Female Ducks Research Articles

APPLICATION OF MULTIVARIATE STATISTICAL ANALYSIS IN CHARACTERISING THE PHENOTYPIC VARIABILITY OF LOCALLY ADAPTED MUSCOVY DUCKS (CAIRINA MOSCHATA) IN NIGERIA

While there are studies that describe the biometric traits and phenotypic variations in Muscovy ducks in Nigeria, there are limited studies that employ a multivariate approach to depict the phenotypic variability of Muscovy ducks in Nigeria. Therefore, this study aimed to explicate genetic variabilities within C. moschata using qualitative and biometric traits. This study used a multivariate statistical method to phenotypically characterise locally adapted Muscovy duck populations from seven ecogeographical locations in Ibadan, Nigeria. Four qualitative traits (eye colour, bill colour, bean colour and shank colour) and eleven biometric traits (head length, neck length, body length, wings length, shank length, toe length, thigh length, bill length, breast length, breast width and bodyweight) were evaluated in 201 ducks (109 males and 92 females). To study the possible effects of geographical locations on selected phenotypes, frequency distribution, univariate analysis, stepwise and canonical discriminant analyses and cluster analysis were performed. The association between body weight (BWT) and other biometric traits was assessed using the Pearson product-moment correlation coefficient. Male ducks (drakes) were generally more abundant than female ducks (hens). The most prevalent colour traits of locally adapted Muscovy ducks were brown eye colour (70.65 %), black bean colour (62.69 %), pinkish white bill colour (45.27 %) and grey shank colour (56.22 %). Overall, ecogeographical location did not significantly affect (p < 0.05) the measured biometric traits. However, across all locations, the sexual dimorphism was favourable in male ducks, with respect to biometric traits. Stepwise-canonical discriminant analysis revealed a substantial intermixing of biometric traits, especially in Molete, Oje, Adogba and Ajibode ducks. Similarly, the cluster analysis, although it separated the birds into different clusters, showed some level of admixture. The small Mahalanobis distance (0.61 − 3.88) suggested that, with respect to location, there was more morphological similarity than dissimilarity between ducks. The correlation analysis revealed that the body weight of ducks can be fairly estimated from other biometric traits due to their positive, statistically significant correlation. In general, the ducks from all seven ecogeographical locations were rather homogeneous than heterogeneous.

Genome-Wide Association Studies Reveal Candidate Genes Associated with Pigmentation Patterns of Single Feathers of Tianfu Nonghua Ducks.

In modern advanced genetics and breeding programs, the study of genes related to pigmentation in ducks is gaining much attention and popularity. Genes and DNA mutation cause variations in the plumage color traits of ducks. Therefore, discovering related genes responsible for different color traits and pigment patterns on each side of the single feathers in Chinese ducks is important for genetic studies. In this study, we collected feather images from 340 ducks and transported them into Image Pro Plus (IPP) 6.0 software to quantify the melanin content in the feathers. Thereafter, a genome-wide association study was conducted to reveal the genes responsible for variations in the feather color trait. The results from this study revealed that the pigmented region was larger in the male ducks as compared to the female ducks. In addition, the pigmented region was larger on the right side of the feather vane than on the left side in both dorsal and ventral feathers, and a positive correlation was observed among the feather color traits. Further, among the annotated genes, WNT3A, DOCK1, RAB1A, and ALDH1A3 were identified to play important roles in the variation in pigmented regions of the various feathers. This study also revealed that five candidate genes, including DPP8, HACD3, INTS14, SLC24A1, and DENND4A, were associated with the color pigment on the dorsal feathers of the ducks. Genes such as PRKG1, SETD6, RALYL, and ZNF704 reportedly play important roles in ventral feather color traits. This study revealed that genes such as WNT3A, DOCK1, RAB1A, and ALDH1A3 were associated with different pigmentation patterns, thereby providing new insights into the genetic mechanisms of single-feather pigmentation patterns in ducks.

