Owner demographic factors are associated with suitable pet rabbit housing provision in the United Kingdom.

BACKGROUND: Rabbits are popular pets, but research into their welfare is limited. This study analysed the potential association(s) between the provision of suitable housing and owner demographic factors. METHODS: Data from 2017, 2018 and 2019 PDSA Animal Wellbeing (PAW) report surveys gave a sample of 1333 UK rabbit owners. Whether the rabbit housing was adequate or inadequate was ascertained by asking owners to indicate images of hutch and run size or indoor environment type that were similar to their own. The owner demographic factors collected included gender, education, household income and deprivation. Chi-squared tests and binary logistic regression (univariable and multivariable) were used to investigate factors associated with adequate/inadequate housing. RESULTS: One-third (31.2%) of rabbits lived in inadequate housing and half were housed alone (51.4%). Male owners were more likely to report providing inadequate housing than females (odds ratio [OR] = 1.795, 95% confidence interval [CI] 1.319-2.441, p < 0.001). Compared to owners over 55 years old, those aged 25-34 years were more likely to house their rabbits inadequately (OR = 2.050, 95% CI 1.286-3.267, p = 0.003). Owners with a household income below average were more likely to report providing inadequate housing compared to those with a household income above average (OR = 1.406, 95% CI 1.025-1.928, p = 0.035). CONCLUSION: The findings identify that inadequate rabbit housing is provided by owners of all ages, genders and deprivation levels but highlight some particular owner demographics that could be useful to target if resources are limited.

Rats as pets: Predictors of adoption and surrender of pet rats (Rattus norvegicus domestica) in British Columbia, Canada.

Whereas much research has been conducted on rats in their roles as pests and laboratory animal models, little is known about rats in their role as companion animals. However, rats have become the third most common companion animal admitted to the British Columbia Society for the Prevention of Cruelty to Animals (BC SPCA) shelter system after cats and dogs. This paper analyses 5 years of province-wide rat admission and outcome data (n = 3,392) at the BC SPCA. Most rats that entered BC SPCA shelters were white, sexually intact, and pups less than 6 months old. Rats were mostly relinquished by their owners, and the most common surrender reasons were due to owner-related issues and housing issues. Reasons for euthanasia were primarily poor health and neonatal age. A multiple linear regression model found that rats that were either senior, albino, unhealthy, seized by humane officers, or born onsite tended to stay longer in shelters (F[12, 1466] = 9.565, p < .001, adjusted R2 = .06). Time to adoption for albino rats was 79% longer than for white rats. These findings help us understand the preferences of rat adopters and why the rat-human relationship may fail. Results may also be useful to improve the quality of life for pet rats by identifying programs to reduce their length of stay in animal shelters. Finally, our study highlights new questions for welfare research in an understudied companion animal-the pet rat.

An assessment of thermoneutral housing conditions on murine cardiometabolic function.

Mouse models are used to model human diseases and perform pharmacological efficacy testing to advance therapies to humans; most of these studies are conducted in room temperature conditions. At room temperature (22°C), mice are cold-stressed and must use brown adipose tissue (BAT) to maintain body temperature. This cold stress increases catecholamine tone to maintain adipocyte lipid release via lipolysis, which will fuel adaptive thermogenesis. Maintaining rodents at thermoneutral temperatures (28°C) ameliorates the need for adaptive thermogenesis, thus reducing catecholamine tone and BAT activity. Cardiovascular tone is also determined by catecholamine levels in rodents, as ß-adrenergic stimuli are primary drivers of not only lipolytic but also ionotropic and chronotropic responses. As mice have increased catecholamine tone at room temperature, we investigated how thermoneutral housing conditions would impact cardiometabolic function. Here, we show a rapid and reversible effect of thermoneutrality on both heart rate and blood pressure in chow-fed animals, which was blunted in animals fed a high-fat diet. Animals subjected to transverse aortic constriction displayed compensated hypertrophy at room temperature, whereas animals displayed less hypertrophy and a trend toward worse systolic function at thermoneutrality. Despite these dramatic changes in blood pressure and heart rate at thermoneutral housing conditions, enalapril effectively improved cardiac hypertrophy and gene expression alterations. There were surprisingly few differences in cardiac parameters in high-fat-fed animals at thermoneutrality. Overall, these data suggest that thermoneutral housing may alter some aspects of cardiac remodeling in preclinical mouse models of heart failure.NEW & NOTEWORTHY Thermoneutral housing conditions cause rapid and reversible changes in mouse heart rate and blood pressure. Despite dramatic reductions in heart rate and blood pressure, thermoneutrality reduced the compensatory hypertrophic response in a pressure overload heart failure model compared with room temperature housing, and ACE inhibitors were still efficacious to prevent pressure overload-induced cardiac remodeling. The effects of thermoneutrality on heart rate and blood pressure are abrogated in the context of diet-induced obesity.

