Hock Burn Research Articles

The effects of varying stocking densities during the first 10 days on the performance, welfare, slaughter and meat quality characteristics of broiler chickens in the subsequent period.

This study aimed to investigate the effects of varying stocking densities during the first 10 days on the performance, welfare, slaughter and meat quality characteristics of broiler chickens in the subsequent period (11-42 days). In the study, treatments representing 3 different stocking densities with the same group sizes were established and a total of 432 d-old chicks were used. In the first 10 days of the rearing period, treatments of 18 (SD18), 27 (SD27) and 36 (SD36) chicks per m2 were formed, and at 11 days of age, chicks in all treatments were reared at a density of 18 chicks/m2. Body weight differences in SD18, SD27 and SD36 treatments at 10 and 42 days of age were significant (P < 0.05), they were 252.6, 254.3 and 241.5g in SD18, SD27 and SD36 groups at 10 days and 2961.1, 2874.8 and 2842.7g at 42 days of age, respectively. In the first 10 days of growing period, SD36 showed a significant difference (P < 0.05) from the other groups in feed intake and feed conversion ratio, but this was not significant at slaughter age. The livability at 10 and 42 days was not different among treatments and was between 98.6 and 99.3% and 93.5-93.8%, respectively. The uniformity at 10 days was significant among the stocking density groups (P < 0.05) and the best uniformity level was obtained in the SD36 group, the differences in CV values at 42 days were not significant among the treatments. EPEF (European production efficiency factor) values were not different between the groups, the highest numerical value was determined in the SD36 group. Foot pad dermatitis, hock burn and breast burn levels were significantly higher in SD18 chickens (P < 0.05), however incidence of finger crookedness and valgus-varus deformity did not differ between the treatments. The litter moisture contents were similar between treatments, and ranged from 25.6 to 32.6%. Different stocking density treatments during the first 10 days of the experiment had no significant effect on slaughter, abdominal fat, carcass parts, color and pH values in the breast and thigh meat. In conclusion, rearing broiler chickens by dividing the poultry house area by half during the first 10 days (36 birds/m2) could help to improve the overall productivity (EPEF) by providing ease of maintenance, efficient heating and better control.

Synergistic Effects of Hydroxychloride and Organic Zinc on Performance, Carcass Characteristics, Liver and Tibia Mineral Profiles of Broiler Chickens

AbstractThis study investigated the potential synergism between hydroxychloride and organic zinc (Zn) at different levels on performance and carcass characteristics of broiler chickens. There were seven experimental diets including a negative control diet without any supplemental Zn, and six diets with 80 mg/kg added Zn in the forms of ZnSO4, hydroxychloride Zn (HCZ) and organic Zn (ORZ), and a combination of HCZ and ORZ at 40 mg/kg HCZ + 40 mg/kg ORZ (HCZ40-ORZ40), 55 mg/kg HCZ + 25 mg/kg ORZ (HCZ55-ORZ25), and 70 mg/kg HCZ + 10 mg/kg ORZ (HCZ70-ORZ10). Each diet was replicated eight times with 17 chicks per replicate. On day 35, HCZ70-ORZ10 and HCZ40-ORZ40 diets resulted in the highest body weights (P &lt; 0.05). Throughout the entire production period (1–35 days), all HCZ and ORZ diets significantly improved feed conversion ratio (FCR) compared to PC (P &lt; 0.05), with HCZ40-ORZ40 showing the lowest FCR. Breast meat yield was lower in NC-fed birds, while HCZ80 and HCZ70-ORZ10 groups had the lowest abdominal fat weight (P &lt; 0.05). Liver and gizzard weight, tibia breaking strength, and ash percentage, footpad dermatitis, and hock burns were not affected. Tibia Zn content was higher in HCZ or ORZ-supplemented birds compared to NC (P &lt; 0.05), whereas other minerals in tibia and liver were unaffected. In summary, the absence of supplemental Zn negatively affects growth and carcass characteristics, whereas replacing ZnSO4 with HCZ, ORZ, or their combinations improves bodyweight and FCR. HCZ70-ORZ10 and HCZ40-ORZ40 were identified as optimal combinations for maximizing feed efficiency.

Comparative Analysis of Animal Welfare in Three Broiler Slaughterhouses and Associated Farms with Unsatisfactory Slaughterhouse Results.