Karakteristik Morfologi dan Organ Reproduksi pada Bebek Betina

This research aims to determine the morphology of female ducks from two different feeds andalso determine the reproductive organs in female ducks. The data collection technique was carried out directly by observing the development of the morphological characteristics of the ducks every week. In this study, two female ducks were used with two different feeds, namely 1 duck eating bran and the other duck eating pellets as the main feed. Based on the observations made, it can be concluded that ducks that eat bran (natural feed) and pellets (artificial feed) have a morphology that is not much different from each other, namely they have a slender body shape and a relatively long neck. The main difference lies only in the diet. and the nutritional quality obtained from the food. The reproductive organs of female ducks are located inside their bodies. The main reproductive organs in female ducks consist of the ovaries, oviducts (egg tubes), and cloaca. The ovaries of female ducks generally have an oval shape like small eggs at the end of the cloaca.

Study on Heat Stress Behavior and Blood H/L Ratio of Ducks Fed Diets Containing Mix Strains of Probiotics in Commercial Farms

An experiment has been conducted with the purpose of examining the effect of two kinds of probiotic on the behavior and blood H/L ratio of local ducks kept in commercial farms. The study was conducted in collaboration with the ‘Berkah Abadi’ duck farmer group which keeps the bird under an intensive dry system. The intensive system refers to the ordinary way done by the farmers in which ducks were confined around the farmer’s village with a closed fence so the birds had no access to the outside area, and the amount of feed provided could be controlled and measured. The location was in the coastal area of Tegal City as one of the most famous duck centers in Indonesia. The materials used were 13.4+1.3 months old local laying ducks which were reared by the farmer group. The study used a Completely Randomized Design with treatments consisting of 3 doses of P and P+ probiotics respectively. P contained Lactobacillus sp. combined with Saccharomyces cerevisiae, whereas P+ comprised Lactobacillus sp., Saccharomyces cerevisiae, Streptococcus thermophilus, and Lactobacillus bulgaricus. There were 6 treatment units which were replicated 4 times, so in total there were 24 flocks. Each flock had 50 female ducks; therefore this study involved 1,200 ducks. The treatments were applied each morning, and mixed thoroughly in duck ration. Data collected were heat stress-related behavior, body temperature, and H/L ratio. It was concluded that P and P+ had similar effects on the behaviour and H/L ratio of local ducks kept under commercial management.

Characterization and comparative transcriptomic analysis of skeletal muscle in female Pekin duck and Hanzhong Ma duck during different growth stages using RNA-seq

Duck is an economically important poultry, and there is currently a major focus on improving its meat quality through breeding. There are wide variations in the growth regulation mechanisms of different duck breeds, that fundamental research on skeletal muscle growth is essential for understanding the regulation of unknown genes. The study aimed to broaden the understanding the duck skeletal muscle development and thereby to improve the performance of domestic ducks. In this study, RNA-seq data from skeletal muscles (breast muscle and leg muscle) of Pekin duck and Hanzhong Ma duck sampled at d 17, 21, and 27 of embryo (E17d, E21d, and E27d), as well as at 6-mo-old following birth (M6), to investigate and compare the mRNA temporal expression profiles and associated pathways that regulate skeletal myogenesis of different duck breeds. There were 331 to 1,440 annotated differentially expressed genes (DEGs) in breast muscle and 380 to 1,790 annotated DEGs in leg muscle from different databases between 2 duck breeds. Gene ontology (GO) enrichment in skeletal muscles indicated that these DEGs were mainly involved in biosynthetic process, developmental process, regulation of protein metabolic process and regulation of gene expression. KEGG analysis in skeletal muscles showed that a total of 41 DEGs were mapped to 7 KEGG pathways, including ECM-receptor interaction, focal adhesion, carbon metabolism, regulation of actin cytoskeleton, calcium signaling pathway, biosynthesis of amino acids and PPAR signaling pathway. The differential expression of 8 selected DEGs was verified by qRT-PCR, and the results were consistent with RNA-seq data. The identified DEGs, such as SDC, SPP1, PAK1, MYL9, PGK1, NOS1, PHGDH, TNNT2, FN1, and AQP4, were specially highlighted, indicating their associations with muscle development in the Pekin duck and Hanzhong Ma duck. This study provides a basis for revealing the differences in skeletal muscle development between Pekin duck and Hanzhong Ma duck.

