Journal of Poultry Science最新文献

{"title":"Combinatorial Effect of Dietary Oregano Extracts and 3,4,5-Trihydroxy Benzoic Acid on Growth Performance and Elimination of Coccidiosis in Broiler Chickens.","authors":"Shan Randima Nawarathne, Dong-Myung Kim, Hyun-Min Cho, Junseon Hong, Yubin Kim, Myunghwan Yu, Young-Joo Yi, Hans Lee, Vannie Wan, Noele Kai Jing Ng, Chuan Hao Tan, Jung-Min Heo","doi":"10.2141/jpsa.0210116","DOIUrl":"10.2141/jpsa.0210116","url":null,"abstract":"<p><p>We aimed to compare the combinatorial effect of 3,4,5-trihydroxybenzoic acid (THB) and oregano extracts (OE) with THB alone on the growth performance and elimination of deleterious effects in coccidiosis-infected broilers. A total of 210 one-day-old broilers were randomly assigned to one of five dietary treatments, with six replicates each, for 35 days. Dietary treatments were: 1) non-challenged, non-treated (NC); 2) challenged, non-treated (PC); 3) PC+ Salinomycin (0.05 g/kg; AB); 4) PC+THB (0.1 g/kg; THB); and 5) PC+THB+OE (0.1 g/kg; COM). On day 14, all groups except for NC were challenged with a 10-fold dose of Livacox^® T anticoccidial vaccine to induce mild coccidiosis. All treatments significantly improved (<i>P</i><0.05) body weight, average daily gain, and average daily feed intake, compared to PC, on days 21, 28, and 35. However, all treatments significantly reduced (<i>P</i><0.05) the feed conversion ratio of PC by more than 14.60% on day 35, 11.76% during growing period, and 10.36% through the entire period. Broilers receiving anticoccidial treatments had 54.23% and 51.86% lower lesion scores (<i>P</i><0.05) at 4 and 7 days post-infection, respectively, compared to PC. Additionally, the villus height of COM was significantly longer (<i>P</i> < 0.05) than that of THB. Although the molecular action of COM remains unclear, OE addition to THB reduced the shedding of oocysts better than THB alone (<i>P</i><0.05, 9-11 days post-infection). Most importantly, COM effectively minimized the mortality of challenged birds from as high as 11.90% (PC) to 0%, a level similar to NC and AB, while THB maintained a mortality of 2.38%. In conclusion, the anticoccidial effect of THB can be enhanced by the addition of OE for better animal performance and the elimination of deleterious effects from coccidiosis-infected broilers for 35 days.</p>","PeriodicalId":16883,"journal":{"name":"Journal of Poultry Science","volume":"59 3","pages":"233-246"},"PeriodicalIF":1.8,"publicationDate":"2022-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/8a/b2/jpsa-59-233.PMC9346594.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40413593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Increasing Stocking Density on the Performance and Ileal Microbiota of Broilers.","authors":"Yaowen Li,&nbsp;Shuang Xing,&nbsp;Xuejie Wang,&nbsp;Xiumei Li,&nbsp;Minhong Zhang,&nbsp;Jinghai Feng","doi":"10.2141/jpsa.0210089","DOIUrl":"https://doi.org/10.2141/jpsa.0210089","url":null,"abstract":"<p><p>This study was conducted to investigate the effects of increasing stocking density under suitable environmental conditions on the performance and ileal microbiota of broilers. A total of 108 Arbor Acres male broilers (28 days old) were allocated to a normal stocking density (NSD, normal stocking density; 31 kg/m²) and a maximum allowed stocking density group (MSD, maximum stocking density; 39 kg/m²). All birds were reared at a constant temperature of 21°C. At 42 days of age, bacterial DNA was extracted from ileal content, and the V3-4 hypervariable region of 16S rRNA was amplified. Increasing stocking density had no significant effect on average daily gain, average daily feed intake, and feed conversion ratio (<i>P</i>>0.05). The alpha and beta diversities of the ileal microbiomes did not differ significantly between the NSD and MSD groups; however, increasing stocking density altered the composition of ileal microbiota. The relative abundance of Lactobacillales, including <i>Lactobacillus, Enterococcus</i>, and <i>Streptococcus</i>, significantly decreased in MSD broilers, compared with NSD broilers. The present results suggest that even under suitable environmental conditions, an increase in stocking density to a level of 39 kg/m² may disturb the composition of ileal microbiota in broilers. Further studies are needed to determine the reasons and the potential consequences for animal health and physiology.</p>","PeriodicalId":16883,"journal":{"name":"Journal of Poultry Science","volume":"59 3","pages":"291-296"},"PeriodicalIF":1.5,"publicationDate":"2022-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/ee/26/jpsa-59-291.PMC9346595.