The objective of this study was to assess the health and welfare of 70 commercial broiler flocks (transport batches) in three distinct slaughterhouses based on various indicators including emaciation, dirty feathers (DFs), footpad dermatitis (FPD), hock burn (HB), breast burn (BB), breast blister, breast ulcer, ascites, septicemia/abnormal color, cellulitis, extensive traumatisms, dead on arrival (DoA) and condemnation rate. Assessment scales ranging from 0 (absence) to 2 (severe) were used for DFs, FPD, and HB, while a 0 (absence) to 1 (present) scale was applied to BB, breast blisters, and breast ulcers. The prevalence of total condemnation causes (emaciation, ascites, septicemia/abnormal color, cellulitis, and extensive traumatism) and DoA were recorded and presented in percentages. Three flocks presented condemnation rates higher than 4% and 11 flocks presented DoA rates higher than 0.5%. Twenty-one flocks achieved grade 1 (warning) for FPD and 14 achieved grade 2 for FPD (alarm). Extensive trauma was observed in 0.01% of the slaughtered animals, and no flock reached the threshold of 2%. Breast blisters and breast ulcers lesions were not observed in the studied flocks. The significant positive associations observed for the presence of severe footpad dermatitis (FPD2), severe hock burns (HB2), and breast burns (BB1) indicate simultaneous occurrences. Absences of hock burns (HB0) and breast burns (BB0) were also associated. Eleven houses that obtained the worst results for welfare indicators at slaughterhouses were audited. FPD, HB, DoA, and the condemnation rate were the most crucial indicators for identifying farms with inadequate welfare conditions. These indicators should be systematically integrated into the welfare monitoring of broilers in slaughterhouses. Audits conducted on farms detected some noncompliance with regulatory welfare standards and suggested improvements in environmental and structural conditions, as well as the reduction in stocking densities and improvements in the water systems.

Will the white blood cells tell? A potential novel tool to assess broiler chicken welfare.

This study assessed qualitative and quantitative leukocyte evaluation as potential broiler chicken welfare indicators, contributing to the limited literature on white blood cell (WBC) morphology as a diagnostic tool for welfare. Broiler chicken welfare within four poultry houses (PH) 1 to 4, each on a different farm, was assessed using on-field indicators of affective states and health, and WBC morphology was examined. Affective states were evaluated using the Qualitative Behavior Assessment (QBA), with 25 behavioral expressions scored on a visual analogue scale (VAS) and grouped into two categories. Health indicators included assessments of lameness, footpad dermatitis, dermatitis on the breast and abdominal areas, hock burn, and feather cleaning. Blood samples were collected, differential leukocyte counts were performed, and a cell score was created for the recognition, classification, and interpretation of morphologic diversity of heterophils and lymphocytes. The heterophil to lymphocyte ratio (H/L) was also determined. Descriptive statistics and generalized linear models for binomial responses were used to analyze the results. PH4 differed from the other farms, showing a higher frequency of birds within QBA group 1 ('Attentive'to 'Desperate'), while birds in PH1, PH2, and PH3 were more frequent in QBA group 2 ('Relaxed' to 'Positively occupied'). Elevated proportions of heterophils in birds from PH4 (0.61, CI95%: 0.58; 0.64) and PH3 (0.60, CI95%: 0.57; 0.63) suggested higher stress levels and inflammatory responses. Birds in PH2 and PH4 exhibited higher frequencies of health issues such as dermatitis and lameness, and higher proportions of abnormalities in WBC number and morphology. PH3 and PH4 exhibited higher H/L ratios of 3.03 and 2.58, respectively, consistent with the on-field health and behavioral indicators. Blood samples from birds in PH2 and PH4 showed a proportion of 90% toxic change in heterophils, while in PH1 and PH3 it was 70%, indicating high levels of abnormal WBC morphology across all PHs. The findings emphasize the multifactorial nature of welfare impairments, including environmental conditions, health, and affective states. This highlights the need for indicators that reflect multiple welfare impacts, such as WBC counts and morphological alterations, which can serve as powerful tools in the complex task of assessing animal welfare.