Effects of pen enrichment on leg health of fast and slower-growing broiler chickens.

Pen enrichment for broiler chickens is one of the potential strategies to stimulate locomotion and consequently contribute to better leg health and welfare. This study was designed to evaluate effects of using a plethora of pen enrichments (barrier perches, angular ramps, horizontal platforms, large distance between feed and water and providing live Black Soldier fly larvae in a dustbathing area) on tibia characteristics, locomotion, leg health and home pen behaviour of fast and slower-growing broiler chickens. The experiment was set up as a 2 x 2 factorial arrangement with a total of 840 male broiler chickens in a complete randomized design (7 pens per treatment and 30 chickens per pen) with the following treatments: 1) pen enrichment (enriched pen or non-enriched pen); 2) broiler strain (fast-growing Ross 308 or slower-growing Hubbard JA 757). Home pen behaviour and use of enrichment were observed. At approximately 1400 and 2200 g body weight, two chickens per pen were randomly selected and slaughtered, to investigate tibia morphological, biophysical and mechanical characteristics and leg health. Pen enrichment positively affected tibia biophysical characteristics, e.g., osseous volume (Δ = 1.8 cm3, P = 0.003), total volume (Δ = 1.4 cm3, P = 0.03) and volume fraction (Δ = 0.02%, P = 0.002), in both fast and slower-growing chickens, suggesting that pen enrichment particularly affects ossification and mineralization mechanisms. Accordingly, locomotion and active behaviours were positively influenced by pen enrichment. However, pen enrichment resulted in lower body weight gain in both strains, which might be due to higher activity or lower feed intake as a result of difficulties of crossing the barrier perches. Regarding the strain, slower-growing chickens showed consistently more advanced tibia characteristics and more active behaviour than fast-growing chickens. It can be concluded that pen enrichment may lead to more activity and better bone development in both fast and slower-growing chickens.

Animal welfare and zoonosis risk: anti-Trichinella antibodies in breeding pigs farmed under controlled housing conditions.

BACKGROUND: Domesticated pigs are the main source of Trichinella sp. infections for humans, particularly when reared in backyards or free-ranging. In temperate areas of southern Europe, most pigs are farmed under controlled housing conditions, but sows and sometimes fattening pigs have access to outdoors to improve animal welfare. The aim of the present study was to investigate whether outdoor access of breeding pigs farmed under controlled housing conditions can represent a risk for Trichinella sp. transmission when the farm is located in an agricultural area interspersed with wooded areas and badlands, where Trichinella spp. could be present in wildlife. METHODS: Serum samples were collected from 63 breeding sows and one boar before and after their access to an open fenced area for 2 months and from 84 pigs that never had outdoor access. Samples were screened for anti-Trichinella antibodies by ELISA, and positive sera were confirmed using Western blot (Wb) excretory/secretory antigens. To detect Trichinella sp. larvae, muscle tissues from serologically positive and negative pigs were tested by artificial digestion. RESULTS: Thirteen (20.6%) sows and one boar tested positive with both ELISA and Wb. No larvae were detected in muscle samples of serologically positive and serologically negative pigs. Positive serum samples were then tested by Wb using crude worm extract as antigens. The Wb banding pattern displayed was that characteristic of encapsulated species (Trichinella spiralis or Trichinella britovi). CONCLUSIONS: The detection of anti-Trichinella antibodies without larvae in the pig muscles, supported by epidemiological data, suggests that pigs may have been exposed to T. britovi. This study stresses the importance of instigating monitoring systems at farm level to prevent Trichinella sp. transmission and to investigate, through a landscape parasitological study, the suitability of a site before the planting of a high containment level pig farm in which the sows can have outside access to improve their welfare during pregnancy.

[The lying and rumination behavior of healthy dairy cows housed in tie stalls is associated with bedding depth]. / Das Liege- und Wiederkauverhalten klinisch gesunder Milchkühe in Anbindehaltung ist assoziiert mit der Einstreutiefe.