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40413595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Probiotics-induced Changes in Intestinal Structure and Gut Microbiota Are Associated with Reduced Rate of Pimpled Eggs in the Late Laying Period of Hens.","authors":"Mawahib K Khogali,&nbsp;Kang Wen,&nbsp;Diego Jauregui,&nbsp;Huwaida E E Malik,&nbsp;Long Liu,&nbsp;Minmeng Zhao,&nbsp;Daoqing Gong,&nbsp;Tuoyu Geng","doi":"10.2141/jpsa.0210061","DOIUrl":"https://doi.org/10.2141/jpsa.0210061","url":null,"abstract":"<p><p>Production of pimpled or sandpaper-shelled eggs (SE) is a major problem in aged hens. Probiotics can improve eggshell quality; however, the relationship between SE production and gut bacteria remains unclear. Here, 1200 450-d-old Hy-line hens were assigned to four groups (300 hens each), with the control group fed basal diet and treatment groups fed basal diet plus 500, 1000, and 1500 mg/kg of <i>Clostridium butyricum</i> and <i>Bacillus subtilis</i>, respectively. After 4 weeks, probiotics significantly decreased the SE rate from 42.51% to 28.02%. To address why probiotics reduced SE rate, the hens that only produced normal eggs (NE) or SE based on a 2-week assessment were assigned to three groups (NE, SE, and SEP groups; 10 hens each), with the NE and SE groups fed a basal diet and SEP group fed a basal diet plus 1000 mg/kg probiotics. After 4 weeks, ileal tissues from eight birds/group were collected for histomorphological and gene expression analyses, and the ileal content was collected from five birds/group for 16S rDNA sequencing analysis. The data showed that probiotics significantly increased the villus length and ratio of villus length to crypt depth. Quantitative PCR analysis indicated that there were no significant differences in the expression of genes related to tight junctions, nutrient transport, and calcium absorption among the groups (except <i>TRPV6, P</i><0.001). The 16S rDNA sequencing analysis indicated that the alpha-diversity of gut bacteria in the SEP group was the highest among the groups. The Firmicutes phylum was dominant in the NE and SEP groups, whereas the Proteobacteria phylum was dominant in the SE group. Together, these results suggest that probiotics can significantly influence the intestinal structure and composition of the intestinal microbiota, which may lead to a reduction in the SE rate in aged hens.</p>","PeriodicalId":16883,"journal":{"name":"Journal of Poultry Science","volume":"59 3","pages":"206-222"},"PeriodicalIF":1.5,"publicationDate":"2022-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/1a/63/jpsa-59-206.PMC9346597.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40643358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Utilization of Sake lees as Broiler Feedstuff and its Effects on Growth Performance and Intestinal Immunity.","authors":"Ken R Ito,&nbsp;Tomonori Sato,&nbsp;Hiro Goto,&nbsp;Katsuyoshi Sato,&nbsp;Jun Watanabe,&nbsp;Masaki Yokoo","doi":"10.2141/jpsa.0210087","DOIUrl":"https://doi.org/10.2141/jpsa.0210087","url":null,"abstract":"<p><p>Increasing food loss and waste (FLW) is a global problem, and efforts are being made to use waste food as potential livestock feed material. The amount of self-supplied feed is lower in Japan than in other countries, and the government recommends FLW use for animal feed. Sake (Japanese rice wine) is a traditional alcoholic beverage. During the sake manufacturing process, large amounts of squeezed solids or \"lees\" (sake lees) are generated. Sake lees are nutritious and functional, but are prone to spoilage. In this study, we investigated whether sake lees should be mixed with animal feed immediately or after drying. To assess the usefulness of sake lees as a poultry feed ingredient and determine the effect of sake lees on intestinal immunity, we performed a feeding trial with three treatments: a raw sake lees (RSL) diet, dried sake lees (DSL) diet, and control diet. Three-week-old broilers were fed these diets (<i>n</i>=8 per group) for two weeks. We then calculated feed efficiency and performed RT-qPCR to assess the effects of diet on intestinal immunity. The growth performance in the RSL diet group was equivalent to that in the control diet group. The DSL diet became difficult for broilers to eat, resulting in decreased growth performance. In the ileum of RSL-diet broilers, the mRNA expression levels of TGF-<i>β</i>1 and avian <i>β</i>-defensin (AvBD)12 were significantly increased compared to those of control diet broilers (<i>p</i><0.05), and a significant correlation was observed between the two genes (<i>p</i><0.05). Our results indicated that sake lees should not be dried and should be mixed immediately with feed, and this sake lees when fed to chicken activates the intestinal immunity. However, sake lees have a lower fat content than corn, and it is thus important to combine sake lees with high-energy feed.