Effects of strain and stocking density on leg health, activity, and use of enrichments in conventional broiler chicken production

Conventional broiler production needs to evolve towards more animal-friendly production systems in order to meet increasing consumer concerns regarding animal welfare. Genetics and stocking density are 2 of the most promising leads to make this change possible. In this study, 6 strains with different growth rates (42-61 g/d) were reared at contrasting densities: 37 kg/m² (HD) and 29 kg/m² (LD). At the same body weight of 1.80-1.95 kg, we evaluated how growth rate and stocking density influenced broiler behaviors (general activity, interactions with enrichments), broiler health (mortality, leg problems, cleanliness and plumage growth) and litter quality. Density did not affect body weight, mortality or behaviors. For all strains, LD was associated with a lower prevalence of hock burns, a better gait score, and improved litter quality and broiler cleanliness. For the 3 strains most affected by pododermatitis, a lower prevalence was observed in LD than in HD pens. Fewer birds were inactive and more birds were standing and interacting with the enrichments (as proposed in the experiment) as soon as the growth rate was lower than that of the control strain (Ross 308). Others welfare indicators such as gait score, plumage growth improved as well. Litter humidity decreased with growth rate, contributing to better leg conditions and cleaner breasts. The prevalence of hock burns and certain behaviors (i.e., the proportion of birds grooming or walking/running) were not affected by growth rate. The proportion of birds foraging was higher at a lower growth rate. These results suggest that reducing growth rate as a preliminary measure, and reducing density as a supplementary one, would improve conventional broiler welfare.

The potential of pumice as a litter material and its influence on growth performance, carcass parameters, litter quality traits, behavior, and welfare in broiler chickens.

This study evaluated the possibilities of pumice (light stones) as litter material in broiler production. Experimental treatments included wood shavings (WS), acidic pumice (AP), and basic pumice (BP) alone, and in combination; wood shaving + acidic pumice (WSAP) and wood shaving + basic pumice (WSBP) in a ratio of 1:1. Two trials were performed, one in summer, and the other in winter. Each trial involved 750 mixed-sex Ross (308) broilers. Also, there were 15 replicate pens with 50 broilers and a stocking density of 12.5 birds/m2 for each pen at the beginning of each trial. Performance, litter quality, carcass parameters, body and leg abnormalities, body temperature, fear and stress responses, proportional asymmetry, and some behavior expressions were investigated. The litter treatment influenced the final live body weight, litter moisture, ammonia concentration, footpad dermatitis, hock burn, breast blister, hot carcass yield, heart, liver, spleen, abdominal fat, wing and neck ratio, breast and back cleanliness, and the expression of dust bathing and foraging behaviors (P < 0.01; P < 0.05). Furthermore, there was a seasonal effect on live body weight, feed conversion ratio, livability, litter pH, 42-day litter moisture, hot carcass yield, back cleanliness, footpad dermatitis, hock burn, footpad temperature, heterophil-to-lymphocyte ratio, and expression of pecking behavior (P < 0.01; P < 0.05). It is suggested that acidic pumice stone alone or in a mixture with wood shavings could be used as a reliable litter material, alternative to wood shavings.

Assessment of Welfare Problems in Broilers: Focus on Musculoskeletal Problems Associated with Their Rapid Growth.

The growth of the broiler industry has been accompanied with concerns over the environmental and social impacts on intensive production systems, as well as the welfare of the animals themselves. As a result, since the 2000s, there has been growing interest in alternative production systems that improve animal welfare and sustainability. In this context, it is important to prioritize the welfare of broilers in commercial production systems and to use reliable welfare indicators to provide consumers with information about the welfare of the animals they consume. Resource-based measures (RBM) are based on assessing the resources available to the birds in terms of their housing, environment, and management practices, such as stocking density, litter quality, lighting and air quality, etc. Outcome-based measures (OBM), also known as animal-based measures, focus on assessing the actual welfare outcomes for the birds, such as footpad dermatitis, hock burn, contamination or damage to feathers, gait score, mortality, etc. These OBM-based measures are one of the more direct indicators of welfare and can help identify any welfare issues. The present review highlighted the factors that affect animal welfare indicators focused on OBMs which can be used in the commercial broiler farms.