Fatal avian pox in a backyard flock of domestic ducks in Bangladesh

AbstractThis case study describes a fatal avian pox outbreak in a backyard flock of domestic ducks (Anas platyrhynchos domesticus) in Bangladesh. A total of six ducks of varying ages were affected and presented with solid tumour‐like masses on the legs. A 6.5‐month‐old female duck was presented for clinical examination, and a 2 cm3 solid, nodular mass was surgically excised from the left leg. Histopathological examination of the tumour mass revealed marked epidermal hyperplasia with ballooning degeneration and eosinophilic intracytoplasmic inclusion bodies, as well as severe proliferation and necrotising dermatitis, with marked heterophilic and histiocytic infiltration. Electron microscopy revealed numerous dumbbell‐shaped virus particles within the intracytoplasmic inclusion bodies on degenerating keratinocytes, confirming Avipoxvirus infection. This is the first case report of avian pox in ducks in Bangladesh.

Pasteurella multocida causes liver injury in ducks by mediating inflammatory, apoptotic and autophagic pathways

Pasteurella multocida.(PM) infection is a major cause of avian cholera, but the pathogenesis of the disease is unknown. The purpose of this study was to further understand the host response to infection by using a duck model of PM, 20 female ducks were divided into two groups (n = 10). One group was infected with PM, while the other served as an uninfected control group. The ducks were observed after infection and samples were collected for testing. In this study, we report the mechanism of PM-induced inflammation to further mediate apoptosis and autophagic signaling pathways in liver cells. Our results demonstrated that PM infection initially induces hemorrhagic and necrotic lesions in the liver tissue of duck, promoting inflammasome assembly and release, triggering inflammation. The TLR4/NF-κB axis activated and interacted with multiple inflammation-related proteins, including TNF-α and IL-1β, which affected apoptosis and autophagy. Tumor necrosis factor induced hepatocyte apoptosis was implicated in a wide range of liver diseases; the release of TNF-α and activation with NF-κB further incite apoptotic pathways,such as Bax/BCL2/caspase to promote apoptotic genes APAF1, Bax, Caspase3, BCL-2, p53, and Cytc expression. Finally, PM-induced autophagy suppressed liver injury by promoting the Beclin-1, LC3B, p62, and mTOR. Thus, liver injury caused by PM via promoting autophagy was induced. In conclusion, we analyzed the liver injury of ducks infected with PM, and confirmed that inflammation appeared in the liver; this was followed by the intricate interplay between inflammation, apoptosis, and autophagy signaling pathways. The observed results provided a reference basis for studying pathogenic mechanisms of PM-host interactions.

The impact of gender on growth performance, live weight gain, and survival rate in Pekin ducks

This study aimed to investigate the effect of gender on growth performance, live weight gain, and survival rate in Pekin ducks raised in a family-type farm in Kars province. A total of 150 ducklings (62 males, 88 females) were observed from day one. Weight measurements were recorded regularly, and mortalities were noted for survival rate analysis. No significant gender differences were observed in live weight up to 10 weeks of age, indicating comparable growth rates initially. However, at 10, 13, and 16 weeks, male ducks had higher live weights compared to females. Daily live weight gains were significantly higher during the first two weeks, with a decreasing trend as the ducks grew older. Gender significantly affected daily weight gains during the initial two weeks. The influence of gender on weekly live weight gains was not statistically significant. Live weight gains decreased over time, while overall live weight increased. Regression models indicated higher growth rates in males. Survival rates remained high throughout the 16-week period, with no significant difference between genders. The hazard ratio analysis suggested no substantial difference in mortality risk between male and female ducks. In conclusion, gender influenced live weight and daily weight gains in Pekin ducks, with males generally exhibiting higher weights. However, gender did not significantly affect average live weight gain and survival rates.

