Female Chickens Research Articles

Genotype by Environment Interactions (G*E) of Chickens Tested in Ethiopia Using Body Weight as a Performance Trait.

Ethiopia is a developing nation that could highly benefit from securing food via improved smallholder poultry farming. To support farmer and breeding decisions regarding which chicken strain to use in which Ethiopian environment, G*E analyses for body weight (BW) of growing male and female chickens were conducted. Research questions were (1) if a G*E is present for BW and (2) which strain performs best in which environment in terms of predicted BW. Analyses were performed using predicted BW at four different ages (90, 120, 150, and 180 days) of five strains (Horro, Koekoek, Kuroiler, Sasso-Rhode Island Red (S-RIR), and Sasso) tested in five Ethiopian regions (Addis Ababa, Amhara, Oromia, South Region, and Tigray) that are part of three Agro-Ecological Zones (AEZ) (cool humid, cool sub-humid, and warm semi-arid). The indigenous Horro strain was used as a control group to compare four other introduced tropically adapted strains. The dataset consisted of 999 female and 989 male farm-average BW measurements. G*E was strongly present (p < 0.001) for all combinations of strain and region analyzed. In line with previous research, Sasso was shown to have the highest predicted BW, especially at an early age, followed by Kuroiler. Horro had the lowest predicted BW at most ages and in most regions, potentially due to its young breeding program. The highest predicted BW were observed in Tigray, Oromia, and Amhara regions, which are in the main part of the cool sub-humid AEZ.

Pendugaan Bobot Badan Melalui Ukuran Shank pada Ayam Kampung yang Dipelihara Secara Tradisional di Manokwari

This study aims to find an estimator of body weight by means of shank length and shank circumference in adult Kampung chickens reared traditionally. A total of 173 adult Kampung chickens (79 males and 94 females), aged 1 year belonging to several breeders in Prafi District, Manokwari Regency, were used as material for this study. Best Subsets Regression analysis was used to find the best body weight estimation model for this research chicken. The results showed that shank length (PSJ) was the best estimator of body weight (BBJ) for adult male Kampung chickens through the formula: BBJ = 0.363 PSJ – 1.67, because it had the best accuracy rate (highest R2 and lowest C-p and s) compared to the formula others available. For adult female Kampung chickens, shank length (PSB) and shank circumference (LSB) are the best estimators of body weight (BBB) for adult female Kampung chickens using the formula: BBB = 0.205 PSB + 0.127 LSB - 0.864, because it has the best level of accuracy (R2 highest and C-p and lowest s) compared to other available formulas. These formulas are very well applied to Kampung chicken farms that are kept traditionally in an area in order to choose good male candidates and prospective brooders for that area.

Characterization of Myostatin (MSTN) Gene Using PCR-RFLP Method in KUB Chicken

This study aims to obtain MSTN gene diversity and MSTN gene association. The materials used in this study were 96 KUB chickens and 96 KUB chicken blood samples consisting of 41 males and 55 females. This research method is an experiment. Data collected included body weight, weight gain and body size of male and female KUB chickens, and diversity and association of MSTN genes. Data analysis used mean difference test (T-test), T2-Hotelling, Principal Component Analysis (PCA), Genotype and allele frequencies, Hardy-Weinberg equilibrium, Heterozygosity and Polymorphic Information Content (PIC). The results showed that body weight at 1 and 2 months of age, body weight gain at 1-2 months and body size of male KUB chickens at two months were significantly (P&lt;0.05) higher than female KUB chickens. The body size characteristic of male and female KUB chickens is chest circumference (CC) while the body shape characteristic is wing length (WL). The MSTN|MspI gene in KUB chickens is polymorphic. The KUB chicken population is in Hardy-Weinberg imbalance. Heterozygosity of the KUB chicken population showed a value of Ho (0.31) &lt; He (0.51). The MSTN| MspI gene of KUB chicken was associated with body weight, weight gain and body measurements and the best genotype was (-/-).