Effects of season, catching method, and thinning on carcass quality and production parameters in 4 different broiler production systems in the Netherlands

In the Netherlands, poultry meat production has been evolving in recent years toward broiler production systems with slow-growing broilers. In this study the effects of season, catching method, and thinning on carcass quality and production parameters in four different broiler production systems in the Netherlands was evaluated. The data for this study were collected from slaughterhouse data in 2018, 2019, and 2020 and contained information about four different broiler production systems: conventional (fast growing) broilers (CONV), 2 different indoor slow-growing broilers (SGB1 and SGB2), and Better Life 1 Star (BLS) concept with slow-growing broilers. The data set consisted of 14,976, 1,730, 3,713, and 1,121 records (flocks) for CONV, SGB1, SGB2, and BLS, respectively. All three production systems with slow-growing broilers had a lower slaughter weight, average daily gain (ADG), first-week mortality, and total mortality than CONV (no-thinning). ADG of SGB2 and BLS was lower than that of SGB1. Slaughter weight and ADG were the lowest when day-old chicks were placed in March/April and the highest when they were placed in September/October. All slow-growing broiler production systems had a lower footpad lesion score and a lower incidence of hock burns, leg hematomas, breast hematomas, dead-on-arrival chickens (DOA), and total rejects than CONV. Autumn flocks had more hock burns, a higher footpad lesion score, and more wing hematomas than spring flocks. More scabby hips and fewer total rejects were found during the summer months than during the winter months. Thinning flocks had more scabby hips, ammonia burns, and DOAs and fewer hock burns, footpad lesions, wing hematomas, leg hematomas, breast hematomas, and total rejects than no-thinning flocks. Mechanically caught flocks had more ammonia burns, DOAs, and total rejects than manually caught flocks. In conclusion, this study showed that all three production systems with slow-growing broilers had a lower first-week mortality and total mortality and better scores on most carcass quality parameters and welfare indicators than CONV.

Effects of Salvinia as a broiler litter material on growth performance, behavior, welfare parameters, litter characters, and ammonia emission

The type of litter material has direct impacts on production, behavioral, and welfare parameters of broilers. The price of conventionally-used litter materials is increasing. Salvinia molesta is a fast-growing aquatic plant which has become an environmental issue in some areas. This study assessed the suitability of air-dried Salvinia plants (SAL) as an alternate litter material to paddy husk (PH). Resulting in a completely randomized experiment, a total of 240 broilers was raised in 12 floor-pens each provided with either PH or SAL as litter materials, from 11 to 36 d. Scan sampling technique was employed to record the birds' engagement in 15 predetermined behaviors. Foot pad dermatitis (FPD), hock burn damage (HBD) and plumage cleanliness (PC) were assessed using Welfare Quality Scoring System. Litter samples were analyzed for pH, dry matter%, water holding capacity, porosity, N%, tapped-density and ammonia emission rate. The litter material had no significant effect (P > 0.05) on mortality, growth performance parameters, dressing % and visceral organ weight. The scores for FPD and PC were unaffected by the litter materials. SAL litter reported significantly lower (P < 0.05) HBD scores. The percentages of birds engaged in eating and wing flapping behaviors were significantly lower on SAL. Litter type had no significant influence on the color, aroma, flavor, texture and overall acceptability of breast meat. Air-dried Salvinia plants reported acidic pH. SAL litter gave a significantly higher tapped-density. Ammonia emission rate of SAL litter was significantly lower than that of PH. However, the final litter N content was higher for PH (3.7%) than SAL (3.2%). The study proposes air-dried Salvinia plants as a litter material for broilers since it gives growth performance comparable to PH with reduced hock burn damage incidences. Effects of SAL on behavior and the fertilizer value of the spent litter are to be studied further.

Research Note: Welfare and stress responses of broiler chickens raised in conventional and animal welfare-certified broiler farms