INTRODUCTION: The lying and rumination behavior of dairy cows is internationally used as an animal welfare indicator. Dairy cow housing in Switzerland is subordinated to detailed legal requirements. It is particularly described that the lying area for cows must be covered with a sufficient amount of bedding. In the current study, we investigated whether bedding depth influences the lying and rumination behavior and thus, the animal welfare of healthy dairy cows housed in tie stalls. Bedding depth was categorized as ≤ 2 cm and > 2 cm. The lying and rumination behavior of 145 cows from 33 farms was recorded and analyzed considering farm effects; 105 cows were housed on ≤ 2 cm bedding, and 40 cows on > 2 cm bedding. Cows on > 2 cm bedding had on average a one hour longer daily lying time compared with cows on ≤ 2 cm bedding (mixed-effects linear regression: mean difference [cows on > 2 cm bedding - cows on ≤ 2 cm bedding] = 60,7 min/d; standard error = 28,6 min/d; p-value = 0,037). The odds of a cow to lie while ruminating were significantly higher in cows on > 2 cm bedding against cows on ≤ 2 cm bedding (mixed-effects logistic regression: Odds ratio = 1,27; CI95% [1,17-1,38]; p-value 2 cm can make a significant difference in the lying and rumination behavior of healthy dairy cows housed in tie stalls. Consequently, the animal welfare of dairy cows in tie stalls is improved by providing at least 2 cm of bedding.

INTRODUCTION: Le comportement de couchage et de rumination des vaches laitières est internationalement utilisé comme indicateur du bien-être animal. En Suisse, la détention des vaches laitières est soumise à des règles légales précises. Il est entre autre prescrit que l'aire de couchage doit être pourvue d'une litière appropriée en quantité suffisante. Dans la présente étude nous avons examiné si l'épaisseur de la litière avait une influence sur le comportement de couchage et de rumination, et ainsi aussi sur le bien-être animal, de vaches laitières saines détenues en stabulation entravée. L'épaisseur de la litière a été répartie en catégories de ≤ 2 cm respectivement de > 2 cm. Le comportement de couchage et de rumination de 145 vaches en provenance de 33 exploitations a été documenté et analysé en tenant compte de l'impact de l'exploitation: 105 vaches ont été détenues sur ≤ 2 cm de litière et 40 vaches sur > 2 cm de litière. Les vaches détenues sur > 2 cm de litière avaient en moyenne une durée de couchage journalière prolongée d'une heure (régression linéaire mixte: différence moyenne [vaches sur > 2 cm de litière ­ vaches sur ≤ 2 cm de litière] = 60,7 min/d; écart type = 28,6 min/d; Valeur p = 0,037). La probabilité que les vaches soient couchées lors de la rumination était significativement plus grande chez les vaches détenues sur > 2 cm de litière par rapport aux vaches détenues sur ≤ 2 cm de litière (régression logistique mixte: odds ratio = 1,27; CI95% [1,17­1,38]; Valeur p 2 cm est associée à des différences significatives de comportement de couchage et de rumination de vaches saines détenues en stabulation entravée. En conséquence, la mise à disposition d'un minimum de 2 cm de litière sur les zones de couchage des vaches détenues en stabulation entravée permet une amélioration quantifiable du bien-être animal.

Behavioural effects of cage systems on the G93A Superoxide Dismutase 1 transgenic mouse model for amyotrophic lateral sclerosis.

Environmental factors inherent to animal facilities can impact on the neuro-behavioural phenotype of laboratory mice and genetic mouse models for human diseases. Many facilities have upgraded from traditional 'open filter top' cages (FT) to individually ventilated cage (IVC) systems, which have been shown to modify various behavioural responses of laboratory mice. Importantly, the impact of IVC housing on the G93A superoxide dismutase 1 mouse model of amyotrophic lateral sclerosis (ALS) is currently unknown. Male and female wild type-like (WT) and heterozygous SOD1G93A mice were group-housed in FT or IVC systems from PND 30 ± 5 onwards. Body weight and motor function were assessed weekly from 15 weeks onward. Mice were also tested for cognitive abilities (i.e., fear conditioning and social recognition memory) and sensorimotor gating (i.e., prepulse inhibition: PPI). SOD1G93A mice lost body weight, and their motor function degenerated over time compared with control littermates. Motor impairments developed faster when SOD1G93A females were housed in IVCs. Context and cue freezing were increased in SOD1G93A females compared with controls, whereas all SOD1G93A mice exhibited lower acoustic startle and PPI than WT mice. IVC housing led to an increase in cue freezing in males and reduced the severity of PPI deficits in SOD1G93A females. Overall, IVC housing impacted moderately on the SOD1G93A phenotype but central behavioural deficits were still evident across housing conditions. Nonetheless, our findings indicate the importance of assessing the effect of cage system in genetic mouse models as these systems can modulate the magnitude and onset of genotypic differences.