A Review on Production, Reproduction, Morphometric, and Morphological Characteristics of Ethiopian Native Chickens

Native chickens in Ethiopia are characterized in a fragmented manner for their performance characteristics and genotypes. This review aimed to explore the production and reproduction performance characteristics as well as the morphometric and morphological diversity of Ethiopian native chickens. The investigation was performed on four production performance characteristics, including average egg per clutch, average clutch/hen/year, average egg set/hen, and average egg/hen/year, as well as six reproductive performance characteristics, including age at first laying, age of male chickens at first bred, age at which female chickens are first bred, the reproductive life span of males and females, and fertility percentage in various parts of Ethiopia. Some economically practical morphometric characteristics of native chickens, such as shank length, chest circumference, comb length, body weight, body length, keel length, wattle length, neck length, back length, and morphological diversity, were also summarized. Regarding performance characteristics, there were some variations in eggs’ average production performance per clutch (13.56-15.4 eggs) and clutch/hen/year (3.0-4.29) in Ethiopia. The average reproduction performance characteristics of Ethiopian native chickens for age at first laying (6.90-7.13 months), age of male chickens at first bred (5.87-6.15 months), female at first bred (5.20-5.93 months), the reproductive life span of males (3.79 years) and hens (3.56 years), and chicks hatched from set eggs revealed variation across Ethiopia. In various locations of Ethiopia, the average trait values reported for Ethiopian native chickens under the farmer’s management differed in terms of morphometric and morphological features. The variation observed in performance characteristics, as well as morphometrics and morphological characteristics for Ethiopian native chicken ecotype population, can help the native breed classification, unique trait conservation, and breed improvement intervention programs.

Effect of carnosine synthesis precursors in the diet on jejunal metabolomic profiling and biochemical compounds in slow-growing Korat chicken

The slow-growing Korat chicken (KR) has been developed to provide an alternative breed for smallholder farmers in Thailand. Carnosine enrichment in the meat can distinguish KR from other chicken breeds. Therefore, our aim was to investigate the effect of enriched carnosine synthesis, obtained by the β-alanine and L-histidine precursor supplementation in the diet, on changes to metabolomic profiles and biochemical compounds in slow-growing KR jejunum tissue. Four hundred 21-day-old female KR chickens were divided into 4 experimental groups: a group with a basal diet, a group with a basal diet supplemented with 1.0% β-alanine, 0.5% L-histidine, and a mix of 1.0% β-alanine and 0.5% L-histidine. The feeding trial lasted 70 d. Ten randomly selected chickens from each group were slaughtered. Metabolic profiles were analyzed using proton nuclear magnetic resonance spectroscopy. In total, 28 metabolites were identified. Significant changes in the concentrations of these metabolites were detected between the groups. Partial least squares discriminant analysis was used to distinguish the metabolites between the experimental groups. Based on the discovered metabolites, 34 potential metabolic pathways showed differentiation between groups, and 8 pathways (with impact values higher than 0.05, P < 0.05, and FDR < 0.05) were affected by metabolite content. In addition, biochemical changes were monitored using synchrotron radiation-based Fourier transform infrared microspectroscopy. Supplementation of β-alanine alone in the diet increased the β-sheets and decreased the α-helix content in the amide I region, and supplementation of L-histidine alone in the diet also increased the β-sheets. Furthermore, the relationship between metabolite contents and biochemical compounds were confirmed using principal component analysis (PCA). Results from the PCA indicated that β-alanine and L-histidine precursor group was highly positively correlated with amide I, amide II, creatine, tyrosine, valine, isoleucine, and aspartate. These findings can help to understand the relationships and patterns between the spectral and metabolic processes related to carnosine synthesis.