</p>","PeriodicalId":16883,"journal":{"name":"Journal of Poultry Science","volume":"59 3","pages":"247-259"},"PeriodicalIF":1.5,"publicationDate":"2022-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/ae/81/jpsa-59-247.PMC9346602.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40643356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationship between the Lactic Acid Content and Sour Taste of Broiler Broth and the Broth of <i>Choshu-Kurokashiwa</i>-a Japanese <i>Jidori</i> Chicken.","authors":"Shohei Murata","doi":"10.2141/jpsa.0210131","DOIUrl":"https://doi.org/10.2141/jpsa.0210131","url":null,"abstract":"<p><p>The present study aimed to determine whether lactic acid content is associated with the intensity of the sour taste of <i>Choshu-Kurokashiwa</i> broth. Chicken broth was prepared using breast (<i>pectoralis major</i>) and leg (thigh + drumstick) meat of male and female <i>Choshu-Kurokashiwa</i> and broilers. These broths were assessed by a screened and trained panel and analyzed for sour taste substances (lactic, citric, pyruvic, malic, succinic, acetic, phosphoric, aspartic, and glutamic acids) and pH. The sensory sour taste was significantly higher in the <i>Choshu-Kurokashiwa</i> breast broth than in the broiler breast broth (<i>P</i>>0.001), and no significant difference was observed in the leg broths among the breeds (<i>P</i><0.05). <i>Choshu-Kurokashiwa</i> breast broth had a significantly higher lactic acid content than broiler breast broth (<i>P</i><0.001). The leg meat broth of male <i>Choshu-Kurokashiwa</i> had a significantly lower lactic acid content than that of female <i>Choshu-Kurokashiwa</i> and broiler leg meat (<i>P</i><0.01). The sensory sour taste score was significantly and positively correlated with lactic acid content in the breast broth (<i>P</i><0.001), but not in the leg broth (<i>P</i><0.1). No other organic acids were detected. Phosphoric acid and glutamic acid contents were higher in broiler broth than in <i>Choshu-Kurokashiwa</i> broth for both breast and leg meat (<i>P</i><0.001). In the breast broth, the aspartic acid content was not significantly different (<i>P</i>>0.1), and in the leg broth, it was higher in broiler and female <i>Choshu-Kurokashiwa</i> broth than in male <i>Choshu-Kurokashiwa</i> broth (<i>P</i><0.001). The present study suggests that high lactic acid content contributes to the sour taste of the <i>Choshu-Kurokashiwa</i> breast broth and demonstrated that the lactic acid content is an essential indicator for determining the sour taste of <i>Choshu-Kurokashiwa</i> breast meat.</p>","PeriodicalId":16883,"journal":{"name":"Journal of Poultry Science","volume":"59 3","pages":"297-304"},"PeriodicalIF":1.5,"publicationDate":"2022-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/cb/8a/jpsa-59-297.PMC9346599.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40413592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metabolizable and Net Energy Values of Expanded Cottonseed Meal for Laying Hens and Broiler Chickens","authors":"Yongfa Liu, Z. Ban, Peng Li, Xiaogang Yan, Lijia Li, Dan Liu, Lei Yan, Yuming Guo","doi":"10.2141/jpsa.0210033","DOIUrl":"https://doi.org/10.2141/jpsa.0210033","url":null,"abstract":"Three experiments were conducted to determine the metabolizable energy (ME) and net energy (NE) values of expanded cottonseed meal (ECSM) for broilers aged 14–16 days (Experiment 1), broilers aged 28–30 days (Experiment 2), and 45-week-old Hy-Line Brown hens (Experiment 3). Reference diets based on corn-soybean meal were used to meet the nutritional needs of the birds. The test diets contained ECSM as basis, which was used to replace 18.5% of the gross energy-yielding ingredients from the reference diet. The birds were fed a commercial feed before the experimental period. After the dietary adaptation period, six birds per replicate (Experiment 1) and two birds per replicate (Experiments 2 and 3) for each treatment group were placed in an individual open-circuit respiratory calorimetry chamber for 3 days. Daily O2 consumption and CO2 production were recorded, and excreta samples were collected. The ME and NE values of ECSM were determined using the substitution method. The apparent metabolizable