Comparison of morphology characteristics of F1-hybrid and F2-backcross hybrid of local and Pekin ducks in Indonesia

The purpose of this study was to evaluate the comparison of morphology characteristics of two groups (the F1 and F2 backcross of Local and Pekin ducks at 25 weeks of age) in South Sulawesi Indonesia. The research material used 14 ducks males and 10 ducks females of F1 and 7 ducks males and 14 ducks females of F2-backcross. The data were measured on live weight, shank length, bill length, bill width, wing length, chest circumference, neck length, drumstick length, and thigh length. All mean differences of quantitative data from those two groups were analyzed using Independent T-test. The results showed that the performance of body dimensions of the F1 and F2-backcross of male and female ducks were relatively equal in performance concerning live weight, shank length, bill length, and neck length, respectively. The highest and positive correlation exists between shank length with chest circumference and drumstick (r=0.78) of F1 backcross female duck, between live weight with shank length (r=0.72) of F2-backcross female duck, between shank length with chest circumference (r=0.59) of F1 male duck and between live weight with chest circumference (r=0.84) of F2-backcross male duck, respectively. All measured variables had a coefficient of variation on both generations were less than 15%, except the bill width of the F1 male duck (41.79%) and both sex of thigh length of the F1 duck (24.68% and 23.68%, respectively).

Molybdenum and cadmium co-induce necroptosis through Th1/Th2 imbalance-mediated endoplasmic reticulum stress in duck ovaries

Cadmium (Cd) and excess molybdenum (Mo) pose serious threats to animal health. Our previous study has determined that Cd and/or Mo exposure can cause ovarian damage of ducks, while the specific mechanism is still obscure. To further investigate the toxic mechanism of Cd and Mo co-exposure in the ovary, forty 8-day-old female ducks were randomly allocated into four groups for 16 weeks, and the doses of Cd and Mo in basic diet per kg were as follows: control group, Mo group (100 mg Mo), Cd group (4 mg Cd), and Mo + Cd group (100 mg Mo + 4 mg Cd). Cadmium sulfate 8/3-hydrate (CdSO4·8/3H2O) and hexaammonium molybdate ((NH4)6Mo7O24·4H2O) were the origins of Cd and Mo, respectively. At the 16th week of the experiment, all ovary tissues were collected for the detection of related indexes. The data indicated that Mo and/or Cd induced trace element disorders and Th1/Th2 balance to divert toward Th1 in the ovary, which activated endoplasmic reticulum (ER) stress and then provoked necroptosis through triggering RIPK1/RIPK3/MLKL signaling pathway, and eventually caused ovarian pathological injuries and necroptosis characteristics. The alterations of above indicators were most apparent in the joint group. Above all, this research illustrates that Mo and/or Cd exposure can initiate necroptosis through Th1/Th2 imbalance-modulated ER stress in duck ovaries, and Mo and Cd combined exposure aggravates ovarian injuries. This research explores the molecular mechanism of necroptosis caused by Mo and/or Cd, which reveals that ER stress attenuation may be a therapeutic target to alleviate necroptosis.

Performance of cross-bred (White Pekin × Khaki Campbell) ducks under intensive system of rearing

In the present investigation, the performance of a crossbred (White pekin × Khaki Campbell) duck of meat and egg variety produced through artificial insemination were studied under intensive system of management. A total of 157 day old ducklings were reared in the experimental duck farm with standard management practice of brooding, and growing with balanced feed and health management. However, at 16th wk of age, 30 female ducks were confined to individual cage to record their egg laying performances. The growth performance revealed the significant difference between male and female from 8th to 24th week of age. Most of the body measurement parameters found higher than that of Khaki Campbell and less than that of White Pekin ducks of similar age. The blood biochemistry estimates revealed no variation between male and female ducks except for albumin and calcium wherein the value is highly significant for females. The carcass quality estimates of 20th week male ducks were at par with their age. The average age of sexual maturity was recorded as 131.83±1.65 days and age at 50% egg production in the flock was 139 days. The duck day egg production per cent up to 45th week of age was 80.31±3.44 and it was also recorded that in 108 occasions, one duck laid more than one egg. The egg estimates study of the experimental duck eggs (100 nos) at 40 wks age revealed 62.31± 0.44 g egg weight and 92.378 ± 0.453 as Hague unit scale. The study revealed that the production and reproduction parameters of the cross-bred (WP × KC) ducks may meet the expectation of farmers to be benefitted through both meat and egg production.