The present study was conducted to assess the animal welfare status of broiler chickens raised in conventional and welfare-certified farms. One conventional farm (30,000 birds/house, 1,488 m2/house, 2 houses) and one animal welfare-certified farm (32,000 birds/house, 1,920 m2/house, 2 houses) were selected to measure productivity, stress responses, and animal welfare indicators in 3 broiler flocks (2 farms/season, n = 6 flocks/farm type) during summer, autumn, and spring. Upon farm visits, body weight, uniformity, and animal welfare indicators (i.e., fecal and feather corticosterone, footpad dermatitis, hock burn, feather dirtiness, and gait score) were measured at 26 d posthatch. Also, moisture, nitrogen, and pH of litter, light intensity, ammonia concentration, and body surface temperature of head, chest, and legs were measured. There was no difference in body weight and uniformity between farm types. Fecal corticosterone concentrations were higher (P = 0.021) in welfare-certified vs. conventional farm, but no significant difference was found in feather corticosterone. Welfare-certified vs. conventional farm had lower percentages of hock burn (P = 0.018), feather dirtiness scores (P = 0.009), and gait score (P = 0.040), and there was no difference in footpad dermatitis. Nitrogen content in litter samples tended to be higher in conventional vs. welfare-certified farms (P = 0.094), and there was no difference in moisture and pH between farm types. Ammonia concentration within the broiler houses was not different between 2 farms. However, animal welfare farm was found to be brighter than conventional farm (P < 0.001). The body surface temperature of head, chest, and legs was not different between farm types. In conclusion, the welfare-certified farm had higher welfare measures, including lower hock burn, feather dirtiness, and gait score, confirming an overall improvement in welfare indicators. However, the observation on the elevated feather corticosterone noted in welfare vs. conventionally raised chickens warrants further studies.

Effects of pre-heating of broiler breeder's eggs on hatchability, chick quality, overall performance, and welfare traits in broilers.

This study aimed to investigate the effects of varying pre-heating practices (12-h: PH12; 8-h: PH8; 4-h: PH4 and 0-h or no pre-heating: PH0) of broiler breeder's eggs prior to incubation on hatching, chick quality, overall performance, and welfare traits in broilers. A total of 960 eggs obtained from Ross 308 breeders at 45 weeks were used for pre-heating manipulations and 480 chicks for broiler experiment. Apparent fertility was higher in PH0 (94.6%) and PH4 (94.5%) treatments than in PH8 (91.6%) and PH12 (90.6%); hatchability of fertile and set eggs was higher in PH4 and PH12. PH4, PH8, and PH12 treatments significantly accelerated the average hatching time compared to PH0. General chick quality was not affected by pre-heating treatments. However, chick length was significantly lower in PH0 chicks than PH12. Pre-heating manipulations did not change the overall broiler performance. Welfare characteristics were similar among treatments, while only hock burn was better in PH8 broilers. In conclusion, pre-heating of broiler breeder eggs for 4 to 12 h improved hatching success by lowering embryonic mortality and shortened the average hatching time compared to no pre-heating, and did not cause any significant alteration in chick quality, overall performance, and welfare characteristics.

Effects of grain-based pecking blocks on productivity and welfare indicators in commercial broiler chickens.

This experiment was conducted to investigate the effect of grain-based pecking blocks on productivity and welfare status at two commercial broiler welfare-certified farms. Production and welfare indicators were assessed at two farms (designated Farm A and B). Both farms had two windowless houses with forced tunnel-type ventilation and housed broilers at stocking densities of approximately 16.7 birds/m2 (Farm A) and 16.8 birds/m2 (Farm B). Each house was divided into two or three equal sections and was provided with or without pecking blocks. Grain-based pecking blocks, measuring 25 × 25 × 25 cm, were given to broilers in both farms at 1 block per 1,000 birds. Various parameters including productivity (body weight and flock uniformity), corticosterone levels (in fecal droppings and feathers), footpad dermatitis, hock burn, feather dirtiness, gait score, litter quality, body surface temperature, and volatile fatty acids in fecal samples were assessed at 26 days of age, whereas litter quality was analyzed at 13 and 26 days of age. There were no significant effects of providing pecking blocks on productivity (body weight and uniformity), fecal and feather corticosterone, welfare indicators (i.e., footpad dermatitis, hock burn, feather cleanliness, and gait score), and litter quality (i.e., moisture, nitrogen, and pH). No differences in body surface temperature between the control and enrichment treatments were noted in Farm B, but body surface temperatures of the head (p = 0.029) and legs (p = 0.011) in the enrichment vs. control group were elevated in Farm A. Butyrate concentration in the enrichment vs control group was higher in Farm B (p = 0.023), but this effect was not detected in Farm A. It is concluded that grain-based pecking blocks did not affect performance and welfare indicators. Further studies are warranted to elucidate the potential impact of grain-based pecking blocks on gut health indicators.