Growth Performance of Native Hen at the Grower Phase (Aged 6-12 weeks) After Supplemented Arginine-Lysine in Low-Protein Fed

This study aims to determine the growth performance of female Native chickens at the grower phase (6-12 Weeks) after being given arginine-lysine in low protein feed. This research was carried out from May to August 2022 at the Kampung Chicken Housing, Sion Women's Farmer Group, Sasi Village, Kefamenanu. The material used is 80 Native chickens aged 6-12 weeks with an average body weight of 400 g. The research method used is a complete randomized design. Chickens were randomly placed for 5 treatments and 4 replications, each replication consisted of 4 bird. The treatment given was P0 (control feed + 0.60% arginine + 0.52% lysine + 18% CP); P1 (control feed + 0.70% arginine + 0.61% lysine + 17% CP); P2 (control feed + 0.80% arginine + 0.70% lysine + 16% CP); P3 (control feed + 0.90% arginine + 0.79% lysine +15% CP); P4 (control feed + 1.00% arginine + 0.88% lysine + 14% CP). Variables observed were body weight gain, feed intake and feed conversion ratio. Data analysis using variance analysis and Duncan test. The results showed that the average body weight gain at treatments P0, P1, P2, P3 and P4 were 71.67±3.75; 84.69±3.55; 105.63±3.71; 105.46±7.15; and 94.38±3.50 g/bird/week, respectively. Feed intake were 277.41±15.95; 324.98±13.20; 401.13±15.10; 397.19±30.00; and 363.30±12.06 g/bird/week. Feed conversion ratio were 3.87±0.02; 3.84±0.01; 3.80±0.02; 3.77±0.03; and 3.85±0.01. Analysis of variance showed that the treatment had a significant effect on body weight gain, feed intake and feed conversion ratio of female Native chickens at the grower phase (P&lt;0.05). It was concluded that the use of the arginine-lysine increases body weight gain, feed intake and decreases feed conversion ratio of female Native chickens at the grower phase (6 – 12 weeks). The level of 0.80-0.90% arginine + 0.70-0.79% lysine can streamline the use of feed crude protein by 2-3% from 18% to 15-16% and provide maximum results on the performance of female Native chickens at the grower phase.

Ascaridia galli infection in chicken: Pathobiology and immunological orchestra.

Ascaridia galli is the largest gut-dwelling helminth of chickens, which confers adverse effects on meat and egg production; thus, on the animal protein supply and the economy. Both adult and immature parasites affect gut health, but larval stages play a major role in pathology. Here, we present immunology and pathology of A. galli in chickens. Literatures were surveyed through online platforms such as PubMed, Google Scholar and Researchgate. The larvae cause excessive mucus production, damage to the intestinal gland, hemorrhage, anemia, diarrhea, and malnutrition. The adult worms can cause death by intestinal obstruction and intussusception. Although both cellular and humoral immunity are involved in fighting against ascariasis, the role of naturally acquired immunity is poorly defined. In cellular immunity, Th-2 cytokines (IL-4, IL-5, IL-9, and IL-13), goblet cells (mucin), gut-associated lymphoid tissues, CD8α+ intraepithelial cells, TCRγδ + T cells, and TGF-β4 form a protective band. Type 2 immunity provides protection by forming a network of endogenous damage-associated molecular patterns, chitin, and parasitic antigens. Among antibodies, IgY is the most prominent in chickens and provides temporary humoral protection. During parasitic infection, infiltration of various immune cells is evident, especially in the intestinal epithelium, lamina propria, and crypts of the duodenum and jejunum. In chickens older than 12 weeks, gradual reduction of worm burden is more successful than the younger birds. Female chickens exert a short-lived but higher level of protection by passing IgY to chicks in the form of egg yolk antibodies. In laying conditions, immunity differs between breeds. This review provides an overview of the silent but inevitable pathological changes induced by A. galli and the interaction of host immunity with the parasite.

Metabolic rate does not explain performance on a short-term memory task or personality traits in juvenile chickens (Gallus gallus domesticus).

