Free-range Housing Systems Research Articles

Indoor side fidelity and outdoor ranging in commercial free-range chickens in single- or double-sided sheds

The ranging behaviour of broiler chickens kept in free-range housing systems remains poorly understood, despite access to the outdoor range being their main feature. We investigated the impact of allowing chickens to have range access on both sides vs. one side of the shed, using 24 flocks of approximately 40,000 Ross 308 chickens of mixed sex on one commercial farm across winter and summer. Sheds were identical and pseudo-randomly allocated to either double-sided (no modification) or single-sided (by keeping one side closed at all time) range access treatment. Flocks were first provided with range access from 15 to 17 and 21 to 27days of age for summer and winter flocks, respectively. Live outdoor observations were conducted daily for the first week after first range access and every other day from the second week onwards until the day prior to depopulation (44days of age), twice daily in each morning and evening during anticipated peaks of range use. Indoor side fidelity was also assessed by spray marking 320 chickens in total on the right- and left-hand side of the shed, one colour each side, and conducting two to four repeated counts of the colour-marked individuals in each location over the week following marking. Indoor count results showed that colour-marked chickens had 50% chance of being found on either side of the shed (P<0.001 from a side preference), and therefore did not support the hypothesis that chickens show indoor side fidelity in commercial conditions. Consequently, we could not elucidate whether an individual chicken would cross to the opposite side of the shed to access the range. Winter flocks had infrequent range access and low number of birds on the range (49±175 chickens outdoor at any one time). For summer flocks, the ANOVA model explained 72.5% of the variance, with the number of chickens observed on the range being affected by the interaction of treatment and age (P<0.001); more chickens were observed on the range when range access was available on both sides of the shed compared to a single side, from the seventh day of range access onwards. Hence, shed design can limit ranging in broiler chickens during the period of high ranging activity. For double-sided sheds, the number of chickens on the range steadily increased until an average of 28% of the flock could be seen on the range at one time, by 44days of age prior to depopulation.

Egg Production and Quality Traits of Layers kept in Free Range Housing System

Egg Production and Quality Traits of Layers kept in Free Range Housing System

Wild and Domestic Pig Interactions at the Wildlife-Livestock Interface of Murchison Falls National Park, Uganda, and the Potential Association with African Swine Fever Outbreaks.

Bushpigs (BPs) (Potamochoerus larvatus) and warthogs (WHs) (Phacochoerus africanus), which are widely distributed in Eastern Africa, are likely to cohabitate in the same environment with domestic pigs (DPs), facilitating the transmission of shared pathogens. However, potential interactions between BP, WH, and DP, and the resulting potential circulation of infectious diseases have rarely been investigated in Africa to date. In order to understand the dynamics of such interactions and the potential influence of human behavior and husbandry practices on them, individual interviews (n = 233) and participatory rural appraisals (n = 11) were carried out among Ugandan pig farmers at the edge of Murchison Falls National Park, northern Uganda. In addition, as an example of possible implications of wild and DP interactions, non-linear multivariate analysis (multiple correspondence analyses) was used to investigate the potential association between the aforementioned factors (interactions and human behavior and practices) and farmer reported African swine fever (ASF) outbreaks. No direct interactions between wild pigs (WPs) and DP were reported in our study area. However, indirect interactions were described by 83 (35.6%) of the participants and were identified to be more common at water sources during the dry season. Equally, eight (3.4%) farmers declared exposing their DP to raw hunting leftovers of WPs. The exploratory analysis performed suggested possible associations between the farmer reported ASF outbreaks and indirect interactions, free-range housing systems, dry season, and having a WH burrow less than 3 km from the household. Our study was useful to gather local knowledge and to identify knowledge gaps about potential interactions between wild and DP in this area. This information could be useful to facilitate the design of future observational studies to better understand the potential transmission of pathogens between wild and DPs.

Confined housing system increased abdominal and subcutaneous fat deposition and gene expressions of carbohydrate response element-binding protein and sterol regulatory element-binding protein 1 in chicken.