Identification of blood immune and metabolic indicators explaining the variability of growth of pigs under contrasted sanitary conditions.

BACKGROUND: Health and growth of pigs are affected by the hygiene of housing. Lower growth performance observed in poor hygiene of housing conditions is explained by reduced feed intake and metabolic changes caused by the activation of body defences. In a previous experiment, we reported contrasted average values of body weight gain, concentrations of circulating metabolites, redox and immune indicators in blood of pigs housed in good or poor hygiene conditions during the growing period. This study addressed inter-individual variability in these responses to determine whether a particular blood profile explains average daily gain (ADG) of the pig. RESULTS: The data originated from 160 growing pigs, half of which subjected to a hygiene challenge for 6 weeks (W0 to W6) and the others housed in good hygiene conditions. Pigs originated from two lines divergently selected for residual feed intake (RFI). Individual body weights were recorded during this period, and relative ADG (rADGW0-W6) was calculated as the ADG corrected by the initial body weight measured at W0. Blood samples were taken before (W0) and 3 weeks (W3) after the beginning of the challenge. The analysed dataset consisted of 51 metabolites and indicators of immune and inflammatory responses measured on 136 pigs having no missing value for any variables, when calculated as the differences W3 minus W0 in circulating concentrations. An algorithm tested all possible linear regression models and then selected the best ones to explain rADGW0-W6. Six variables were identified across the best models and correlated with rADGW0-W6 with a goodness of fit (adjusted R2) of about 67%. They were changes in haptoglobin, global antioxidant capacity of plasma (Biological Antioxidant Power or BAP), free fatty acids, and 3 amino acids: leucine, tryptophan, and 1-methylhistidine. The effects of housing conditions and RFI lines were comprised in the variables of the selected models and none of these conditions improved accuracy of the predictive models, leading to genericity of the pinpointed metabolic changes in relation to variability of ADG. CONCLUSIONS: This approach allows us to identify blood variables, whose changes in blood concentrations correlated to ADG under contrasted sanitary conditions.

Associations between animal-based measures at 11 wk and slaughter data at 20 wk in turkey toms (Meleagris gallopavo).

To monitor animal welfare on a commercial scale, systematic collection and evaluation of slaughterhouse data is the most feasible method. However, we need to know whether slaughterhouse data retrospectively and reliably reflect information about the birds' welfare on-farm. The aim of this study was therefore to investigate associations between animal-based welfare measures in flocks of turkey toms at 11 wk of age recorded with the transect walk and slaughter data at 20 wk of age. A total of 20 commercial flocks of turkey toms were visited, where an observer walked the transects in a random order and recorded the total number of birds per transect that were immobile, lame, with visible head, tail, or wing wounds, small, featherless, dirty, sick, terminal, or dead. Slaughterhouse data were provided for each flock. Univariate and multivariate linear regression models were used to investigate the associations between on-farm and slaughterhouse measures. Increased prevalence of immobile toms at week 11 resulted in more birds rejected at slaughter owing to leg issues (P = 0.02) and airsacculitis (P < 0.001). More lame birds on-farm were associated with an overall higher rejection rate at slaughter (P < 0.001). Flocks with more featherless birds had significantly more birds being rejected at slaughter owing to skin issues (P = 0.02). More dirty birds at week 11 resulted in more birds being rejected owing to airsacculitis at slaughter (P < 0.001). A higher mortality on-farm was associated with more birds rejected for being too small (P = 0.04). In conclusion, significant associations between animal-based measures of turkey toms as assessed by the transect walk method on-farm at 11 wk and slaughter data at 20 wk were identified.

Litter and perch type matter already from the start: exploring preferences and perch balance in laying hen chicks.

