British Poultry Science

Rørvang, M. V.; Hinrichsen, L. K.; Riber, A. B.

doi: 10.1080/00071668.2018.1533632pmid: 30295510

1. An on-farm assessment of keel bone, feet, plumage and skin damage was conducted in layers in small furnished cages to evaluate welfare implications.2. Thirteen farms participated, all housing Lohmann LSL layers in systems allowing 8 or 10 hens per cage.3. Each flock was visited at three different ages: 32, 62 and 77 weeks. During each visit, 100 hens were examined for keel bone fractures and deviations, plumage damage, body wounds, foot pad lesions, bumble feet, missing toes and toe wounds.4. A deterioration with age of the condition of the plumage and keel bone was found (P < 0.001). At 77 weeks of age, 16% of the birds had poor plumage, and 43% of the birds had keel bone damage. In contrast, foot pad lesions were most prevalent at 32 weeks of age (13%), whereas the other foot injuries and body wounds remained at a relatively low level throughout the three ages examined.5. Prevention of damage to the keel bone, plumage and foot pads should therefore be considered when aiming to improve welfare of laying hens housed in small furnished cages.

Yu, S.; Wang, G.; Liao, J.; Tang, M.

doi: 10.1080/00071668.2018.1533633pmid: 30293452

1. The TYR gene encodes tyrosinase, a multifunctional enzyme that is essential for melanin biosynthesis in melanocytes. This experiment involved the cloning and characterisation of the TYR gene in chicken. Five alternative splice variants were identified in the black feather bulb and designated as TYR-AS1, TYR-AS2, TYR-AS3, TYR-AS4 and TYR-AS5.2. Among the 11 chicken tissues examined, the feather bulb, comb and skin showed higher levels of all TYR variants. All TYR variants were expressed at significantly different levels in black and white feather bulbs (P < 0.05) and may be involved in melanin formation in plumage. Only TYR-AS1, which plays an important role in muscle melanogenesis, was significantly differentially expressed between black and white muscle (P < 0.01). All TYR variants were expressed at significantly different levels in black and white skin (P < 0.01).3. The mRNA expression levels of the 5 variants were closely associated with skin melanogenesis in the chicken. These findings provide new clues to the molecular mechanism of melanin formation in the Muchuan black-boned chicken.

Yuan, H.; Zhang, X.; Zhang, Q.; Wang, Y.; Wang, S.; Li, Y.; Zhang, Y.; Jing, J.; Qiu, J.; Wang, Z.; Leng, L.

doi: 10.1080/00071668.2018.1544414pmid: 30421986

1. During the long history of chicken domestication, eyelid colour, like skin colour and shank colour, has been one of the physical traits of Chinese indigenous chickens that influence consumer buying behaviour. In China, the Lindian chicken, which has coloured feathers, is renowned for the appetizing flavour of its meat and eggs, and its eyelid colours vary from deep (black) to light shades (light yellow).2. To investigate genes involved in eyelid colour, the expression profiles of black and light-yellow eyelids of Lindian chickens were analysed with transcriptome sequencing.3. A total of 13 466 genes were detected in the eyelids, among which 14 were differentially expressed. Among these differentially expressed genes (DEGs), three key genes, premelanosome protein (PMEL), dopachrome tautomerase (DCT), and tyrosinase (TYR), encoded proteins that positively regulate melanogenesis and melanin deposition. PMEL, DCT and TYR were expressed much more strongly in the black eyelids than in the light-yellow eyelids. A Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that tyrosine metabolism and melanogenesis genes were significantly enriched among these DEGs (corrected P < 0.05).4. In conclusion, melanin may be one of the main factors involved in Lindian chicken eyelid colour. Furthermore, these results provide a valuable resource for the future study of the physical traits of Lindian chicken.