Free-range production system is increasingly being used in poultry breeding and feed production in many countries. The objective of the current experiment was to evaluate the effects of different raising systems on fat-related traits and mRNA levels of liver lipogenesis genes in Erlang Mountainous chicken. Each of 10 birds (91 day old) from caged, indoor-floor housed, and free-range housing systems was slaughtered, and fat-related traits, live body weight (BW), subcutaneous fat thickness (SFT), abdominal fat weight (AFW), abdominal fat percentage (AFP), and intramuscular fat content were determined. The mRNA levels of liver X receptor α, carbohydrate response element-binding protein (ChREBP), sterol regulatory element-binding protein-1 (SREBP1), and fatty acid synthase were detected. The caged chicken exhibited significantly higher BW, SFT, and AFW than those of free-ranged chicken (P < 0.05). All the 4 genes had a similar expression pattern, and they showed the highest level in caged chicken, while the lowest level was found in free-ranged chicken. Association analysis indicated that there were significant (P < 0.05) or highly significant (P < 0.01) positive correlations between the mRNA levels of ChREBP, SREBP1, and fat traits of SFT, AFW, and AFP. Thus, we deduced that increased fat deposition in caged chicken was probably induced by increased gene expression of ChREBP and SREBP1 in the liver.

Microbiological contamination of shell eggs produced in conventional and free-range housing systems

The present study was conducted to determine microbiological contamination of free-range and conventional chicken eggs produced under controlled conditions. Eighty-four certified Salmonella-free Bovan Brown chicks (age 2 days) were grown in 6 separate floor pens until age 16 weeks, and then moved into 3 conventional battery cages (BC) or 3 free-range (FR) housing systems. Total aerobic microorganisms and Enterobacteriaceae on egg shell surfaces were enumerated weekly when the hens were 20–27 weeks of age (N = 535 and N = 541 for BC and FR, respectively). Prevalence of Salmonella and Campylobacter were determined on crushed egg shells (N = 212 and N = 176, respectively) and in feces (N = 36 and N = 30, respectively) collected from hens at 24 and 28 weeks of age. Counts of total aerobic microorganisms recovered from BC and FR eggs ranged from 5.0 to 6.0 log10 CFU/mL. Numbers of Enterobacteriaceae averaged 1.0 log CFU/mL higher (90% greater) on FR eggs than on eggs from BC hens. Salmonella was not detected on any of the eggs collected from BC hens (0/212), but prevalence on eggs collected from FR hens was 2.36% positive (5/212). Prevalence of Campylobacter recovered from eggs collected from FR (26.1% positive or 46 out of 176 positive) was significantly higher (P ≤ 0.0001) than the prevalence of Campylobacter recovered from eggs from BC hens (7.4% positive or 13 out of 176 positive). These data demonstrate that FR eggs, where hens have more contact with eggs after oviposition, have greater microbiological contamination on the egg shell surface than eggs produced in the BC cage systems.

Isolation of dermatophytes and related species from domestic fowl (Gallus gallus domesticus).

We investigated 793 bird combs [645 chickens and 148 fighting cocks (Shamo)] to determine the prevalence of dermatophytes and their related fungal species. The targeted fungal species were recovered from 195 of the 793 examined birds (24.6 %). Prevalence ratios were compared in temperate (the mainland) and subtropical (Nansei Islands) areas, genders, strains, breeding scale (individual and farm), and housing system (in cage and free ranging). The frequency of the fungal species in the mainland, males, fighting cocks, breeding scale by individual nursing, and free-range housing system exhibited significantly higher positive ratios than that in the other groups. A total of 224 dermatophytes and related species were isolated, including 101 Arthroderma (Ar.) multifidum, 83 Aphanoascus (Ap.) terreus, five Uncinocarpus queenslandicus, two U. reesii, two Ap. pinarensis, one Amauroascus kuehnii, one Ar. simii, one Gymnoascus petalosporus, one Microsporum gallinae, and 28 Chrysosporium-like (Chrysosporium spp.) isolates, which were identified using internal transcribed spacer regions of ribosomal RNA gene sequences. The predominant fungal species in the mainland was Ap. terreus and that in the Nansei Islands was Ar. multifidum. Pathogenic fungal species to humans and animals were limited to M. gallinae and Ar. simii, which corresponded to 0.025 % of the isolates in this study.