The Effect of Season on the Performance, Health, and Welfare of Broilers

The research was carried out on 80 broiler flocks (Ross 308) raised during the winter, spring, summer, and autumn seasons in commercial enterprises in Uşak City Center and its districts engaged in contract farming. Broiler flocks were examined weekly during the 0-42 day growth period for body weight, weight gain, feed consumption, feed conversion ratio, mortality and EPEF. The 42-day-old broiler was scored for FPD and HB. The season significantly impacted the broiler flock's performance and the birds' prevalence with FPD and HB under commercial conditions. Spring and autumn flocks showed higher performance than winter and summer flocks. The prevalence of birds with foot pad burn and hock burn was highest in winter flocks and lowest in summer flocks. These findings indicate that seasons can significantly impact broiler farms' economic performance and bird welfare. As a result, obtaining further information about the positive and negative effects of seasons on broilers can promote production and provide critical data to encourage innovative strategies for sustainable flock management and improve broiler industry compliance with animal welfare standards.

Dietary strategies can increase cloacal endotoxin levels and modulate the resident microbiota in broiler chickens

Endotoxins released from poultry feces have been associated with impaired human health. Because endotoxins are released from gram-negative intestinal bacteria, it was hypothesized that dietary strategies may influence endotoxin excretion via modulation of gut microbiota. We therefore tested dietary strategies that could potentially reduce cloacal endotoxin levels in broiler chickens. One-day-old male Ross 308 (N = 1,344) broilers were housed in 48 pens (N = 8 pens/treatment, 28 chickens per pen) and fed 1 of 6 diets for 35 days (d) in a 3-phase feeding program: a basic diet (CON) that served as the reference diet, or basic diet supplemented with butyrate (BUT), inulin (INU), medium-chain fatty acids (MCFA) or Original XPC™LS (XPC), or a high-fiber-low-protein (HF-LP) diet. A significant (P < 0.05) increase in cloacal endotoxin concentration at d 35 was observed in BUT as compared to CON. Analysis of cloacal microbiota showed a trend (P < 0.07) for a higher gram-negative/gram-positive ratio and for a higher relative abundance of gram-negative bacteria at d 35 (P ≤ 0.08) in BUT and HF-LP as compared to CON. A significant (P < 0.05) increase in average daily gain (ADG) and improved feed conversion ratio (P < 0.05) were observed in MCFA during the grower phase (d 14-28), and a significant (P < 0.05) increase in average daily feed intake (ADFI) was observed in MCFA during d 0 to 28. Broilers fed HF-LP had a significantly (P < 0.05) higher FCR and lower ADG throughout the rearing period. No treatment effects were found on footpad dermatitis, but BUT had worst hock burn scores at d 35 (P < 0.01) and MCFA had worst cleanliness scores at d 21 but not at d 35 (treatment*age P < 0.05), while INU had better cleanliness as compared to CON at d 35 (P < 0.05). In conclusion, especially BUT and HF-LP were able to modulate resident microbiota and BUT also increased cloacal endotoxin levels, which was opposite to our hypothesis. The present study indicates that cloacal endotoxin release can be affected by the diet but further study is needed to find dietary treatments that can reduce cloacal endotoxin release.

152 Leveraging Rfid Technology to Investigate the Genetic Associations Between Feeding Behavior and Leg Health in Floor-Raised Broilers

Abstract Leg disorders (LD) pose serious welfare issues in broiler chickens. The objective of this study was to investigate the suitability of using feeding behavior (FB) traits as potential leg health indicators in floor-raised broilers. The data used were recorded from 95,711 pure-line chickens of both sexes. The individual FB was monitored continuously on a feeder visit basis with a radio-frequency antenna system. The visit-log data were clustered into daily observations for different FB traits and averaged for the 1st week period after the trial started. The FB traits were daily feed intake (DFI1), number of visits (NV1), time spent at the feeder (TSF1), visiting activity interval (VAI1), number of visited feeders (NVF1), and walked distance visiting feeders (WD1). The LD traits were tibial dyschondroplasia (TD), hock-burn (HB), footpad (FP), rotated legs (RO), bowed-in (BI), and bowed-out (BO) leg structure deformities. Multi-trait linear-threshold models were fitted using Bayesian inference for estimating (co)variance components. The heritability (h2) posterior averages and standard deviations (within parentheses) ranged between 0.09 (0.01) and 0.52 (0.03) for LD traits, and between 0.09 (0.01) and 0.47 (0.02) for FB traits. Genetic correlations (rg) between FB and LD traits ranged from null to weak. TD presented negative rg with NV1 (-0.13), TSF1 (-0.14), NVF1 (-0.11), and WD1 (-0.14), indicating that some alleles involved in broiler activity are favorably associated with a potential reduction in the risk of TD-caused bone lesions. Conversely, FP presented unfavorable rg with the same traits (ranging from 0.21 to 0.32), except for TSF1 (-0.08). When compared with the remaining FB traits, DFI1 generally presented the opposite relationships with TD and FP, with positive (0.16) and negative (-0.18) genetic correlations observed for the first and the latter, respectively. Angular and rotational deformities (RO, BI, and BO) did not present significant correlations with FB traits, apart from the weak correlation found between BO and TSF1 (0.11). General activity indicators such as NV1, NVF1, and WD1 could represent earlier selection criteria to reduce TD incidence, although the potential undesired selection response for FP must be further investigated.

