British Poultry Science最新文献

1. In order to compare the difference between different derivatisations for amino acids determination of foie gras via, reversed phase high performance liquid chromatography (HPLC), O-phthalaldehyde and 9-fluorenyl-methyl chloroformate (OPA-FMOC group), phenylisothiocyanate (PITC group) and 6-Aminoquinolyl-N-hydrox-ysuccinimidyl Carbamate (AQC group) were applied to derivatisation reagent in this current experiment. The determination results of automatic amino acid analyser were applied, and 17 amino acids were detected by these three derivatisation methods.2. The running times of OPA-FMOC group, PITC group and AQC group were 18, 45 and 35 min, respectively. There was a large difference between the results of OPA-FMOC group and results from the automatic amino acid analyser, although the difference between the results from PITC and the automatic amino acid analyser was minimal.3. In conclusion, the running time of OPA-FMOC group was shorter than that of PITC group and AQC group; the accuracy of the former was better than the OPA-FMOC group and AQC group for the determination of amino acid of foie gras.

1. Infectious bursal disease (IBD) is an acute, highly contagious viral disease of chickens caused by a virus (IBDV) which has a bi-segmented, double-stranded RNA genome. It has five viral proteins in its structure; the VP1 gene is encoded in segment B and the other four are in segment A.2. In this study, bursae of Fabricius and spleen samples taken from chickens suspected of having clinical or subclinical IBD from a total of 50 chicken flocks located in different geographical regions of Turkey were examined.3. The RT-PCR analysis of the VP2 gene showed that 30 of the 50 samples (60%) tested positive. Eight positive isolates were chosen and RT-PCR was performed to amplify the VP1 gene.4. The study showed that reassortant field strains that cause clinical or subclinical disease are currently circulating in broiler flocks across Turkey.

1. This study combined genome-wide selection signal analysis with RNA-sequencing to identify candidate genes associated with high altitude adaptation and egg production performance in Nixi chickens (NXC).2. Based on the whole-genome data from 20 NXC (♂:10; ♀:10), the population selection signal was analysed by sliding window analysis. The selected genes were screened by combination with the population differentiation statistic (F_ST). The sequence diversity statistic (θπ). RNA-seq was performed on the ovarian tissues of NXC (n = 6) and Lohmann laying hens (n = 6) to analyse the differentially expressed genes (DEGs) between the two groups. The functional enrichment analysis of the selected genes and differentially expressed genes was performed.3. There were 742 genes under strong positive selection and 509 differentially expressed genes screened in NXC. Integrated analysis of the genome and transcriptome revealing 26 overlapping genes. The candidate genes for adaptation to a high-altitude environment, as well as for egg production, disease resistance, vision and pigmentation in NXC were preliminarily screened.4. The results provided theoretical guidance for further research on the genetic resource protection and utilisation of NXC.

1. The cuticle acts as a barrier to prevent microbial penetration of the eggshell. The reduction in the oviposition interval with selection for egg production and the activity of clock genes in the oviduct led to testing the hypothesis that the interval between successive oviposition of eggs would be related to the deposition of the cuticle.2. There was oviposition interval and cuticle deposition data from 2140 eggs from 5 White Leghorn pure lines for over 7 d. The association between oviposition interval and cuticle deposition was assessed using a random slopes model for each hen.3. The time of oviposition was 05:37 h:m, about 2.5 h after lights on. Differences in oviposition time between lines were significant (P=0.025). Oviposition interval was slightly greater than 24 h at 24:06 h:min with significant differences between lines (P = 0.003). The variance was low and the maximum difference between lines for oviposition interval was only 11 min. Cuticle deposition was 28.87ΔE*ab with no differences between lines.4. The number of eggs a hen laid had an effect on the oviposition interval (P = 0.004), being shortest in hens laying seven eggs (24:01 h:m) than those laying six (24:08) or five eggs (24:14).5. There was a significant positive association between cuticle deposition and oviposition interval (P = 0.007) with a minimal increase of 0.79 ΔE*ab in cuticle deposition for each additional hour of oviposition interval. Heritability for cuticle deposition in this study was 0.48 but heritability was not measurable for oviposition interval and was not different from zero for oviposition time.6. Combined with a difference between the top and tail of the distribution for cuticle deposition, there was evidence for a significant but relatively small relationship between oviposition interval and deposition of cuticle on the egg. This may have contributed to some reduction in cuticle coverage as the oviposition interval approached 24 h, but it seems unlikely that it was a major component.