IDENTIFICATION OF QUALITATIVE AND MORFOMETRIC CHARACTERISTICS OF 4 MONTHS OLD KERINCI DUCKS


 
 
 The purpose of this study was to determine the qualitative and morphometric characteristics of male and female Kerinci ducks aged 4 months. The research material was 72 Kerinci ducks consisting of 36 males and 36 females. The method used is the experimental method. Data on the quantitative characteristics of body sizes were analyzed using the mean difference test (t-test). Main Component Analysis (MCA) was used to identify body size and body shape in male Kerinci ducks and female Kerinci ducks. Data processing used statistical software Minitab version 18. The results showed that there were differences in the qualitative characteristics of male and female Kerinci ducks, namely the color of the head, neck, chest and tail feathers. The body sizes of male Kerinci ducks were significantly different (P<0.05) higher than that of female Kerinci ducks. In conclusion, the qualitative characteristics of male and female Kerinci ducks can be distinguished on the color of neck feathers, chest feathers, tail and head feathers. In male Kerinci ducks, it was found that there was a difference with the minister’s decision, namely the color of the neck feathers. The male Kerinci duck has a higher body size than the female Kerinci duck. Body size markers in male and female Kerinci ducks were chest circumference and body shape markers, namely tibia length in males and femur length in females.
 
 

Effect of Zinc Supplementation in the Diet on Sikumbang Janti Female Duck Performance, Carcass, Digestive Organs, and Intestinal Morphology

The research aimed to evaluate the effect of Zn supplementation in diet of Sikumbang Janti female duck on its performance, carcass, digestive organs, and intestinal morphology. The study used 96 female ducks aged 8 weeks. This research used a completely randomized design with four treatments (0, 30, 60, and 90 mg Zn/kg), each treatment was repeated four times. Performance, carcass, digestive organs, and intestinal morphology were observed. The results showed that Zn supplementation significantly (P0.05) affected body weight, body weight gain, feed conversion ratio, carcass weight, abdominal fat, and intestinal morphology, but it did not affect (P0.05) feed consumption, carcass percentage, and digestive organs. In conclusion, supplementation of 60 mg Zn/kg in the diet improved performance, intestinal morphology, and the health of visceral of Sikumbang Janti female ducks aged 8 to 16 weeks.

Computed tomographic and magnetic resonance imaging anatomy of the coelomic cavity in market-age commercial Pekin Ducks (Anas platyrhynchos domesticus).

Approximately 27 million ducks are raised commercially in the US each year and Pekin ducks (Anas platyrhynchos domesticus) are the most commonly raised breed. Additionally, an increasing number of Americans are raising small flocks of poultry, which often include ducks, in their own backyards. This creates a need to better understand the imaging anatomy of ducks. However, in avian species, superimposition of organs limits evaluation of the coelomic cavity using the most common imaging modality, radiography. The use of cross-sectional imaging including computed tomography (CT) and magnetic resonance imaging (MRI) has increased in veterinary medicine research and clinical use. An anatomic atlas is essential for guiding research and diagnostic imaging. To date, no CT or MRI atlas exists for Pekin ducks. The purpose of the study is to generate a CT atlas of market-age Pekin ducks as well as CT attenuation values and measurements of coelomic organs with corresponding gross and MRI images. A total of 20 market-age, commercial Pekin ducks were imaged. Five male and five female ducks were imaged with CT; four of these ten ducks, two male and two female, were frozen and sliced in approximately 5 mm transverse sections for gross anatomic reference images. Six additional ducks, three male and three female ducks, were dissected to measure major organs. Four additional ducks were imaged using CT and MRI and necropsied for gross anatomical comparisons and landmarks. The atlas contained here may be used for future research projects and clinically to aid in diagnosis of disease in ducks.