Use of coffee husks – comparison of pellet bedding quality, performance features, and some welfare indicators of broiler chickens

BackgroundThe study aimed to evaluate the influence of wheat straw and different coffee husk (CHs) levels in pellet bedding on its quality, broiler chickens’ performance, meat quality, and welfare indicators. In total, 200 Ross 308 chickens were divided into 4 groups: C – control with wheat straw pellet; CH10 – pellet with 10% CHs, CH25 – pellet with 25% CHs, and CH50 – pellet with 50% CHs. During 42 days of rearing, each bedding's physicochemical features were analyzed. The production results were controlled, and the footpad dermatitis, hock burns, and feather quality were assessed. From chosen birds, carcass composition was analyzed, as well as the qualitative features (color, water-holding capacity, drip loss) and breaking bone strength.ResultsThe bedding material and rearing days influenced the content of dry matter, crude fiber, nitrogen, phosphorus, potassium, NDF, ADF, and pH. The results were inconclusive. The increasing trends in nitrogen, phosphorus, and potassium content were noticed at the end of rearing. Strong coefficient determination in bedding features was found (0.580 – 0.986). The pellet with CHs had no adverse effect on the growth performance of broilers. In the CH50 group, a lower fat percentage was found. A beneficial effect on water-holding capacity was noticed in leg muscles from CH10 and pectoral muscles from CH25. A significant decrease was found in footpad dermatitis incidence in groups CH25 and CH50.ConclusionsIt can be concluded that CHs reuse in broilers as the pellet bedding material is possible due to the beneficial effect on some meat quality features and no adverse effect on the performance of broiler chickens. The positive impact on lower foot pad dermatitis incidence indicated the possibility of using CHs in pellet bedding.

Leg health and growth performance of broiler chickens supplemented with grape seed extract

Background: Active bone remodeling processes can be altered by the presence of reactive oxygen species and, therefore, cause leg problems in broiler chickens. The antioxidant activity present in grape seed extract (GSE) could be a viable alternative to high inclusion levels of vitamin E (VE) as a nutritional strategy to improve the antioxidant capacity of birds and, thus, prevent leg abnormalities. Objective: To evaluate the effect of partial substitution of VE with grape GSE on leg health and performance of broiler chickens. Methods: Four hundred and twenty newly-hatched Ross 308 male broiler chickens were distributed into three treatments: 1) Control-AL, a diet containing 40 IU/kg of VE and fed ad libitum (CAL); 2) Control-FR, the CAL diet but offered through a feed restriction program (CFR); and 3) grape seed extract-AL, a diet containing 10 mg/kg of GSE + 10 IU/kg of VE fed ad libitum (GSE-AL). The trial was conducted for 47 days. Feed intake and body weight of the chickens were recorded weekly to evaluate performance. At day 43, gait score (GS), valgus/varus angulation (AngV), foot burn (FB), and hock burn (HB) lesions were evaluated. At day 47, tibia-breaking strength (TBS) and gastrocnemius tendon-breaking strength (GTBS) were evaluated. Results: Birds in the GSE-AL treatment showed reduced (p≤0.05) GS compared to the other treatments. No statistical differences (p&gt;0.05) were found in AngV, HB, FB, TBS, TGBS, and growth performance among treatments. Conclusions: These results suggest that GSE may partially replace VE in broiler diets without negative effects on growth performance or leg health. Further research is required to evaluate the potential of grape seed extract to replace VE or other ingredients with antioxidant activity under different rearing conditions and feeding programs.