1. Six pelleted diets with different ratios of whole oats to dehulled oats, ground either finely (2 mm) or coarsely (6 mm), resulting in 0.05% (LOH), 6.5% (MOH) and 11.4% (HOH) OH inclusion, were fed to broilers to study gizzard functionality and its influence on passage of large oat hull (OH) particles. The hypothesis was that coarse OH would be selectively retained in gizzard for grinding, but higher levels would increasingly result in passage of unground OH.2. In experiment 1, gizzard and small intestinal contents were sampled from 78 birds at 28-29 d of age. Neutral detergent fibre (NDF) of gizzard contents was over three times higher than that of diets, indicating selective retention. An interaction effect of OH and screen size was seen for large particles (>1.6 mm) in the upper ileum, which was higher for MOH and HOH than LOH and only for coarse diets. This indicated that passage of unground coarse large particles from the gizzard increased when it exceeded a maximum retention level.3. In experiment 2, pre-weighed amount of HOH 2 mm and HOH 6 mm diets were fed to 80 birds for 2 h and were sampled on d 30 at 0, 2, 4, 8 and16 h to study OH degradation and flow. Contents were sampled from the crop, gizzard, small intestine, colon/cloaca and excreta. Unrecovered NDF in gastrointestinal tract plus excreta increased with more time and coarseness. An interaction effect between time and screen size was found for large particles in excreta, which was higher for 6 mm diets than 2 mm diets at 16 h.4. The presence of large OH particles in excreta challenged the previous assumption that particles are ground in the gizzard to a certain critical size before passing down further down the digestive tract. Some OH seemed to escape grinding in gizzard and this was higher for coarser particles.

1. Building on established understandings regarding hormonal and metabolic-driven processes of avian embryo's growth and development, this paper proposes a novel method, focusing on sex-related dimorphism. Such processes involve crucial activities, e.g. nutrition delivery, gas exchange and waste disposal. These are influenced by interactions among various structures within embryonic compartments, whose sequential patterns between males and females have been proven different.2. The embryonic compartments, having undergone physiological changes during d 8-12, were acquired from candled images. Their temporal appearance model was developed from a non-linear classifier. It was hypothesised that if there is any distinctive pattern associated with the embryonic compartments between embryo sexes, then the classifier can be trained to recognise the dimorphism.3. The results revealed that the proposed method could separate sexes in ovo with accuracy, recall, precision and balance accuracy of 94.71, 93.47, 95.92 and 94.72%, respectively. Error analyses found 4.82% false discovery and 9.78% false omission rates. The method was expected to enhance farming resource management and leads to better animal welfare.

1. Improving resistance against disease is important in the animal and poultry industry. Besides drugs and vaccines, genetic selection for improved immune systems may be an effective approach.2. Traits related to the immune system were studied in a 938 pedigreed Japanese quail population infected by sheep red blood cells (SRBC). Besides body weight at 35 d of age (BW35), weight of the gizzard (G), liver (Li), lungs (Lu), bursa (Bu), spleen (S), heart (H), and digestive track (D) and length of ileum (I) and caecum (C) were recorded. Total antibody (TA), mercaptoethanol-resistant (IgG), mercaptoethanol-sensitive titres (IgM), the number of monocyte (M), basophil (B) and eosinophil (E) and the ratio of heterophil to lymphocyte (H/L) were measured. Co-variance components were estimated via Gibbs sampling using GIBBS3F90 software. Five univariate animal models, including simple forms, were used for genetic parameter estimations, and the best model was determined by the deviance information criterion (DIC). Genetic and environmental correlations were estimated using a bivariate animal model.3. Direct heritability estimates for internal organs ranged from 0.06 (Lu) to 0.57 (G) and for immune system traits from 0.05 (IgM) to 0.17 (IgG). Negative genetic correlations were found between BW35 and internal organs (-0.22 to -0.80).4. Including one of the internal organs, such as the spleen, in the selection index improved the immune response in heavier birds. Additionally, because of the moderate heritability of IgG (0.17) and its effect on lasting immunity, selecting for higher IgG concentration may improve the resistance of Japanese quail against pathogens.