Metabolic rate determines life processes and the physiological requirements of an individual, and has recently been implicated as a driver of inter-individual variation in behaviour, with positive correlations associated with boldness, exploration and aggressive behaviours being recorded. While the link between metabolism and personality has been explored, little is known about the influence of metabolism on cognitive abilities. Here we used juvenile female chickens (Gallus gallus domesticus) to investigate the relationships between metabolic rate at rest, short-term memory, personality, and dominance. Resting metabolic rates of the chicks were measured over a three-week period, concurrently with measures of short-term memory using an analogue of the radial arm maze. We also measured latency to leave the shelter (boldness), neophobia (fear of novel objects) and dominance within a group, both before and after short-term memory trials. We found that metabolic rate did not explain inter-individual differences in short-term memory, personality traits or dominance, suggesting that energy allocated to these traits is independent of individual metabolic rate, and providing evidence for the independent energy-management hypothesis. Differences in short-term memory were also not explained by boldness or neophobia. Variation in behaviour in chicks, therefore, appears to be driven by separate, currently unknown variables.

Association of Growth Hormone Gen with KUB Chicken Productivity

This study aims to investigate the diversity of quantitative characteristics and GH genes, along with the association between GH genes and quantitative characteristics. The research material consisted of 96 KUB chickens aged DOC-2 months and corresponding blood samples. The t-test was utilized to determine differences in body weight, weight gain, and body measurements between male and female KUB chickens, and assess the diversity of the GH gene. T2-Hotelling analysis was employed to compare body measurements between male and female KUB chickens, while principal component analysis was used to identify size and shape characteristics. Male KUB chickens' average body weight, weight gain and body size were significantly (p&lt;0.05) higher than females. The analysis of the growth hormone gene exhibited three genotypes: +/+ (0.51), +/- (0.35), and -/- (0.14). Additionally, two alleles were identified: (+) accounting for 0.68% and (-) accounting for 0.32%. The growth hormone gene MspI of KUB chickens demonstrated polymorphism, with X2 count (2.93) &lt; X2 table 0.05 (3.84). The heterozygosity value in the KUB chicken population was 0.43, and the obtained PIC value was 0.38. The genotype +/+ of the growth hormone gene in KUB chickens was significantly higher (p&lt;0.05) than genotypes +/- and -/-.In conclusion, male KUB chickens exhibited higher body weight, weight gain, and body measurements compared to female KUB chickens. The chest circumference served as the identifier for body size in both male and female KUB chickens, while the length of the upper body and tibia length distinguished the shape characteristics of male and female KUB chickens, respectively. KUB chickens' growth hormone gene MspI was associated with body weight, weight gain, and body measurements, with the (+/+) genotype being the most favorable

Breed characterization of native chickens based on their head shape and size

Native chickens have unique characteristics related to adaptation to the most diverse breeding systems. The phenotypic characterization of different chicken ecotypes is necessary in view of the current situation of loss of local genetic resources. Development of methodologies capable of supporting morphometric studies is very useful in native domestic breeds conservation. Thus, geometric morphometrics is a recently proposed approach for the quantification of shape and size variation separately, which has shown advantages over the traditional method. The objective of this study was to characterize female chickens of the Peloco, Barbuda, and Caneluda breeds based on their head shape and size by using geometric morphometric. Images of the head of 85 chickens were captured, and 13 landmark and semi-landmark were set in the beak, nostril and eye regions. The three chicken breeds evaluated showed significant differences (p &lt; 0.01) regarding the head shape. Most variations occurred in the eyes and beak; the Peloco breed presented wide and curved beak, and round eyes. According to the grouping analysis, the Peloco and Caneluda breeds had similar head shape and were allocated to the same group; and the Barbuda breed was allocated separated from the others by differing from them. The breeds presented significant differences (p &lt; 0.01) in size, and the Caneluda breed had the largest head size. The geometric morphometrics allowed the distinction of the breeds by identifying shape variations, especially in the beak and eye regions. Thus, it is promising for studies on phenotypic diversity and breed characterization of these birds.

Heat stress effects on the genetics of growth traits in Thai native chickens (Pradu Hang dum).