Lee, J. H.; Park, J.-W.; Kang, K. S.; Park, T. S.

doi: 10.1080/00071668.2018.1547362pmid: 30427204

1. In the poultry industry, growth performance is important due to its effects on economic value. Much effort has been put forth to achieve introgression of specific genes and DNA markers related to muscle proliferation and differentiation in selective breeding approaches.2. This study investigated the biological functions of the gene Forkhead box O3 (FOXO3) during myogenic differentiation in chicken myoblast cells. FOXO3 was downregulated in primary chicken myoblast (pCM) cells by the piggyBac transposon-mediated microRNA (miRNA) knock-down (KD) system.3. The pCM cells that were stably integrated into the FOXO3 KD expression vector showed significant downregulation of FOXO3 protein and mRNA levels. Expression levels of paired box protein Pax7 (Pax7) and target genes such as CCAAT/enhancer binding protein beta and serum response element decreased in FOXO3 KD pCM cells. In addition, in the undifferentiated myoblast stage, there were no significant differences in cell morphology; however, proliferation rate in FOXO3 KD pCM cells was significantly lower during d 4 and 5 of in vitro culture. By contrast, when myotube differentiation was induced, FOXO3 KD pCM cells exhibited rapid initiation of myotube formation, higher expression of myogenin and desmin as myogenic indicators and a further differentiated phenotype than observed in regular pCM cells.4. These results demonstrated that FOXO3 promotes cell proliferation and inhibits myotube differentiation in chicken myoblast cells. Therefore, the regulation of FOXO3 could be applied to improve muscle differentiation in commercial poultry.

Beyranvand, F.; Khalaji, S.; Zamani, A.; Manafi, M.

doi: 10.1080/00071668.2018.1535167pmid: 30309249

1. Gelatin prepared from calf bones (GCB) is a novel source of high-quality protein and phosphorus. Its inclusion in broiler chicken diets may improve bone strength, plasma and digestive alkaline phosphatase activity (ALP), phosphorus digestibility and performance of broilers. Therefore, di-calcium phosphate in a corn-soy control diet was replaced with 12, 24, and 36 g/kg of GCB in a completely randomised design with four treatments of six replicates and 10 chicks in each pen. The trial lasted from 1 to 42 d of age.2. Body weight and feed intake were measured weekly. Plasma calcium and phosphorus concentration along with plasma and digestive ALP were assayed throughout the trial. Trypsin, α-amylase, lipase and total protease activity were assayed at 14 and 28 d of age. Tibia ash, calcium and phosphorus content and breaking strength were measured at 14, 28 and 42 d of age. Phosphorus digestibility was measured at 36 d of age.3. Body weight and feed intake showed no significant differences between controls and diets containing 12 and 36 g/kg GCB. Tibia ash and tibia length were increased by supplementation of GCB (P ≤ 0.001). Tibia calcium and phosphorus content were increased by GCB inclusion at 14 d of age (P ≤ 0.001). Digestive alkaline phosphatase activity was increased and trypsin activity was reduced by inclusion of GCB (P ≤ 0.001; P ≤ 0.004). α-amylase activity decreased by inclusion of 12 and 24 g/kg GCB, whereas an increase in α-amylase activity was observed by inclusion of 36 g/kg GCB (P ≤ 0.001). Supplementation of diets with GCB increased phosphorus digestibility (P ≤ 0.01) and suppressed ileum growth during the experimental period.4. Results of the current study showed that phosphorus from gelatin can greatly improve broiler bone characteristics and phosphorus digestibility and complete elimination of inorganic phosphate sources from broiler diets is feasible with inclusion of 36 g/kg high phosphorus gelatin.

Konca, Y.; Yuksel, T.; Yalcin, H.; Beyzi, S. Buyukkilic; Kaliber, M.