1. Modern broiler chickens are among the most efficient livestock in terms of resource requirements and production time. To maintain and improve production efficiency and meat quality and account for welfare problems, early interventions, such as incubation temperature, require investigation2. In this study, Ross 308 broiler eggs were incubated at either 36.5°C or 38.5°C on embryonic days (ED) 4-7. The control group eggs were incubated at a constant temperature of 37.5°C. Musculus pectoralis and musculus gastrocnemius samples were taken for the investigation of muscle physiology, and the tibia was sampled for bone strength analysis from chickens aged 35 and 36 d. In addition, meat quality was analysed and gait scoring was performed.3. The performance of chickens in the 36.5°C group was inferior to those in the other groups up to d 10 post-hatch, but compensatory growth was seen by d 35 of age. Meat quality was unaffected, but significant differences between sexes were observed. Males had lighter meat colour than females. Muscle glycogen and intramuscular fat were unaffected by the incubation temperature, but the muscularis pectoralis and gastrocnemius intramuscular fat contents were greater in males than in females, accompanied by the increased expression of enzymes involved in lipolysis. In the 38.5°C group, males had less bone elasticity than females, and the inverse was observed in the other groups. Gait scores were affected by sex but not incubation temperature.4. The results of this study showed a stronger effect of sex than incubation temperature on broiler muscle physiology, bone strength, performance and meat quality.

1. This study aimed to investigate the effect of the first and third parities and one male: four females (1 M:4F) and 1 M:6F sex ratios of White Roman geese on their reproductive performance and biochemical parameters in an environmentally controlled house.2. Ganders (n = 136) and geese (n = 656) from the first and third parity were randomly placed into eight pens. These eight pens were assigned to one of four treatments in a 2 × 2 factorial arrangement (two sex ratio groups × two parity groups). The first and third parity treatment groups had 1 M:4F (each pen containing 20 ganders and 80 geese) and 1 M:6F (each pen containing 14 ganders and 84 geese) sex ratio treatment groups, respectively, replicated twice.3. Blood samples were collected from the geese at different time points: upon entering the house (ST), the beginning of the lighting regime of 7 L:17D for six weeks (LC6W), lighting adjustment to 9 L:15D for 6 weeks (9C6W), the peak of egg production (PEP) and the end of egg production (EEP).4. The first parity group had a longer laying period than the third parity (274 vs.191 days). First parity had a lower egg production rate than third parity during whole stage (18.7 vs. 25.4%). Fertility in 1 M:4F group was significantly higher than in 1 M:6F rate group (54.7 vs. 45.1%) at all periods.5. Plasma levels of total protein, albumin, globulin, triglycerides, calcium and phosphorus concentrations were significantly higher for whole laying period in first parity geese compared to third parity birds.

1. Loop-mediated isothermal amplification (LAMP) assays were developed to detect Salmonella enterica subspecies enterica serotypes Enteritidis and Heidelberg in poultry farms. These serotype-specific methods were evaluated in comparison with PCR in the analysis of different Salmonella spp. serotypes from a culture collection and poultry farm samples.2. The results demonstrated the specific amplification of the genetic targets safA in all S. Enteritidis (n = 10) and ACF69659 in all S. Heidelberg (n = 36) isolates from the culture collection. The remaining isolates from other Salmonella spp. serotypes (n = 84) and bacterial species (n = 8) were negative in both LAMP assays.3. The methods detected DNAs from S. Enteritidis and S. Heidelberg after a single-step pre-enrichment in buffered peptone water of the poultry samples, which agreed with previously developed PCR methods to detect these same two serotypes.4. In conclusion, LAMP assays were useful for rapid serotype-specific detection, being suitable for surveillance purposes in resource-limited environments such as poultry farms.