age and housing systems were found significant for egg production, cracked egg percentage, albumen index, albumen pH and haugh unit parameters. Yolk color (P<0.03) was considerably darker and shell thickness was significantly greater (P<0.01) in free-range eggs while albumen pH was significantly higher (P<0.01) in cage group. We concluded that egg production and quality traits were significantly affected by the housing system furthermore, maintaining external and internal egg quality parameters in constant state especially in free-range system appeared to be difficult.

Effects of Stocking Density and Group Size on Heat and Moisture Production of Laying Hens under Thermoneutral and Heat-Challenging Conditions

Current and relevant heat and moisture production data for laying hens are necessary for sizing and operating ventilation systems for commercial layer housing. Different stocking densities are being adopted in cage layer facilities, but there is a lack of information concerning the potential impacts of these changes on environmental control. A study was conducted with 24 groups of 48 hens (39 to 46 weeks old) to compare heat and moisture production, via indirect calorimetry, for four different stocking densities (348, 387, 465, or 581 cm2 hen-1; 54, 60, 72, or 90 in.2 hen-1) and two group sizes (8 or 16 hens per cage). Data were collected under thermoneutral (24°C or 76°F) and heat-challenging conditions (32°C or 90°F and 35°C or 95°F). No notable differences in heat and moisture production were observed among the treatments under the experimental conditions. Room-level 24 h time-weighted mean sensible heat production, latent heat production or moisture production, and total heat production, respectively, were found to be 2.8 to 3.1 W kg-1, 3.5 to 3.7 W kg-1, and 6.4 to 6.6 W kg-1 at 24°C; 0.7 to 1.0 W kg-1, 4.9 to 5.2 W kg-1, and 5.6 to 6.1 W kg-1 at 32°C; and -1.0 to -0.4 W kg-1, 5.9 to 6.5 W kg-1, and 5.4 to 5.7 W kg-1 at 35°C. These results imply that for existing laying hen houses, reducing stocking density, and thus flock size, will reduce the heat and moisture generated within the houses. This may lead to difficulties in maintaining desired temperatures without compromising air quality during cold weather, but reducing stocking density may offer benefits for heat stress prevention and relief during hot weather.

Estimativa das condições de conforto térmico para avicultura de postura usando a teoria dos conjuntos Fuzzy

Neste trabalho, foi utilizada uma ferramenta matemática promissora na análise de sistemas e/ou processos, particularmente na área de produção animal. Essa ferramenta é a desenvolvida segundo a abordagem da teoria dos Conjuntos Fuzzy e, neste caso específico, permitiu a análise da composição das variáveis climáticas independentes, como temperatura de bulbo seco e umidade relativa do ar, que influenciam na variável dependente denominada conforto térmico das aves. Foi realizada a construção de regras baseadas na intuição humana, segundo o conhecimento de especialistas da área, a partir do que é possível simular cenários distintos para o suporte à decisão de construção de galpões para abrigo a animais. Neste trabalho, foi estimado o conforto térmico para alojamento de aves poedeiras em produção. Os resultados foram analisados, usando-se o ambiente de computação científica MATLAB 6.5, o que pode ser realizado iterativamente a cada cenário gerado. Com base nos resultados obtidos, pode-se analisar as condições de conforto para distintas composições das variáveis de entrada.

Effects of housing system (outdoor vs cages) and age of laying hens on egg characteristics

1. Effects of two housing systems (cages vs outdoor) on external and internal egg characteristics were investigated. 2. In total 785 eggs from three different lines in cages and 268 eggs from outdoor-housed layers were examined for egg weight, albumen, yolk and shell content, albumen height and pH, and albumen and yolk dry matter content. 3. Interactions between layer age and housing systems were found for egg weight, eggshell content, albumen height, albumen pH, and dry matter content of the albumen and yolk. This was mainly due to the greater variation with age in the outdoor layers, compared to the caged layers. 4. Irrespective of age eggs from outdoor layers were relatively broader than eggs from the caged layers. Yolk colour was considerably darker in the outdoor group (11.0 vs 9.3). 5. We concluded that it is more difficult to maintain constant external and internal egg quality in an outdoor housing system than in a battery cage system. Factors that determine the greater fluctuations in internal egg quality need to be investigated.

Effect of husbandry system on broken bones and bone strength in hens

The effects of rearing system, forced moulting and three different layer housing systems on broken bones and bone strength, were examined in hens at the end of lay. Weak bones and broken bones were more common in battery hens which had been reared to point of lay on deep litter rather than in cages. The incidence of old breaks was greater in perchery birds (14 per cent) than in tiered terrace birds (5 per cent), and there was also a difference between their incidence in two types of perchery design (17 per cent and 11 per cent). Moulting was associated with a transient decline in bone strength, followed by an increase in strength during the second lay.