The Type of Floor and its Impact on the Growth, Physiological and Performance of Broilers

This study was conducted to find out the effect of floor type on the growth, some physiological characteristics and welfare standards for broilers. 120 unsexed one-day-old ROSS 308 broiler chicks were used. The study included two groups with three replicates (20 birds for each replicate). The first treatment, the birds were raised on the Rice husks litter, and the second treatment the birds were raised on a wire floor, 15 cm high. Feed and water were provided freely throughout the study period. The results showed that raising broilers on different floor type did not show significant differences in body weight, weight gain rate and feed conversion factor between groups, and significant differences were found in feed consumption in favor of the second treatment at the age of 21 days, and no significant differences appeared in the standards of productive performance. for broilers at the age of 38 days, and there were no significant differences in the percentage of dressing, the relative weight of the internal organs and the concentration of ammonia NH3 gas, while rearing on the wire floor reduced the concentration of carbon dioxide Co2 and raised the body temperature of the birds raised on the wire floor, there was a significant improvement in measures of well-being, the incidence of inflammation of the hock burn and footpad dermatitis. The biochemical and hormonal characteristics were not significantly affected when raising birds on wire floor, and there was an improvement in the level of antioxidants in the bird’s body through an increase in GSH. We conclude from this study that raising broilers on the wire floor did not affect the productive performance, but it improved the status of antioxidants and welfare standards for broilers.

Impact Light Regimen and Melatonin on Growth Performance, Welfare and Physiological Parameters of Broiler Chickens

The study was conducted to evaluate the effects of lighting program and melatonin on growth performance, welfare, and some physiological characteristics of broilers. A completely randomized design involved 2 photoperiods (constant lighting 24 L:0 D). and intermittent lighting 4 L:2 D) periodically for group one and two respectively, the third group the birds were to continuous lighting 24 hours with the addition of the melatonin 20 mg/kg of diet. A total of 180 unsexed one-day-old ROSS 308 broiler chicks randomly divided into three treatments with three replicates (20 birds per replicate). The results showed a significant superiority in the body weight and weight Gain of the intermittent light treatments and the addition of melatonin compared to the control treatment for broilers at 21 days. No significant differences in growth performance for broilers at 38 days, and there were no significant differences in dressing percentage, relative weight of the internal organs, temperature of the bird’s body parts, biochemical characteristics, and hormones, except for the significant decrease in the level of ALT for birds treated with melatonin and when raising birds under a lighting program. Intermittently, there was an improvement in the level of antioxidants through a decrease in MDA. There was a significant improvement in the measures of welfare, as the incidence of inflammation of the hock burn and Footpad dermatitis decreased. Results above suggest that the raising broilers under intermittent lighting system and treatment with melatonin did not affect production performance, but it improved the status of antioxidants and welfare Indications for broilers.

An automatic classifier for monitoring applied behaviors of cage-free laying hens with deep learning

Poultry behavior is an important indicator of their welfare, health, and production performance. The welfare of layers and broilers such as walking ability, breast blisters, hock burn, and heart failures are measurable through behavior monitoring. In the previous research, most of laying hen studies focused on basic behaviors such as drinking, feeding, and walking of broilers. However, with the transition to the cage-free houses, more natural behaviors need to be monitored for welfare assessment. In this study, a six-behavioral classifier (i.e., feeding, drinking, walking, perch, dust bathing, and nesting) was developed based on multiple CNN models (e.g., efficientNetV2 and YOLOv5-cls). The classifier is one of the first model included perching, dust bathing, and nesting behaviors, which are special characters that reflect basic welfare of cage-free birds. Furthermore, a cage-free birds’ dataset containing 12,000 pictures was collected and annotated in a lifespan scale (e.g., from 1 week to 50 weeks of old), from which 9,600 images were used as training dataset and the rest were used for validation. The best performance model YOLOv5-cls-m achieved an average accuracy of 95.3%, which is 5.01% higher than that of efficientNetV2-l. Drinking behavior of chicks was monitored with the highest accuracy (97.8%) while nesting behavior had a detection precision of 92.5%. In terms of chickens’ age, the classifier has a better accuracy for smaller chicks (< 10 days) than larger chickens older than 10 days (96.4% vs 94.3%). The results show that the classifier is a useful tool to segregate cage-free bird behaviors in various life periods and environments.