British Poultry Science最新文献

1. Machine-vision-based chicken counting is a highly efficient approach. Nonetheless, in scenarios with high breeding densities, chickens in the captured images frequently overlap with one another. This research addressed the challenge of accurately counting chickens within a free-range chicken coop in densely environments. It proposes a chicken-counting network specifically designed for dense scenarios, namely MFSnet.2. The study extracted multi-scale feature maps and subjected them to processing during the fusion stage via a Feature Screening Module (FSM). This module generated feature maps that were richly endowed with features from diverse scales to enhance information, thereby augmenting the network's capacity to accurately identify chickens.3. The dataset was collected and labelled and denominated as Chicken2023. It consisted of 550 images, which, in aggregate, encompassed a total of 49 747 chickens. To validate its efficacy, it was compared with extant counting algorithms. The experimental findings derived from the Chicken2023 dataset illustrated that this method attained a better counting performance level. It achieved a mean absolute error (MAE) of 2.7 and a root mean square error (RMSE) of 3.6. When juxtaposed with the top-performing network, it showed a notable improvement, with a 6.25% reduction in MAE and a 6.26% reduction in RMSE.4. The network model proposed in this study accurately recognised the number of chickens in dense environments and improved the efficiency of poultry farming.

1. This study investigated the potential of using waste chicken skin as a sustainable alternative to produce functional and healthy flavour enhancers. For this purpose, flavour enhancer products were developed using fat obtained from waste chicken skin, refined chicken skin fat, and fat rich in polyunsaturated fatty acids (PUFA) obtained by fractionation of this fat and fats enriched in conjugated linoleic acid (CLA) by photoisomerisation.2. Sensory analysis revealed that flavour enhancers produced with fats rich in PUFA and CLA exhibited properties similar to traditional chicken bouillon. In addition, it was determined that the produced flavour enhancers had lower salt and energy content. These products contained up to 40% less SFA and 100% more PUFA than traditional bouillon. Flavour enhancers with more than 30% total CLA isomers could be produced.3. The results showed a healthy and environmentally friendly functional flavour enhancer production with high consumer acceptability.

1. Indian backyard chicken breeds are well adapted to local climatic conditions and possess distinct genetic characteristics, necessitating a dedicated SNP chip to address their unique genetic diversity, breed identification and conservation needs. In this study, a high-density SNP chip, Axiom_Kukkut was developed with SNP markers derived from genomes of 16 indigenous chicken breeds, Red Jungle Fowl and White Leghorn.2. A total of 622,376 markers and an inter-marker distance of 1.9 kb, the Axiom_Kukkut provided a denser marker distribution compared to existing arrays. The chip was validated by genotyping a set of samples from diverse Indian chicken breeds. All the SNPs were used for validation. An average call rate of 99.92% and 91.28%, as high resolution polymorphic markers, demonstrated the high precision of the designed array.3. Population stratification analysis revealed high genetic diversity and distinct linkage disequilibrium patterns among various breeds. Multivariate principal component analysis confirmed the genetic distinctiveness of Red Jungle Fowl and Uttara, suggesting low genetic diversity due to geographic isolation or specific breeding practices.4. The customised SNP chip allows a multitude of possibilities, including applications in genome-wide association analysis, identification of selection signatures, population genetics and breed improvement programmes for Indian chicken. Continued refinement will expand its utility to include exotic and commercial breeds as well, enhancing its overall applicability across a wider range of chicken populations.

1. This study investigated the effect of Erycibe obtusifolia Benth (EOB) plant residue on welfare, stress-related gene expression as well as microorganisms of both the gut and bedding materials of chickens.2. In this study, a total of 160, bearded chickens aged 80 d old were raised on four bedding types: EOB, rice husk (RH), EOB and RH bedding (EOB E) and EOB plus Enterococcus faecalis fermented bedding (RHEOB). Twelve behaviours, foot pad dermatitis and feather condition of each group were observed, caecal contents and bedding material were collected for microorganisms detection and brain tissues were collected for gene expression related to fear, stress and aggressive behaviour.3. Bedding had no effect on foot pad dermatitis (FPD), feather condition or abnormal behaviour. Sand bathing (p <0.05) and affinity behaviour (p <0.05) increased in birds on the EOB with rice husk bedding material. The expressions of 5-HT, HTR1A and CRH genes in brain tissue were affected by different bedding types. The mixture of EOB and rice husk reduced the relative abundance of Brevibacterium, Enterococcus and Streptococcus spp. increased the relative abundance of probiotics of Rombutz, Lactobacillus spp. and L. mucosus and improved the microflora of the bedding and caecal contents.4. EOB bedding showed good application, as EOB and rice husk mixed bedding had the best effect.