Renal adenocarcinoma found in a clinically lame marbled duck (Marmaronetta angustirostris)

AbstractLameness is a frequent reason for captive waterfowl to be presented to a veterinarian. This case report describes unilateral right hindlimb lameness in an 11‐year‐old, female marbled duck kept at a zoological collection in the United Kingdom. Although the bird was euthanased after clinical and radiographic examination, both supported a diagnosis of degenerative joint disease, postmortem examination revealed a renal adenocarcinoma, which possibly put pressure on the nerves of the left hindlimb and may have interfered with the duck's mobility. This case highlights that coelomic issues may lead to lameness in avian patients and, as such, clinicians must consider changes in soft tissue structures alongside skeletal abnormalities when evaluating radiographic images in cases of lameness.

The phenotypic diversity in the production performance of Alabio ducks (Anas platyrhynchos Borneo) in South Kalimantan, Indonesia.

This study aimed to examine the diversity of phenotypic characteristics of female Alabio ducks (Anas platyrhynchos Borneo) and their eggs in South Kalimantan, Indonesia. A total of 200 18-month-old ducks and 300 eggs were selected using a survey method with multistage random sampling. These samples were obtained from two districts in the province of South Kalimantan [Banjar (BJ) districts and Tanah Laut (TL)]. The observed data were analyzed descriptively with variations using the independent t-test for each location. Principal component analysis (PCA) was deployed to assess the overall variance and define variables with greater discriminatory power between individuals. The observations on the body's physical characteristics and the eggs of Alabio ducks showed significant differences between ducks from BJ and TL areas (p < 0.05) except for yolk diameter, albumen height, albumen index, and Haugh unit (HU) (p > 0.05). Most egg quality traits from BJ were greater than those from TL, which include egg weight, egg length, egg width, yolk weight, albumen weight, shell weight, shell thickness, and egg shape index. The PCA revealed medium-to-high communalities in the phenotypic body characteristics of Alabio ducks and their eggs. Significant physical characteristics and egg quality differences were found between the two locations, except for the albumen index and HU, with substantial variability within each trait. These traits could explain the total variation in the phenotypic characteristics of female Alabio ducks.

Quantitative and Qualitative Characteristics (Phenotype) of Laying Ducks in Ternate City as the Basis for Local Livestock Breeding in North Maluku Province

Duck is a producer of animal protein whose production is eggs and meat, is a type of poultry that has the potential to be developed in the city of Ternate. However, until now there has been no characterization research in Ternate City. The aim of the study was to determine the phenotype characteristics as the basis for breeding local cattle in North Maluku. The materials used were adult male and female laying ducks, the variables observed were male ducks, qualitative characteristics were the character of coat color, beak color, eye color and quantitative characteristics were measured body size including femur length, tibia length, shank length, shank circumference, length wingspan, chest length, chest width, chest depth and hip width. calculating the mean formula, standard deviation and coefficient of diversity, qualitative characteristics of ducks using relative frequency analysis. The results showed that the quantitative characteristics of female ducks were more similar than those of male ducks. While the qualitative nature, the color is relatively the same both males and females have brown fur, only one is blackish brown, the skin color of the legs and beak is more dominantly black and brown compared to yellow, black yellow and brown yellow.

Population size and breeding ecology of Yellow-billed Duck (Anas undulata, Dubois 1839) in Chelekleka wetland, Ethiopia