The influence of a free-range housing system on pig growth, carcass composition and meat quality

The objective of this investigation was to compare the productivity results, carcass composition and meat quality of pigs reared indoors (average ambient temperature 19.4°C) or outdoors (average ambient temperature 16.0°C) during the summer–autumn periods. A total of 56 Lithuanian White (LW)×Swedish Yorkshire (SY)×English Large White (ELW) crossbred pigs were selected out of 14 litters and allotted into two analogous by origin, gender, weight and condition score groups of 26 animals each. The indoor group pigs were raised in pens of 18.5 m2 area. The outdoor group pigs were raised outdoors in enclosures of 850 m2 area. The productivity of pigs was determined by individual weighing. The carcass measurements (carcass weight and length, dressing percentage, backfat thickness and loin lean area) were determined and recalculated for 100 kg weight. The samples of the longissimus muscle were analysed for physicochemical indicators of meat. The study indicated that in the growing period and during the whole experiment, the outdoor group pigs gained higher average daily weight, respectively, by 26.8 (P=0.003) and 12.7% (P=0.013) than the pigs in the indoor group. The carcass traits were not different between the groups, but in all cases the outdoor group showed lower fat thickness. Rearing environment did not significantly influence the physicochemical indicators of meat and backfat, but the meat from the pigs raised outdoors had slightly higher (0.76%, P=0.088) crude protein levels.

Pop hole use by hens with different keel fracture status monitored throughout the laying period

The aim of this work was to study the effect of keel fractures on the extent to which free-range hens access the range through pop holes. Over two consecutive laying...

Comparative analysis of lipophilic compounds in eggs of organically raised ISA Brown and Araucana hens

AbstractHens’ eggs represent a rich source of important nutrients, including lipids and carotenoids. The lipid composition of hens’ eggs is influenced by genetic factors, age, and diet. The aim of this study was to compare the fatty acids, cholesterol, and carotenoids content of the egg yolk of ISA Brown and Araucana hens grown in free-range housing systems. Fatty acids and cholesterol were analysed by GC-FID and GC-MS and carotenoids were quantified by RP-HPLC-PDA.The Araucana egg yolk has a higher lipid content and higher egg-to-albumen ratio than the ISA Brown yolk, while the total cholesterol, carotenoids content and profile are not significantly different. The lipids of the Araucana egg yolk have a higher content of mono-unsaturated fatty acids (MUFAs), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) and a better n-6/n-3 ratio than the ISA Brown egg yolk lipids. The major carotenoids were lutein and zeaxanthin, which account for more than 83 % in egg yolk. Eggs of both breeds, when raised organically, represent very good sources of highly bio-available lutein and zeaxanthin, pigments which are related to lower risk of age-related macular degeneration. We report for the first time on the fatty acids composition in lipid fractions and the profile and content of carotenoids of the Araucana egg yolk.

Growth, slaughter and gastrointestinal tract traits of three turkey genotypes under barn and free-range housing systems