1. An experiment was conducted to study the effects of supplementing calcitriol (CT) on performance and bone mineralisation in broilers (1-42 d) fed a calcium and available phosphorus (Ca-aP)-deficient diet. The CT (10 mg/kg 1,25-di-OH-VitD3) was derived from Solanum glaucophyllum leaf.2. A control diet (CD) with the recommended (Cobb 400) levels of Ca (9.4, 9.2 and 8.8 g/kg) and aP (4.5, 4.2 and 4 g/kg, respectively, in starter, grower and finisher) was prepared. Six experimental diets were prepared, which include two reduced diets (RD) formulated with 80% (R80) and 70% (R70) of the recommended levels of Ca and aP. Both RDs were supplemented with three levels of CT (0, 1 and 2 µg/kg). Each diet was offered ad libitum to 10 replicate pens (198 × 122 cm) containing 25 male broilers each from 1 to 42 d of age.3. Body weight gain (BWG) and feed conversion (FCE) were recorded bi-weekly. The degree of hock joint deformity was measured as leg abnormality score (LAS) and concentrations of Ca and P in serum were analysed on d 43. The right tibia was analysed for total ash, Ca and P in tibia ash.4. The BWG was not affected by either the reduction of Ca and aP or the supplementation of CD to the RD. Similarly, FCE was not affected by reducing the Ca and aP to 80%, while at 70%, the FCE was reduced compared to the CD group. Supplementation with CT significantly improved the FCE similar to the CD group during the starter phase and overall period (1-42 d).5. The LAS increased and bone minerals (as tibia ash and its Ca and P contents) reduced in broilers fed both RD. Supplementation with CT at 2 µg/kg significantly reduced LAS and improved the bone mineral variables similar to those fed the CD.6. Dietary Ca and aP levels can be reduced to 70% of the dietary recommendations for the broiler breed with supplementation of calcitriol at 2 µg/kg without affecting the performance and bone mineralisation.

1. This research characterised cell-free supernatants (CFS) obtained from lactic acid bacteria (Leuconostoc pseudomesenteroides T139, Pediococcus acidilactici T115 and Streptococcus thermophilus T127) and examined the effects of CFS (10%) on the safety and quality of poultry meat stored at 4°C for 7 d.2. In the first stage of the study, metabolite production (exopolysaccharide, hydrogen peroxide and diacetyl production) and their bioactive properties (pH values, total acidity, total phenolic contents and antioxidant activities) were detected. In the second stage, poultry meat was inoculated with Escherichia coli O157:H7, Listeria monocytogenes and Salmonella Typhimurium (≈5 log CFU/g) using the spot inoculation method and the counts of pathogens were examined. In the final stage of the study, the counts of background microbiota (total mesophilic aerobic bacteria, total psychrophilic aerobic bacteria, Pseudomonas spp. Enterobacteriaceae and lactic acid bacteria) were determined.3. The amounts of exopolysaccharide, hydrogen peroxide and diacetyl were in the range of 156.00-514.30 µg/ml, 0.01-0.07 µg/ml and 19.15-75.54 ng/ml, respectively. The pH values, total acidity, total phenolic contents and antioxidant activities (DPPH and ABTS⁺ radical scavenging activities) of the CFS were in the range of 4.08-4.34, 1.78-1.87 g lactic acid/100 ml, 3549-3864 mg GAE/l, 30.42-37.76% and 21.78-31.41%, respectively. In the second stage of the study, the counts of E. coli O157:H7, L. monocytogenes and S. Typhimurium inoculated on poultry meats were reduced by CFS treatment in the range of 0.82-1.41, 0.77-2.11 and 0.71-1.78 log CFU/g, respectively. In the final stage of the study, the counts of background microbiota on CFS-treated poultry meat samples were efficiently decreased during storage period (4°C for 7 d).4. The current study revealed that CFS are highly effective for ensuring meat safety and improving quality.

1. The purpose of this study was to investigate the effects of different metabolisable energy (ME) and crude protein (CP) levels on the growth performance, serum biochemical indices, and intestinal development of pigeon squabs.2. A total of 324, 12 d old squabs were used and fed one of three ME (13, 12.5 and 12 MJ/kg) and three CP levels (18, 17 and 16%) to give nine experimental diets with six replicates each containing six birds (n = 6).3. Body weight of squabs at 28 d of age were the highest in group 3 (13 MJ/kg ME, 16% CP). Increasing ME or CP levels significantly elevated the relative weight of abdominal fat of squabs.4. A higher ME level in the diet induces higher serum content of total cholesterol and low-density lipoprotein, and greater levels of aspartate aminotransferase activity in 28 d old squabs. Compared with lower CP (16%) treatment, 18% dietary CP significantly increased the contents of serum urea nitrogen and uric acid. Duodenal villus length and pancreatic trypsin activity were the greatest in diet 3.5. The optimal dietary energy and protein levels of artificial crop milk for pigeon squabs in the late stage of growth were 13 MJ/kg ME and 16% CP from days 12-28 of age.