Early chick environment, such as provision of litter and perches, can be a predictor of laying hen welfare. Inadequate or nonpreferred litter and perch types could have similar negative effects as those seen when not providing these resources at an early stage, such as increased feather pecking and cannibalism in adult flocks. However, suitable litter and perch types for chicks are not well explored. In the present project, 6 different types of litter (crushed straw pellets, hemp shavings, peat, sand, straw, wood shavings) and 6 different types of perches (narrow or wide forms of rope, flat or round wood) were presented in a controlled way (3 at a time) to chicks in 6 pens. Usage was compared in 93 chicks of Lohmann Selected Leghorn Classic divided across the pens, during their first 3 wk after hatch. Different litter types were seen to be preferred for different behaviors. The majority of dustbathing bouts occurred in sand and peat. Chicks foraged more in wood shavings, hemp shavings, and sand than in peat and pellets (P < 0.05). Perch width and shape were found to affect both usage and perch balance, measured as the probability of successful or problematic landings. The wide rope was generally used more during the first week (P < 0.05) and was used more for sleeping or resting (P < 0.05) than the other wide perch types. Furthermore, birds were more likely to land on the wide rope or on flat perches successfully than they were to have a problematic landing (P < 0.05). That birds were more likely to be observed preening on flat perches than on the potentially shaky rope perches could further reflect a sense of security. Our results suggest that presenting several litter types could better fulfill chicks' behavioral needs and that flat perches or a wide rope (4.5-cm diameter) could be appropriate perch types for laying hen chicks and thereby promote early perch use and training.

Effects of dietary energy levels on performance and carcass yield of 2 meat-type broiler lines housed in hot and cool ambient temperatures.

Two meat-type broiler lines, line A and line B were fed experimental diets from 22-42 d with objectives to determine the effects of dietary metabolizable energy (ME) levels on feed intake (FI), performance, body composition, and processing yield as affected by environmental grow-out temperatures. Two thousand fifty male chicks from line A and 2,050 male chicks from line B were reared in 90-floor pens, 45 chicks per pen utilizing primary breeder nutrition and husbandry guidelines for starter (1-10 d) and grower (11-21 d) phases. Experimental finisher diets consisted of 5 increasing levels of apparent nitrogen corrected ME (2,800, 2,925, 3,050, 3,175, and 3,300 kcal/kg set at 19.5% crude protein and 1.0% dLys at each level) to represent 80, 90, 100, 110, and 120% ME of Evonik AminoChick energy level giving 2 × 5 factorial design and were fed from 22-42 d. All other amino acid levels in diets were formulated to a fixed ratio of dLys level. There were nine replicate pens for each diet and each line. The experiment was conducted twice-once in hot season (barn averages: 77.55 ˚F and 86.04% RH) and another in cool season (barn averages: 69.91 ˚F and 63.98% RH) of the year. Results showed that FI and feed conversion ratios (FCR) decreased (P < 0.05) linearly (R2 = 0.9) by 61.25 g and 0.073 units for every 10% increase in dietary ME for combined analysis of lines and seasons. The % fat mass of total body mass increased by 0.57%, whereas % protein mass decreased by 0.21% across ME levels (R2 > 0.9). However, there was no difference (P > 0.05) in % weights (of live weight) for wings, breast filet, tenders, or leg quarters across ME levels for both lines except % fat pad that increased (P < 0.05) by 0.20% for each 10% increment in dietary ME level. Line B had higher cumulative FI, BW gain, % lean, and protein mass of body mass than line A in hot season (P < 0.05). Feed intake was not different between lines in cool season (P > 0.05), whereas higher BW and improved FCR were observed for line A. Line A had higher % fat mass in both seasons. In summary, performance and yield results as affected by dietary ME levels were line specific and were affected by grow-out seasons. The optimal dietary ME level for the ME range studied (2,800-3,000 kcal/kg) at a constant recommended amino acid level lies in determining the best performance and profitability indices by taking into account the grow-out production inputs and processing yield outputs.

Housing conditions during self-administration determine motivation for cocaine in mice following chronic social defeat stress.