The objective of this study was to investigate the effect of heat stress on the growth traits and genetic parameters of Thai native chickens. A total of 16,487 records for growth traits of Thai native chickens between 2017 and 2022 were used in this study. Data included the body weight at birth, body weight at 4, 8, and 12 weeks of age (BW0, BW4, BW8, BW12), average daily gain during 0 to 4, 4 to 8, and 8 to 12 weeks of age (ADG0-4, ADG4-8, ADG8-12), absolute growth rate at birth, at 4, 8, and 12 weeks of age (AGR0, AGR4, AGR8, AGR12). The repeatability test day model used the reaction-norm procedure to analyze the threshold point of heat stress, rate of decline of growth traits, and genetic parameters. At temperature and humidity index (THI) of 76, Thai native chickens began to lose their growth traits, which was the onset of heat stress in this study. The estimated heritability, genetic correlation between animal and heat stress effect, and correlations between the intercept and slope of the permanent environmental effects were 0.27, -0.85, and -0.83 for BW, 0.17, -0.81, and -0.95 for ADG, 0.25, -0.61, and -0.83 for AGR, respectively. Male chickens are more affected by heat stress than female chickens with a greater reduction of BW, ADG, and AGR, values equal to -9.30, -0.23, -15.21 (in males) and -6.04, -0.21, -10.10 (in females) gram per 1 level increase of THI from the THI of 76. The influence of thermal stress had a strong effect on the decline in growth traits and genetic parameters in Thai native chickens. This study indicated that genetic models used in conjunction with THI data are an effective method for the analysis and assessment of the effects of heat stress on the growth traits and genetics of native chickens.

Effects of the in ovo injection of an Escherichia coli vaccine on the hatchability and quality characteristics of commercial layer hatchlings

In the commercial egg industry, avian pathogenic Escherichia coli (APEC) can lead to significant economic loss. The Poulvac E. coli vaccine (PECV) is a commercially available attenuated live vaccine commonly applied via spray or drinking water to protect against losses associated with colibacillosis. The PECV has not been tested in layer hatching eggs using in ovo injection. Therefore, the purpose of this experiment was to determine the effects of injecting 50 μL of different doses of the PECV into Hy-Line W-36-layer hatching eggs on the hatchability and quality characteristics of hatchlings. At 18 d of incubation (DOI), treatments included 1 noninjected and 1 diluent-injected control. Furthermore, PECV treatments included a full dose (4.4×108E. coli CFU) or serial dilutions of the full dose to produce 4.4×106, 4.4×104, or 4.4×102 CFU doses of E. coli. In ovo injections targeted the amnion. Percent hatchability of live embryonated eggs (HI), percent residue eggs, hatchling mortality, and female chick whole and yolk-free BW, relative yolk sac weight, and body length were among the variables examined. Treatment significantly (P < 0.0001) affected HI, with HI being highest in the control groups (97.3% in the noninjected and 94.2% in the diluent-injected), and with HI values being 89.0, 88.9, 84.4, and 71.2% in the 4.4×102, 4.4×104, 4.4×106, and 4.4×108 CFU E. coli dose treatments, respectively. The percentage of live embryos that did not complete hatch but that pipped internally (P=0.024) or externally (P < 0.0001) were significantly affected by treatment, with percentages being highest in the 4.4×108 CFU treatment. Female chick body length was significantly (P < 0.0001) affected by treatment and was longer in both control groups and in the 1×102 CFU E. coli treatment in comparison to all other treatments. Yolk-free female chick BW was significantly (P=0.034) affected by treatment and was lower in the 4.4×106 CFU and 4.4×108 CFU treatments when compared to the diluent-injected control group. An increase in the E. coli concentration administered in the amnion of embryonated layer hatching eggs at 18 DOI decreased hatch success and female chick yolk-free BW and body length.