energy (AME) values of ECSM for experiments 1, 2, and 3 were 2605.85, 2178.31, and 2782.60 kcal/kg of dry matter (DM), respectively. The NE values were 1655.23, 1196.64, and 1538.19 kcal/kg of DM, respectively. The NE:AME ratios of ECSM were 63.52%, 54.93%, and 55.29%, respectively. Our data showed that the ME and NE values of ECSM differed across various growth stages and types of chickens. These results demonstrate that the appropriate ME and NE should be used in the design of different feed formulas for specific growth stages and types of chickens.","PeriodicalId":16883,"journal":{"name":"Journal of Poultry Science","volume":"59 1","pages":"143 - 151"},"PeriodicalIF":1.5,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46123554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Membrane-Mediated Regulation of Sperm Fertilization Potential in Poultry","authors":"A. Asano, Chathura Priyadarshana","doi":"10.2141/jpsa.0210104","DOIUrl":"https://doi.org/10.2141/jpsa.0210104","url":null,"abstract":"Fertilization requires successful completion of molecular events taking place at different spatiotemporal scales. Transcriptionally and translationally inactive sperm need to rely on pre-assembled pathways modulated by extracellular signals that traverse the plasma membranes. However, species differences in how sperm respond to them delay the progress toward a comprehensive understanding of how activation of the signaling cascades is coordinated in poultry sperm. In chickens, recent studies have found that membrane rafts are present on the sperm surface and play important roles in regulating multistage fertilization. In this review, we focus on three steps in which membrane alteration plays a key role. The first is post-testicular maturation, in which bird sperm acquire fertilization functions through biochemical changes. The second part of this review concerns membrane regulation of sperm-egg binding and the acrosome reaction. Finally, we extend our discussion to the translation of membrane raft theory into a technical principle for the commercial production and genetic preservation of poultry.","PeriodicalId":16883,"journal":{"name":"Journal of Poultry Science","volume":"59 1","pages":"114 - 120"},"PeriodicalIF":1.5,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41320531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparation of Anti-Rabies Virus N Protein IgYs by DNA Immunization of Hens Using Different Types of Adjuvants","authors":"Nanase Kubo, M. Nishii, S. Inoue, Akira Noguchi, H. Hatta","doi":"10.2141/jpsa.0210053","DOIUrl":"https://doi.org/10.2141/jpsa.0210053","url":null,"abstract":"DNA immunization has been used to study vaccination methods and for production of specific antibodies. The present study aimed to apply DNA immunization to prepare specific IgYs, which react against rabies virus N protein (RV-N) and can be used to research and diagnose rabies virus. The DNA sequence of RV-N was ligated into a pcDNA 3.1 plasmid for constructing pcDNA-N. Eight hens were divided into four groups. Group 1 comprised the control group (non-immunized). In Groups 2, 3, and 4, hens were injected intramuscularly with pcDNA-N (400 µg/hen). Eight injections were administered every other week. From the 4th week, an adjuvant was injected in addition to pcDNA-N. Freund's complete adjuvant (FCA) and λ-carrageenan were administered to Groups 3 and 4, respectively. Eggs were collected daily, and the specific antibody activities of egg yolks were measured by ELISA. IgYs were purified from pooled egg yolks at 16–19 weeks post-administration in each group. The detection sensitivities of the RV-N were compared using purified IgY as the primary antibody for ELISA, dot blotting, and western blotting. Egg yolks from one of the two hens in Group 2 (pcDNA-N alone) and all hens in Groups 3 (pcDNA-N + FCA) and 4 (pcDNA-N + λCarra) had increased ELISA values. The combined use of λ-carrageen in DNA immunization resulted in an adjuvant effect comparable to that of FCA. Each purified specific IgY detected RV-N in the ELISA, western blotting, and dot blotting; however, the detection sensitivity differed. Higher detection sensitivity of the +λCarra IgY was observed by ELISA, whereas there was higher detection sensitivity of +FCA IgY in western blotting and dot blotting. In summary, anti-rabies virus N protein IgY was prepared through DNA immunization of hens using FCA or λ-carrageenan as adjuvants and can be used as a primary antibody to detect rabies viruses.","PeriodicalId":16883,"journal":{"name":"Journal of Poultry Science","volume":"59 1","pages":"191 - 196"},"PeriodicalIF":1.5,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42267063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Dietary Carotenoid on Egg Yolk Color and Singlet Oxygen Quenching Activity of Laying Hens","authors":"S. Kojima, Sakura Koizumi, Yukari Kawami, Yuna Shigeta, Aya Osawa","doi":"10.2141/jpsa.0210032","DOIUrl":"https://doi.org/10.2141/jpsa.0210032","url":null,"abstract":"The effects of dietary carotenoids on egg yolk were investigated in this study. Forty Rhode Island Red (RR) and 40 Silky Fowl (SF) hens that were 60 weeks old were used. Hens of each breed were randomly divided into four dietary groups. One group was fed a basal diet (crude protein 17%, metabolizable energy 2800 kcal/kg) only, whereas the other groups received a specific additive, namely, paprika extract, marigold petal extract, or Paracoccus cell powder, in addition to the same basal diet. The color and carotenoid content of egg yolk and singlet oxygen quenching activity were measured after 4 weeks. The total carotenoid content, zeaxanthin content, and singlet oxygen quenching activity in the yolk differed significantly between breeds and between diets (two-way ANOVA). The lutein content in egg yolk was affected by breed and diet, as well as by the interaction between these two factors. Regarding the Roche Yolk Color Fan values, only the effect of diet was significant. In terms of objective egg yolk color, there was a significant difference in lightness and yellowness between breeds. The total carotenoid content was higher in SF than in RR in all the groups. Likewise, the levels of zeaxanthin and lutein in the yolk were higher in SF than in RR (P<0.05). The results of the present study suggest that dietary carotenoids are effective feed additives for laying hens, especially SF, to improve the color and singlet oxygen quenching activity of egg yolk.","PeriodicalId":16883,"journal":{"name":"Journal of Poultry Science","volume":"59 1","pages":"137 - 142"},"PeriodicalIF":1.5,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47157382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Observed Incubation Behavior on Egg Production in Laying Hens of a Commercial Chicken Breed and Detection of Single-Nucleotide Polymorphisms Associated with the Incubation Behavior","authors":"Yuichiro Yonetani, Atsushi J. Nagano, H. Ueno, T. Amano","doi":"10.2141/jpsa.0210037","DOIUrl":"https://doi.org/10.2141/jpsa.0210037","url":null,"abstract":"Upon contact with laid eggs, avians initiate incubation behavior and stop laying additional eggs. This phenomenon suggests that the productivity of laying hens in free-range facilities may decrease because of frequent contact with laid eggs. Here, we examined whether hens of a commercial breed exhibit incubation behavior in a free-range facility and whether egg productivity subsequently decreases. One-hour observations were performed twice weekly for 3 weeks, during which 9 of 129 hens (7.0%) exhibited incubation behavior (i.e., sitting on eggs) in the free-range facility and were defined as incubating hens. During 4 d of continuous behavioral observation, incubating and non-incubating hens laid the same number of eggs statistically (4.6 and 3.6, on average, respectively); however, incubating hens spent significantly more time on average incubating the eggs (2071.9 min) than did the non-incubating hens (20.9 min; P<0.05), indicating a clear behavioral difference. Subsequently, the incubation behavior and egg productivity of incubating hens and a Silkie Fowl breed hen, which is known to exhibit typical incubation behavior and cessation of laying, were continuously compared for 27 d. The average minutes spent incubating eggs during the observation period increased in both the incubating hens and Silkie Fowl hen and the total time was almost the same (18,088.5 and 23,092 min, respectively). However, the Silkie Fowl hen stopped laying on day 17 after laying 17 eggs, whereas the incubating hens continued laying throughout the observation period. Incubating hens laid an average of 24.5 eggs, indicating that some hens (at least those of the commercial breed used in our study) can continue laying while exhibiting incubation behavior. A single-nucleotide polymorphism associated with incubation behavior was detected on chromosome 4 through genome-wide association analysis.","PeriodicalId":16883,"journal":{"name":"Journal of Poultry Science","volume":"59 1","pages":"121 - 128"},"PeriodicalIF":1.5,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41556956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}