RATIONALE: Stress exposure has a lasting impact on motivated behavior and can exacerbate existing vulnerabilities for developing a substance use disorder. Several models have been developed to examine how stressful experiences shape drug reward. These range from locomotor sensitization and conditioned place preference to the propensity for drug self-administration or responding to drug-predictive cues. While self-administration studies are considered to have more translational relevance, most of the studies to date have been conducted in rats. Further, many self-administration studies are conducted in single-housed animals, adding the additional stressor of social isolation. OBJECTIVES: We sought to establish how chronic social defeat stress (CSDS) and social housing conditions impact cocaine self-administration and cocaine-seeking behaviors in C57BL/6 mice. METHODS: We assessed self-administration behavior (cocaine or saline, 0.5 mg/kg/infusion) in C57BL/6 mice subjected to 10-day CSDS or in unstressed controls. Mice were housed either in pairs or in isolation during self-administration. We compared the effect of housing on acquisition of self-administration, seeking, extinction, drug-induced reinstatement, and after re-exposure to the social stressor. RESULTS: Pair-housing during self-administration revealed increased social avoidance after CSDS is associated with decreased cocaine intake. In contrast, single-housing revealed stress-sensitive cocaine intake, with increased social avoidance after CSDS associated with increased early cocaine intake. Pair-, but not single-housed mice are susceptible to drug-induced reinstatement independent of CSDS history. Stress re-exposure sensitized cocaine-seeking in stressed single-housed mice. CONCLUSIONS: The social context surrounding cocaine intake can bidirectionally influence cocaine-related behaviors after psychosocial stress and should be considered when studying stress and drug cross-sensitization.

Innate responses to gut microbiota; critical assessment of the necessary experimental controls.

The intestinal microbiota is comprises a diverse community of micro-organisms that interact with many host processes. Innate immune responses to the gut microbiota are of particular importance as they influence many other downstream responses. This fascinating host-microbe crosstalk is a rapidly expanding field of study; thus, it is critical to ensure reproducibility between studies and applicability to human clinical trials through standardization of experiments. We discuss here recent advances in the field including the spectrum of colonization statuses available, the critical importance of colonization timing, the dynamics of the microbial community, and the required housing of animals, as they pertain to appropriate experimental control and design.

Refinement of international recommendations for cubicles, based on the identification of associations between cubicle characteristics and dairy cow welfare measures.

Maladjusted cubicles for dairy cattle may cause increased skin alterations, lameness, and dirtiness. The International Commission of Agricultural and Biosystems Engineering has produced several recommendations for cubicle design, but a previous study showed that not all of them seem efficient. Here, we aim to refine and complete these recommendations. We collected data on 76 dairy farms (2,404 cows). We modeled the association between combinations of cubicle properties (e.g., type of bedding litter) and dimensions (e.g., cubicle width) relative to cow size, and prevalence of cow skin alterations, lameness, and dirtiness. We used weighted multivariable logistic regression models to predict the presence of skin alteration on the carpus; the neck, shoulder, and back; the flank, side, and udder; and the tarsus or hindquarters. We also evaluated the presence of lameness as well as the dirtiness of the lower hind legs including hocks; the hindquarters, upper hind legs, and flank; the cow rear including tail; and the udder. The risk factors highlighted led us to recommend (1) position cubicles in a way that leaves more than 1 m of clearance from any obstacle in front of the cubicle; (2) if there is an obstacle on the lateral plane (i.e., where the cubicle partition is) in front ahead of the cow, put the obstacle in front of the fore knees; (3) if there is an obstacle in front of the cow on the median plane (e.g., neck or front rail), the position the obstacle between 1.25 and 1.5 of the cow length from the curb and between 1.0 and 1.25 of its height; (4) use curb height between 0.11 and 0.15 of cow height with no sharp edges on the curb; (5) use round or at least has no sharp edges brisket board; (6) use a stone-free soil instead of concrete or use a mattress thicker than 1 cm, with microrelief, and a soft fixing area at the curb, (7) litter with straw (rather than nothing or sawdust) and keep it dry. This risk factor analysis should be followed by experiments in controlled environments to further validate these conclusions and used to update the International Commission of Agricultural and Biosystems Engineering recommendations.

Effects of early nutrition and sanitary conditions on antibody levels in early and later life of broiler chickens.