1. This study was conducted to assess the impact of genotype and outdoor access (and gender when appropriate) on growth rate and carcass yield. 2. One slow-growing genotype (Bronze; B, n = 129), a commercial fast-growing genotype (Hybrid; H, n = 186) and a medium-growing genotype (crosses; H × B, n = 78) were housed (straight-run) for 21 weeks of age. Each genotype was assigned to 3 pens of 20–23 birds each and raised in indoor floor pens in a curtain-sided house with ventilation fans; the B, H and H × B genotypes were also assigned to 3, 4 and 2 floor pens (2 m2 approximately) with outdoor access (during daylight hours), respectively. All animals were fed ad libitum a commercial diet and birds were commercially processed. After reaching the commercial live weight at 17 and 21 weeks of age, 4 birds (two females and two males) per replicate were slaughtered to determine the yields of carcass, breast, and thigh, abdominal fat and edible inner organs. Gastrointestinal tract characteristics such as length and weight of whole gut were analysed. 3. No significant interaction between genotype and housing systems was observed. Significant differences were found for all traits among genotypes. The live weight was higher in H and H × B genotypes from 7 to 15 weeks and from 7 to 21 weeks of age compared to B genotype, respectively. The live weight of H genotype was higher than that of H × B genotype from 15 to 21 weeks of age. The carcass weight and yield, and the relative weights of the edible inner organs and whole gut, and the relative length of whole gut were significantly affected by genotype and sex of birds. Differences in growth performance, relative weight of breast meat, wings or thighs between birds raised on barn or free-range were negligible. In conclusion, while the development in growth performances was related to strain, the traits at slaughter were related to both strain and sex, and were unaffected by housing system.

Effects of Housing Systems on Growth Performance, Blood Plasma Constituents and Meat Fatty Acids in Broiler Chickens

A research was conducted to determine the influence of the conventional and the free-range broiler housing systems using female broiler chicks had low hatching weight on growth performance, breast meat characteristics and some blood plasma parameters. In the conventional (totally confined) housing system sixty one-day-old female Ross broiler chicks were placed in indoor floor pens with three replicates of 20 chicks. In the free-range (partly-confined) housing system, sixty one-day-old Ross broiler chicks were placed in indoor floor pens and also accessed to a grass paddock during 44 day experimental period after 7 days old. Birds of both systems were fed the same commercial broiler diet. The free-range housing system significantly decreased the total feed intake and body weight of broilers (p<0.05). The redness (a* color) and yellowness (b* color) in breast meat were affected by the housing systems (p<0.05). The housing systems had no affect on fatty acids composition of breast meat (p>0.05). The plasma triglyceride and VLDL levels of the conventional reared birds were significantly higher than those reared the free-range (p<0.05). In conclusion, longer growth period was necessary to the free-range reared broilers.

The influence of severe prolonged exercise restriction on the mechanical and structural properties of bone in an avian model

Many studies have described the effects of exercise restriction on the mammalian skeleton. In particular, human and animal models have shown that reduction in weight bearing leads to generalised bone loss and deterioration of its mechanical properties. The aim of this study was to assess the effect of prolonged exercise restriction coupled with heavy calcium demands on the micro-structural, compositional and mechanical properties of the avian skeleton. The tibiae and humeri of 2-year-old laying hens housed in conventional caging (CC) and free-range (FR) housing systems were compared by mechanical testing and micro-computed tomography (microCT) scanning. Analyses of cortical, cancellous and medullary bone were performed. Mechanical testing revealed that the tibiae and humeri of birds from the FR group had superior mechanical properties relative to those of the CC group, and microCT scanning indicated larger cortical and lower medullary regions in FR group bones. Cancellous bone analysis revealed higher trabecular thickness and a higher bone volume fraction in the FR group, but no difference in mineral density. The biomechanical superiority of bones from the FR group was primarily due to structural rather than compositional differences, and this was reflected in both the cortical and cancellous components of the bones. The study demonstrated that prolonged exercise restriction in laying hens resulted in major structural and mechanical effects on the bird skeleton.

Auslaufverhalten von Legehennen - Automatisierte Erfassung und Auswertung über Bildanalyse

Due to legal changes, as well as the increasing importance of organic agriculture, free-range housing systems for laying hens are on the rise. There are only a few reliable investigations about free-range behaviour and to what extent the laying hens take advantage of the free-range. At the Bavarian State Institute of Agriculture the free-range behaviour is being researched with the help of automatic image recording and analysis. On selected days during the study, the average number of hens on the free-range was 109 out of about 500. The identification accuracy on these days was about 84%.