Yellow-billed Duck (Anas undulata) is a monomorphic African endemic dabbling duck protected by the Conservation of African-Eurasian Migratory Water birds Agreement. This study was conducted to investigate the population size and breeding ecology of Yellow-billed Duck in Chelekleka wetland, Ethiopia from November 2020 to October 2021. Census was conducted during early morning from 6:30 - 10:00 hrs and late afternoon from 15:30 - 18:00 hrs twice per week when the birds are active. Direct observations as well as nest and egg morphometry measurements were conducted to collect data on breeding ecology of Yellow-billed Ducks. During the study period, eight active nests were identified and followed. Data were analysed using R version 4.2 software. A maximum of 315 individuals of Yellow-billed Ducks were counted, with a significantly high population size during dry season compared to wet season (Z = - 10.85, df = 63, p &lt; 0.001). The female Yellow-billed Duck built a nest made up of herbs, defoliated leaves, dried grasses and thin twigs. The nest is circular shaped with a 26 - 32 cm in diameter and 7 - 11 cm in height. They laid eggs that are light brownish. Clutch size ranged from 5 - 8 eggs. The mean egg length, breadth and weight were 45.38 ± 1.65 mm, 39.17 ± 0.58 mm, and 45.4 ± 1.7 gm, respectively (n = 21). The average incubation period per nest was 19 ± 0.82 days (n = 4) with a high hatching success (98.1 %; n = 53). Supporting a considerable number of Yellow-billed Ducks, Chelekleka wetland is ecologically important for breeding and other related ecological requirements of the species. However, anthropogenic factors such as; burning of nesting bushes, wetland degradation, and agricultural expansions are highly threatened their survival. Therefore, sustainable conservation intervention is needed to minimize the threats on the species and its habitat.

Short Communication: Polymorphism of collagen type X (COLX) gene and their association with egg production traits and egg weight in Alabio and Mojosari ducks

Abstract. Kumalawati DS, Maharani D, Sari APZNL, Pratomo GH, Sasongko H, Fathoni A, Susanti T. 2023. Short Communication: Polymorphism of collagen type X (COLX) gene and their association with egg production traits and egg weight in Alabio and Mojosari ducks. Biodiversitas 24: 1518-1523. Type X collagen (COLX) is non-fibrillar collagen expressed in the white isthmus of the avian oviduct and plays a role in egg formation. This study aimed to identify COLX gene polymorphism and its association with egg production and egg weight in Alabio (Anas platyrhynchos Borneo) and Mojosari ducks (Anas platyrhynchos Javanicus). Blood samples of 100 female ducks were collected, and their deoxyribonucleic acid (DNA) was extracted. In addition, a 220 bp fragment of COLX gene was amplified using the polymerase chain reaction (PCR) method and sequenced for single nucleotide polymorphism (SNP) identification and genotyping. Data analysis was performed to calculate genotype and allele frequencies, and an independent sample t-test was used to examine the association between genotype and egg production and egg weight of each individual. Three genotypes (CC, TT, and CT) of SNP g.74C/T were detected in both breeds. Allele C (0.77) was dominant in Alabio population; otherwise, allele T (0.81) dominated Mojosari population. The frequency of CC (0.59) was highest in Alabio ducks, followed by CT (0.37) and TT (0.04), while TT (0.65) was highest in Mojosari ducks, followed by CT (0.33) and CC (0.02). Meanwhile, association analysis showed that ducks with CC genotype had significantly higher egg production at 28 and 34 weeks in Alabio than those with CT genotype (p&lt;0.05). These results indicate that COLX is an effective genetic marker for a breeding program to increase egg production in Alabio ducks.

Resequencing of a Pekin duck breeding population provides insights into the genomic response to short-term artificial selection.

Short-term, intense artificial selection drives fast phenotypic changes in domestic animals and leaves imprints on their genomes. However, the genetic basis of this selection response is poorly understood. To better address this, we employed the Pekin duck Z2 pure line, in which the breast muscle weight was increased nearly 3-fold after 10 generations of breeding. We denovo assembled a high-quality reference genome of a female Pekin duck of this line (GCA_003850225.1) and identified 8.60 million genetic variants in 119 individuals among 10 generations of the breeding population. We identified 53 selected regions between the first and tenth generations, and 93.8% of the identified variations were enriched in regulatory and noncoding regions. Integrating the selection signatures and genome-wide association approach, we found that 2 regions covering 0.36 Mb containing UTP25 and FBRSL1 were most likely to contribute to breast muscle weight improvement. The major allele frequencies of these 2 loci increased gradually with each generation following the same trend. Additionally, we found that a copy number variation region containing the entire EXOC4 gene could explain 1.9% of the variance in breast muscle weight, indicating that the nervous system may play a role in economic trait improvement. Our study not only provides insights into genomic dynamics under intense artificial selection but also provides resources for genomics-enabled improvements in duck breeding.