Immune maturation of broiler chickens may be affected by management, such as early life feeding strategy (early versus delayed nutrition) or by low or high sanitary conditions (LSC versus HSC). We compared systemic maternal (MAb), natural (NAb), natural auto- (NAAb), and antigen specific antibody (SpAb) levels (IgM, IgY) between broilers (n = 48 per treatment) that received early (EN) or delayed nutrition for 72 h (DN) housed in either low (LSC) or high sanitary conditions (HSC) between 7 and 35 d of age. We found minimal interactions between feeding strategy and sanitary conditions. At 7 d of age, broilers receiving EN compared with DN, had elevated levels of IgM binding keyhole limpet hemocyanin (KLH), phosphoryl-conjugated ovalbumin (PC-OVA), and muramyl dipeptide (MDP), whereas effects of feeding strategy diminished at later ages. In LSC compared with HSC broilers, levels of NAb agglutinating RRBC and sheep red blood cells (SRBC) were already elevated from 14 d of age onwards. At 33 d of age, antibody levels (NAb, NAAb, anti-LPS, anti-MDP) were all elevated in LSC, compared with HSC broilers, for both IgM and IgY, but not IgM against KLH. Western blotting revealed different binding patterns of NAAb against chicken liver homogenate, which may indicate that the NAAb repertoire is affected by antigenic pressure. Our data suggest that antibody levels are affected for an important part by environmental conditions (feeding strategy and sanitary conditions), but minimally by their interaction. However, it remains to be further studied whether the enhanced levels of antibodies as initiated by EN and LSC contribute to enhanced resistance to infectious diseases.

#Eggs: social and online media-derived perceptions of egg-laying hen housing.

Enormous quantities of data are generated through social and online media in the era of Web 2.0. Understanding consumer perceptions or demand efficiently and cost effectively remains a focus for economists, retailer/consumer sciences, and production industries. Most of the efforts to understand demand for food products rely on reports of past market performance along with survey data. Given the movement of content-generation online to lay users via social media, the potential to capture market-influencing shifts in sentiment exists in online data. This analysis presents a novel approach to studying consumer perceptions of production system attributes using eggs and laying hen housing, which have received significant attention in recent years. The housing systems cage-free and free-range had the greatest number of online hits in the searches conducted, compared with the other laying hen housing types. Less online discussion surrounded enriched cages, which were found by other methods/researchers to meet many key consumer preferences. These results, in conjunction with insights into net sentiment and words associated with different laying hen housing in online and social media, exemplify how social media listening may complement traditional methods to inform decision-makers regarding agribusiness marketing, food systems, management, and regulation. Employing web-derived data for decision-making within agrifood firms offers the opportunity for actionable insights tailored to individual businesses or products.

Rearing cage type and dietary limestone particle size: II, effects on egg production, eggshell, and bone quality in Lohmann selected Leghorn-Lite hens.

We investigated effects of rearing cage type and dietary limestone particle size (LPS) on egg production, egg weight, eggshell, and bone quality in laying hens. The pullets were reared in conventional (CON; 20 chicks/cage, 270 cm2/chick) or furnished (FUR; 30 chicks/cage; 636 cm2/chick) cages and fed 3 LPS (fine, <0.595 mm; medium, 0.595 to <1.68 mm; and 1:1 mixture of F and M wt/wt) to 16 wk of age (woa). Pullets were transitioned to laying furnished cages and retained rearing treatment combination identities (n = 5, 20 hens/cage). Hens had free access to common commercial layer diet and water through to 40 woa. Eggs were recorded daily for calculation of hen day egg production (HDEP). Subsamples of eggs laid on the first day of 24, 28, 32, 36, and 40 woa were used for eggshell quality analyses. Two hens per cage were sacrificed on the last day of 24 and 40 woa for femur and tibia quality assessments. There was no interaction (P > 0.05) between rearing cage type and dietary LPS on response variables. At 19 and 20 woa, HDEP was higher (P < 0.01) for FUR than CON reared hens but was similar (P > 0.05) afterward. At 40 woa, FUR reared hens had higher (P < 0.05) body weight (BW), egg weight (EW), eggshell thickness, and eggshell weight and tended (P < 0.10) to have higher femur and tibia mineral density (BMD) and mineral content (BMC) than CON reared hens. Rearing dietary LPS had no effect (P > 0.05) on HDEP, BW, EW, and eggshell quality. Although, rearing dietary LPS did not affect (P > 0.05) femur and tibia BMD and BMC; at 24 woa, hens reared on medium LPS tended to have higher femur BMD (0.17 vs. 0.14 g/cm2; P = 0.079) and BMC (0.99 vs.0.78 g; P = 0.088) than hens reared on fine LPS. In conclusion, hens reared in furnished cages had better eggshell quality but had marginal effects on femur and tibia quality, whereas rearing dietary LPS had no effects on eggshell and bone attributes in hens.