doi: 10.1080/00071668.2018.1547360pmid: 30421987

1. This study was conducted to determine the effects of raw and heat-treated hempseed (HHS, Cannabis sativa L.) on performance, egg quality and antioxidant activity in laying hens.2. A total of 108 laying hens, aged 36 weeks, were divided into three treatment groups with 12 replicates and each replicate contained three laying hens. The treatments were as follows: (1) Control (no hempseed), (2) 15% raw hempseed (RHS) in diet and (3) 15% HHS in the diet. Experiments lasted for 12 weeks.3. Feed intake of the RHS group was lower than those of the control and HHS groups. Egg weight, egg mass, shell weight, shell surface area and shell thickness of the HHS group were significantly (P < 0.05) higher than that of the RHS group. Roche (DSM) colour fan values of the RHS group were higher than that of the HHS group (P < 0.01).4. Palmitic, palmitoleic and oleic acids of egg yolk were significantly (P < 0.05) decreased in the RHS and HHS groups; however, linoleic, α-linolenic and docosahexaenoic acids (DHA) of egg yolk increased (P < 0.05) for both treatment diets compared to the control group.5. Both RHS and HHS supplementation to layer diets did not influence malondialdehyde (MDA) and superoxide dismutase (SOD) activity and blood lipid profile.6. It was concluded that HHS was superior in improving the egg quality of laying hens as compared to the RHS.

Niu, Y.; Zhang, J. F.; Wan, X. L.; Huang, Q.; He, J. T.; Zhang, X. H.; Zhao, L. G.; Zhang, L. L.; Wang, T.

doi: 10.1080/00071668.2018.1535166pmid: 30345798

1. A total of 648 one-day-old broiler chicks were randomly allocated into six equal groups to investigate the effect of diet supplemented with fermented Ginkgo biloba leaves (FGBL) at different levels on nutrient utilisation, intestinal digestive function and antioxidant activity.2. Broilers in the six groups were offered basal diet supplemented with either 0, 1.5, 2.5, 3.5, 4.5 and 5.5 g/kg FGBL during the 42-d experiment, respectively.3. Birds fed with 3.5 g/kg FGBL diet exhibited increased (P < 0.05) body weight gain, feed intake, apparent total tract retention (ATTR) of ether extract (EE) and relative weight of duodenum. Diets supplemented with FGBL increased (P < 0.05) antioxidant and digestive enzyme activities, and decreased malondialdehyde (MDA) concentrations at different degrees in pancreas and small intestine. The expression of antioxidant related genes was up-regulated (P < 0.05) by the transcription factor Nrf2 in small intestine, especially with supplementation of 3.5 and 4.5 g/kg FGBL in the diet. However, 5.5 g/kg diet significantly decreased (P < 0.05) feed conversion ratio and catalase activity (CAT) in the duodenum.4. Body weight, relative weight of duodenum, amylase and trypsin activities in ileum, total antioxidant capacity (T-AOC) and CAT in duodenum, and glutathione peroxidase (GSH-PX) in ileum increased linearly and quadratically with FGBL content. Activities of amylase in pancreas, trypsin in jejunum, lipase in ileum, and GSH-PX in duodenum and jejunum increased linearly with FGBL content. Body weight gain, ATTR of EE, activities of trypsin in pancreas and amylase in jejunum, total superoxide dismutase activity in duodenum, T-AOC level and concentrations of MDA in the jejunum and ileum showed a quadratic (P < 0.05) dose response as supplemental FGBL level increased.5. In conclusion, the addition of FGBL had the potential to improve nutrient utilisation, intestinal digestive function and antioxidant activity of broilers. The optimal dietary supplementation dose for broiler production seemed to be 3.5 to 4.5 g/kg.

Rama Rao, S. V.; Raju, M. V. L. N.; Paul, S. S.; Prakash, B.