The growth and carcass and meat characteristics of pigs raised in a free-range or conventional housing system

The growth performance and the carcass and physical and chemical characteristics of the meat of 24 Landrace X Large White pigs were compared when reared under a free-range or a conventional housing system. The free-range pigs had lower feed intakes and slower growth rates than the conventionally housed pigs. The free-range pigs also had a lower P2 fat depth and therefore yielded a carcass with a higher percentage lean meat. Housing systems had no effect on the weight distribution of the commercial cuts (as a percentage of cold carcass weight). The meat from the free-range pigs was slightly more reddish in colour, but apart from that housing systems had no effect on the water-holding capacity (WHC) of the meat, its initial pH (pH45) or its final pH (pH24). The meat from the free-range pigs had the same shear force (WBS) values as those of the conventionally housed pigs. Housing systems had an influence on the fatty acid composition. Stearic acid (C18:0) was significantly lower in the meat of the free-range pigs than that of the conventionally housed pigs while linoleic acid (C18:2n-6) and polyunsaturated fatty acid (PUFA) concentrations were significantly higher. However, the moisture, fat, protein and ash contents as well as the mineral composition in the meat were unaffected by housing systems. It could be concluded that pigs raised in a conventional housing system produced meat with similar quality characteristics to that of pigs raised in a free-range housing system.

Identification of quantitative trait loci for receiving pecks in young and adult laying hens

Feather pecking (FP) is a major problem in cage and free-range housing systems. In free-range systems, FP is more difficult to control. It is not known why a victim is being pecked. It could be that a bird is genetically predisposed to be pecked. To study the genetics of FP behavior, a large F2 population of 630 hens was generated from a cross between two commercial laying lines differing in their propensity to feather peck. The traits measured at 6 and 30 wk of age were receiving gentle FP, receiving severe FP, and receiving aggressive pecking. In addition, receiving toe pecking (TP) was also measured at 30 wk of age. For receiving gentle FP at 6 wk of age, a significant QTL on GGA1 and three different suggestive QTL were identified on GGA2, GGA6, and GGA7, respectively. For receiving gentle FP at 30 wk of age, a suggestive QTL on GGA5 was detected. For receiving aggressive pecking, a suggestive QTL was detected on GGA3. For receiving TP, three suggestive QTL were detected on GGA1, GGA5, and GGA23, respectively. The different QTL detected for receiving gentle FP at different ages indicate that this trait is regulated by different genes in young and adult hens.

Physiological Responses of Laying Hens to the Alternative Housing Systems

Measurements of differential leucocyte count, H/L (Heterophil to Lymphocyte) ratio and Ab (Antibody) titres to commercial used vaccines, ND (Newcastle Disease) and IB (Infectious Bronchitis) were employed to investigate whether the exposure of laying hens to different housing systems was associated with haematological-immunological changes. Layers were kept in three different housing systems: conventional battery cages, modified cages and an intensive free-range housing system. Differential leucocyte count and H/L ratio were used as indicators of stress response and sensitive biomarkers crucial to immune function, whereas the Ab levels to IB and ND vaccines were measured to assess humoral- mediated immunity. This study indicated that in hens exposed to the three various housing conditions H/L ratio was found to be significantly different, 0.58, 0.43 and 0.38, respectively. The results show that in hens kept in battery cages heterophils were raised, while lymphocytes decreased. Although, differences in H/L ratio suggest that hens of different housing systems should have a reduced antibody response and several investigators have recommended that environmental stressors decrease Ab production this was not demonstrated in this survey. Ab titre presented as log was unaffected by any housing system. A sligh t 10 negative correlation between H/L ratios and antibody levels was also observed. The results would suggest that housing conditions and social stress might have a great effect on the stress response (H/L ratio) while humoral response seems unaltered.