Heat stress impacts on broiler performance: a systematic review and meta-analysis.

Heat stress (HS) is a major problem in poultry business which affects chickens' performance and may trigger large economic losses. This study intends to analyze the impact of HS on broiler chickens' performance compared with those under normal condition. A literature search was performed on PubMed, Web of Science, and Cochrane Library for studies published in English up to January 17, 2020. Outcomes of body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR), and mortality were calculated by weighted difference (WMD) or odds ratio (OR) with 95% confidence interval (CI). A total of 12 studies with 470 broiler chickens were included. HS significantly decreased FI (11 trials: WMD = -97.95, 95% CI: -141.70, -54.20) and BWG (7 trials: WMD = -151.40, 95% CI: -198.59, -104.21) and significantly increased FCR (9 trials: WMD = 0.17, 95% CI: 0.04, 0.29) and mortality (8 trials: OR = 3.74, 95% CI: 1.39, 10.12) compared with the control. In conclusion, HS significantly affected broiler chickens' BWG, FI, FCR, and mortality, indicating the importance to control housing temperature to avoid unnecessary costs.

Effects of edible environmental enrichments during the rearing and laying periods in a littered aviary-Part 2: physical development of pullets and performance, egg quality, and carcass composition in laying hens.

Feather pecking and cannibalism are 2 major problems in laying hens' husbandry. Although additional environmental enrichment material (EM) supply is thought to lessen these problems, consistent evidences are lacking. This study examined the effects of EM supply (pecking stones and alfalfa bales) on biological performance, carcass composition, and animal losses in a littered housing system. 2,000 brown-egg and 2,000 white-egg layer hen pullets of the genetic strains Lohmann Brown classic and Lohmann Selected Leghorn classic, respectively, were reared separately in a 16-compartment aviary system until week 18. 1,320 remaining laying hens were then transferred to a 44-compartment laying stable (weeks 19-48). Both strains were tested under 4 treatment variants (n = 150-180 per strain and per variant): V1-no EM over the entire study period; V2-the rearing period with and the laying period without EM; V3-the rearing period without and the laying period with EM; V4-EM over the entire study period. Data on development, performance, egg quality, feed intake, EM consumption, animal losses, carcass composition, and economic traits were collected. Enrichment material supply during rearing (V2 and V4, both strains) was found to globally increase not only hens' relative gizzard mass (P = 0.036) but also the cracked eggs' percentage (compared with V3; P = 0.008) and to decrease the body mass in weeks 6 (P = 0.023) and 8 (P = 0.023) and the uniformity in week 16 (P = 0.011). Enrichment material provision during the laying period (V3 and V4, both strains) increased egg weights (P = 0.028) and the mean body mass (P = 0.036); however, continuous provision of EM (V4, both strains) increased the floor eggs' percentage (P = 0.019). The EM supply did not affect mortality, loss of production days, losses due to skin and toe cannibalism, or the income over feed costs. However, the income over feed and enrichment costs of V1 hens was higher by 0.55 €/hen than that of V4 hens (P = 0.022). Therefore, EM supply cannot be recommended as a measure to increase laying performance and reduce animal losses, but its positive effects on animal welfare should be considered.

Microclimate modeling in naturally ventilated dairy barns during the hot season: Checking the accuracy of forecasts.

Monitoring and predicting the microclimate in naturally ventilated barns (NVB) is important given the adverse effects of high summer temperatures on dairy cows in the context of global climate change. The aim of the work was to verify the accuracy of the microclimate forecast in a NVB using linear regression (LR). Our working hypothesis suggested that multiple periodic measurements of air temperature and relative humidity outside and inside the barns at the same time will allow us to build LR models for predicting the temperature-humidity index (THI). This was done not only for a specific dairy barn based on this indicator outside, but also in other dairy barns with a similar design, located in similar weather conditions. The results of the research indicate that the use of LR had a high accuracy of forecasting (93-96%) the THI in NVB of various designs during the summer heat. At the same time, differences were found between traits (air temperature, relative humidity as well as resulting THI) provided by meteorological weather stations and these data measured simultaneously next to the dairy barns. The proposed LR models can be used to predict THI in NVBs of different designs.