doi: 10.1080/00071668.2018.1537478pmid: 30345797

1. An experiment was conducted to determine optimal non-phytate phosphorus (NPP) concentrations for White Leghorn (WL) layers (22–72 weeks) fed diet containing 38 g Ca/kg.2. Eight diets with graded concentrations (1.5–3.25 g/kg in increments of 0.25 g) of NPP were prepared. Each diet was fed to eight pen replicates containing 88 birds in each. Performance data was evaluated in three different phases (phase I-22–37 weeks, phase II-38–53 weeks and phase III-54–72 weeks). Optimum levels of NPP were determined by fitting a quadratic polynomial (QP) regression model.3. Egg production (EP) was not affected (P = 0.059) by the concentration of NPP and interaction between NPP and diet phase was non-significant, indicating that the lowest concentration (1.5 g/kg diet) of NPP used in the study was adequate across the three phases. However, EP was influenced by phase (P < 0.001).4. Optimum concentration of NPP for feed intake (FI) was estimated to be 1.5, 1.71 and 2.40 g/kg diet during phases I, II and III, respectively. FI per egg mass (EM) or feed efficiency (FE) responded quadratically with NPP and also differed significantly between phases. Optimum concentration of NPP for FE during phases I, II and III was 1.5, 2.56 and 2.32 g/kg diet, respectively.5. Egg weight (EW), EM, shell weight and thickness were not affected by NPP concentration although all of these variables (except shell weight) were influenced by phases.6. Breaking strength of tibia and Ca contents in tibia ash were not affected by the concentration of NPP, but bone ash and P contents in tibia ash were influenced (P < 0.001) by NPP. Predicted optimal concentrations of NPP for responses for tibia ash at 44 or 72 weeks, tibia ash P at 44 weeks and tibia ash P at 72 weeks were 1.55, 2.63 and 1.5 g/kg diet, respectively.7. Based on the results, it was concluded that WL layers required 1.5 g, 2.63 g and 2.4 g, respectively/kg diet during phase I, II and III with the calculated daily intake of 137.3, 278.3 and 262 mg NPP/b/d.

Tachibana, T.; Ishimaru, Y.; Takeda, K.; Khan, M. S. I.; Makino, R.; Cline, M. A.

doi: 10.1080/00071668.2018.1547361pmid: 30421962

1. The purpose of the present study was to determine if intracerebroventricular (ICV) and intraperitoneal (IP) injection of polyinosinic-polycytidylic acid (poly I:C), a viral mimetic that binds to toll-like receptor-3 (TLR3), affects food intake, voluntary activity, cloacal temperature, plasma corticosterone (CORT) and glucose concentrations, and crop emptying rate in chicks (Gallus gallus).2. Both ICV and IP injection of poly I:C significantly decreased food intake.3. IP but not ICV injection of poly I:C significantly suppressed voluntary activity, whereas ICV injection decreased time spent sitting. Both ICV and IP injection of poly I:C significantly increased plasma CORT and glucose concentration. Neither ICV nor IP injection of poly I:C significantly affected cloacal temperature.4. In addition, ICV injection of poly I:C significantly reduced crop emptying rate, whereas IP injection had no effect.5. These results suggested that central TLR3 is related to anorexia, stress response and retardation of crop emptying while peripheral TLR3 is related to anorexia, change in behaviour and stress responses during viral infection in chicks.

Yousefvand, S.; Hamidi, F.; Zendehdel, M.; Parham, A.

doi: 10.1080/00071668.2018.1547359pmid: 30444128

1. The present study was conducted to investigate whether brain somatostatin increases feed intake in neonatal chickens. The mediating role of neuropeptide Y receptors on feed intake induced by somatostatin was investigated.2. In this study, seven experiments were designed, each with four treatment groups (n = 44 in each experiment). In Experiment 1, chicks received control solution and 0.5, 1 and 2 nmol of somatostatin through intracerebroventricular (ICV) injection. In experiments 2, 3 and 4, chickens were ICV injected with control solution and 1.25, 2.5 and 5 μg of B5063 (NPY1 receptor antagonist), SF22 (NPY2 receptor antagonist) and SML0891 (NPY5 receptor antagonist), respectively. In experiment 5, 6 and 7 chickens received ICV injection of B5063, SF22, SML0891, with a co-injection of + somatostatin, control solution and somatostatin. The cumulative feed intake was measured until 120 min post injection.3. Somatostatin significantly increased feed intake in FD3 chicks. Both B5063 and SML0891 dose-dependently decreased feed intake compared with the control group, while SF22 led to a dose-dependent increase in feed intake. In addition, the hyperphagic effect of somatostatin significantly decreased with co-injection of B560 plus somatostatin (p < 0.05), but SF22 and SML0891 had no effect on feed intake induced by somatostatin in chicks (p > 0.05).4. Based on the results of this study, it is likely that somatostatin increased feed intake and NPY1 receptor acts as a mediator in hyperphagic effect of somatostatin in neonatal chicks.