Influence of palm kernel cake on the growth performance, gut health and hematochemical indices of slow-growing broilers

ABSTRACT Four hundred and fifty (450) 3-week-old male and female broiler chicks were randomly allocated to a control diet and four dietary treatments with six replicates in a completely randomized design (CRD) with 15 birds per replicate arranged in a 2 × 2 factorial design to evaluate the effect of palm kernel cake (PKC) diet and multi-blend enzymes on the performance of Sasso broilers. The five dietary treatments were T0 = (control, standard diet), T1 = PKC1*0% (10% PKC with no enzyme), T2 = PKC1*0.05% (10% PKC with enzyme), T3 = PKC2*0% (20% PKC with no enzyme) and T4 = PKC2*0.05% (20% PKC with enzyme). The interactive effect of PKC and enzyme showed improved (p < 0.05) FCR in T1 and T2. Higher counts (p < 0.05) of Lactobacillus spp. were found in PKC2 than in PKC1 and lower Clostridium perfringens counts in T3 compared to T2 at 8 weeks. At week 12, the PKC-enzyme effect resulted in higher (p < 0.05) platelets in the T2 and T4 groups than in the other treatments. The incorporation of 10% PKC with enzyme into the diets of Sasso broilers could maintain bacteria balance in their gut and enhance growth performance.

Physiological effects of PFAS exposure in seabird chicks: A multi-species study of thyroid hormone triiodothyronine, body condition and telomere length in South Western France

There is growing evidence that poly and perfluoroalkyl substances (PFAS) exposure leads to the disruption of thyroid hormones including thyroxine (T4) and triiodothyronine (T3), and may affect telomeres, repetitive nucleotide sequences which protect chromosome ends. Many seabird species are long-lived top predators thus exhibit high contaminant levels, and PFAS-disrupting effects on their physiology have been documented especially in relation to the endocrine system in adults. On the contrary, studies on the developmental period (i.e., chicks), during which exposure to environmental contaminants may have a greater impact on physiological traits, remain scarce to this date. We carried out a multi-species study with the aim to assess whether and to which extent chicks of four gull species (herring gull, great and lesser black-backed gull, yellow-legged gull) in South Western France are contaminated by PFAS, and to bring further evidence about their potential physiological consequences. Linear PFOS showed concentrations of concern as it was generally >10 times higher than the other PFAS, and exceeded a threshold toxicity level (calculated from previous studies in birds) in almost all sampled chicks. Nonetheless, in herring gull male chicks, total T3 levels were significantly and negatively associated with perfluorodecanoate (PFDA) and perfluorododecanoate (PFDoDA) and positively associated with perfluorotetradecanoate (PFTeDA) in female chicks. Total T3 levels were also positively associated with PFDoDA in great black backed gull male chicks and with perfluorotridecanoate (PFTrDA) in lesser black backed gull chicks. In lesser and great black-backed gulls, both females and males showed significant negative associations between several PFAS and their body condition, and a positive association between telomere length and L-PFOS in the yellow-legged gull was also found. These results corroborate previous findings and need to be further explored as they suggest that PFAS may interfere with the physiological status of chicks during the developmental period, potentially inducing long-lasting consequences.

Effects of traditional Chinese herbal feed supplement on growth performance, immunity, antioxidant levels, and intestinal health in chickens: a study on Ningdu yellow chickens