1. Infections due to Campylobacter spp. significantly contribute to bacterial gastroenteritis worldwide. This study aimed to investigate whether Campylobacter spp. can persist in poultry environments and how they survive in various sources from poultry farms and slaughterhouses.2. A total of 192 samples were collected from three different poultry farms and slaughterhouses and C. jejuni was detected in 47.4% of them. The prevalence of C. jejuni was higher in poultry slaughterhouses than in farms. A total of 69 C. jejuni were tested for their susceptibility to different antibiotics. From these 15 isolates from poultry farms and slaughterhouses, 50-70% exhibited antibiotic resistance. These isolates were analysed for plasmid profiling, identification of virulence genes and lipo-oligosaccharide characterisation.3. Nearly all C. jejuni isolates harboured plasmid sizes ranging from 2.3 to 23 kb. The virB11 gene of C. jejuni was characterised using PCR and there was no gene amplification in the isolated strains. All multidrug-resistant (MDR) isolates from poultry farms and slaughterhouses had full-length lipo-oligosaccharide molecules, based on their molecular weight.4. The MDR strain C. jejuni (LCJ5) was chosen for its survival rate from various sources, including lamb, chicken meat and eggs, as well as in the slaughterhouse environment, which contains materials like stainless steel, iron and wood. The findings suggested that the prevalence of Campylobacter can be reduced through improved hygiene practices and by raising awareness about the importance of consuming properly cooked meat products.

1. The influence of different inclusion levels of a bioactive peptide derived from cottonseed meal by enzymatic hydrolysis was examined in broilers. Experimental diets contained six inclusion levels of cottonseed bioactive peptides (CBP) at 0, 2.5, 5, 10, 15 and 20 g/kg of diet. A total number of 432, one-day-old broiler chicks (Ross 308) were randomly allocated to one of six treatments, which were replicated six times based on a completely randomised design.2. The results showed that CBP in the diet linearly increased body weight gain feed consumption and so FCR. As a result of the higher feed intake, CBP linearly (p < 0.05) increased FCR. However, when corrected for the body weight differences (d 35), there was no significant effect of CBP on FCR.3. The CBP inclusion improved crude protein and Arg, His and Met ileal digestibility in a linear manner (p < 0.01). Serum concentration of Lys, Trp, Ala and Orn decreased linearly (p < 0.05) as the concentration of CBP increased in the diet.4. Antibody titres against Newcastle disease, sheep red blood cell (SRBC) and serum concentration of IgY, IgM, IgA and GSH, red blood cell count and haematocrit increased in line with CBP inclusion.5. There was both a linear (p = 0.001) and quadratic (p = 0.021) response for carcase yield percentage, although the liver's relative weight linearly (p = 0.001) decreased with higher CBP inclusion.6. Overall, the data showed that dietary supplementation of CBP in broiler diets has the potential to improve performance traits, ileal protein and amino acid digestibility and can be used as a novel functional protein in poultry diets.

1. This study evaluated the effects of zinc methionine (Zn-met) and selenium (Se) yeast on growth performance, antioxidant capacity, immune function and intestinal morphology of broiler chickens under heat stress (HS).2. A total of 54, yellow-feather male broilers (35-d old) were randomly allocated to one of three groups; a control group (CON) fed a basal diet and maintained at 26 ± 1°C, a group fed the basal diet with cyclic HS alone or + Zn-met + Se yeast group (HZS) fed a basal diet supplemented with 250 mg/kg Zn-met and 150 mg/kg Se yeast. After the 7-d prep-trial period, the birds in the HS and the HZS groups were exposed to cyclic HS treatment (30 ± 1 to 34 ± 1°C) from d 8 for 2 weeks.3. The HS treated birds had reduced body weight, daily gain, feed intake and feed conversion ratio (p < 0.01) and increased mortality and rectal temperature, whereas the HZS group had a lower mortality rate and rectal temperature. The HS group had higher blood triglyceride (p < 0.01) and lower potassium (0.05) levels than the CON group. Exposure to HS increased the lipopolysaccharide levels (p < 0.05) and decreased the levels of immunoglobulin (Ig) A and IgG (p < 0.05), which were improved in the HZS group. The HZS group reversed the increase in blood catalase activity caused by heat stress and increased glutathione peroxidase levels (p < 0.05). Heat stress decreased villus height in the duodenum and jejunum, increased the crypt depth and decreased the villus height to crypt depth ratio in the small intestine, which were improved in the HZS group (p < 0.05).4. Dietary supplementation with Zn-met and Se yeast was shown to be an effective nutritional regulation strategy for alleviating any negative effects of heat stress in broiler performance.