Traditional Chinese herbs have been widely researched as a green, safe, and effective feed additive for poultry. The purpose of this study was to investigate the effects of traditional Chinese prescription (TCP) based on various herbs in a specific ratio on the growth performance, carcass traits, immunity, antioxidant level, and intestinal health of Ningdu yellow chickens. A total of 420 female Ningdu yellow chickens were randomly divided into 5 groups, with 6 replicates of 14 each. The chickens were fed with a basal diet supplemented with 0 (CON), 0.2, 0.4, 0.6, or 0.8% TCP from d 43 to 105. Body weight, feed intake, and serum biochemical indicators were recorded at d 70 and 105, intestinal morphology and microflora of the carcass were determined at d 105. Compared to the control group, chickens fed with TCP, particularly at the level of 0.6%, showed improved average daily gain and breast muscle percentage, as well as a lower feed-to-gain ratio with statistical significance (P < 0.05). Between 43 and 70 d of age, chickens fed with TCP exhibited higher levels of serum glutathione peroxidase activity, total antioxidant capacity, and superoxide dismutase, particularly in the group fed with the 0.6% level of TCP (P < 0.05). Between 43 and 105 d of age, feeding chickens with 0.4 and 0.6% TCP resulted in a decrease in serum IL-2 concentration, and increase in the IL-4 content (P < 0.05). Chickens fed with 0.4, 0.6, and 0.8% TCP had significantly higher jejunum villous height (P < 0.05), TCP supplementation also led to a marked increase in the relative abundance of Bacteroidota compared to the control group (P < 0.05). Collectively, the study suggests that TCP supplementation can enhance immune and antioxidant functions, improve jejunum morphology, and positively impact cecum microflora in chickens. Based on these results, a level of 0.6% TCP could be considered an optimum level as a feed supplement for Ningdu yellow chickens aged 43 to 105 d.

Morphological and morphometric features of indigenous chicken in North Shewa zone, Oromia regional state, Ethiopia

This study was conducted in the Kuyu and Girar Jarso districts of north Shoa Zone Oromia regional state, Ethiopia, to generate information on the morphological and morphometric characterization of local chicken ecotypes. Multi-stage purposive random sampling technique was used to collect the data. Morph metric data were collected on body weight and other linear measurements and analyzed using the statistical analysis system’s generalized linear model (GLM) procedures. A total of 576 (192 male and 384 female) chickens were considered for qualitative and quantitative traits studies. The results showed that all indigenous chicken in the study area possesses normal feather morphology where, as 99.5% normal and 0.5% crest feather distribution were found. The dominant skin color was yellow, 59.2%, followed by white, 31.6%. With regard to shank color, the yellow color was the dominant (47.6%), followed by white (29.3%) and gray (16.7%). Red (13%), white (11.8%), and Kohima (11.1%) were the predominant plumage colors observed in the study area. The overall mean of body weight, chest circumference, wing span, body length, and shank length for males and females were 1.7 and1.2 kg, 28.7 and 27 cm, 40.4, 39.4, 37.5, 35.3, 8.4 and 8.2 cm respectively. In the present study, morphological and phenotypical variations have been observed among the indigenous chicken populations; hence, an in-depth molecular evaluation is needed to show the level of genetic variation and relationship among them.

Female-Biased Expression of R-spondin 1 in Chicken Embryonic Gonads Is Estrogen-Dependent.

The mechanism of sex determination in chickens, especially the molecular mechanism of female ovarian development, has not yet been fully elucidated. Previous studies have shown that RSPO1, which is associated with ovarian development in mammals, might have a conserved role in chickens. In this study, we systematically investigated the spatiotemporal expression pattern of RSPO1 in various tissues, especially gonads, of male and female chicken embryos using qPCR and Western blotting, and we explored its correlation with the expression of key genes in the estrogen pathway using drug treatment or gene overexpression in vivo and in vitro. Our results reveal that RSPO1 was widely expressed in all examined tissues of chicken embryos, showing a female bias in gonadal tissues at both the mRNA and protein levels. Surprisingly, RSPO1 was not differentially expressed between male and female gonadal cells with fadrozole-induced estrogen pathway blockades, and furthermore, estradiol-induced estrogen stimulation altered the expression of RSPO1. In addition, overexpression of RSPO1 in gonadal cells induced the mRNA expression of its downstream target genes, Wnt family member 4 (WNT4) and Catenin beta 1 (CTNNB1), and that of estrogen receptor α (ERα), an estrogen pathway gene. In summary, this study provided new evidence for elucidating the role of RSPO1 in ovarian development in poultry.

Effects of dietary chitosan oligosaccharides supplementation on meat quality, chemical composition and anti-oxidant capacity in frizzled chickens

The aim of this study was to evaluate dietary chitosan oligosaccharides (COS) supplementation on meat quality, chemical composition and oxidative stability in frizzled chickens. A total of 360 one-day-old female frizzled chickens with an average body weight of 34.38 ± 1.23 g were randomly allocated to four groups with six replications (10 chickens/replication) in this 84-day experiment. The chickens in the control group (CON) fed the basal diet and the other three experimental diets were based on the basal diet with 300, 600 and 900 mg/kg COS supplementation, respectively. The results indicated that dietary COS increased growth performance, eviscerated and breast muscle yield while decreased abdominal fat yield, accompanied with increasing pH45min, pH24h, Lightness, drip loss and cooking loss in breast and thigh muscle. The scavenging activity of 2,2-diphenyl-1-picrylhydrazyl, superoxide radical, hydroxyl radical and 2,2-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt, the activity of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) in breast and thigh muscle were improved by COS while malondialdehyde content was decreased. COS up-regulated the gene expression of nuclear factor erythroid 2-related factor 2, heme oxygenase-1, NAD(P)H quinone dehydrogenase 1, SOD, CAT and GSH-Px in breast and thigh muscle. In conclusion, dietary COS supplementation improved meat quality by improving pH, colour, water holding capacity and anti-oxidant capacity, accompanied with decreased lipid metabolism in frizzled chickens. Dietary 600 mg/kg COS was recommended in frizzled chickens’ diet to improve meat quality. Highlights COS improves growth performance of frizzled chickens. COS improves meat quality of frizzled chickens. COS enhances anti-oxidant capacity of frizzled chickens’ meat.

Molecular evidence for the involvement of alternative splicing in jejunum epithelial cells in broiler chickens fed dietary supplementation with olive mill wastewater.

There is no doubt that alternative splicing is conserved in chickens and mammals, but evaluating the effects of nutrition on alternative splicing in chickens is crucial in a wide range of fields. Although the olive diet has been extensively studied in human, mouse, and chicken systems, little is known about its impact on chicken alternative splicing systems. Hence, the current study aimed to assess the effect of feeding polyphenol-enriched olive mill wastewater to female broiler chickens via alternative splicing by analyzing high-throughput sequencing raw reads of RNA utilizing genomics and bioinformatics methodologies. It also aimed to look for differences in isoform expression and discover molecular functions and biological processes linked to differentially transcribed genes. The findings of our study revealed that 51 genes involved in isoform switching and alternative splicing events were not used evenly. This is due to the reduced use of ATSS in olive mill wastewater groups compared to control groups. Furthermore, the gene ontology analysis revealed that 25 GO terms were enriched in biological processes, 16 GO terms were enriched in molecular function, and 25 GO terms were enriched in cellular components. Kinase and adenylyltransferase activities were significantly enriched in terms. The molecular analysis presented herein provides valuable insight into the role of phenolics in alternative gene-splicing mechanisms in chickens, demonstrating how an industrial waste product can be repurposed as a feed supplement with a satisfactory outcome.

Morphometric Measurements of Several Body Parts of Laying Phase Arabian Chickens

The objective of this research was to investigate the body measurements of female Arabian chickens during the laying phase. The study utilized a sample of 95 female Arabian chickens, aged 94 weeks, which were housed in battery cages and utilized for egg production. Direct measurements were taken on each chicken, with variables including body weight, head circumference, beak length, comb height, neck length, back length, wing length, chest width, chest depth, upper thigh length, lower thigh length, shank length, shank circumference, the distance between the pubis bones, the distance between the pubic bone and sternum, and the length of the phalanges. The results of the study indicated that the body weight and morphometric measurements of the Arabian chickens were consistent with prior research. Furthermore, the size of the chest, back, neck, and wings displayed a significant correlation with body weight. Therefore, these measurements can be used as indicative markers for predicting the body weight of Arabian chickens.