Yulong Feng

The Sansui duck is a valuable Chinese genetic resource. However, incomplete exploration of its genetic resources has limited the full utilization of its genetic potential. This study systematically evaluated the growth and carcass performance in 305 Sansui ducks and explored their genetic basis through genome‐wide association studies (GWAS). Body weight (recorded biweekly from 0 to 20 weeks), body measurement traits, and carcass yield traits (measured at 20 weeks) were collected. Growth curve analysis revealed a relatively slow growth rate, with early growth occurring from 0 to 14 weeks and a critical period for weight gain observed at 8–10 weeks. Sansui ducks exhibited small body size with favorable meat production traits: half‐eviscerated yield percentage (HEYP) and eviscerated yield percentage (EYP) both above 70%, while breast muscle percentage (BMP) and leg muscle percentage (LMP) reached 11.99% and 11.01%, respectively. SNP‐based heritability estimates indicated moderate to high heritability for growth and slaughter traits. GWAS identified 222 SNPs associated with growth and slaughter traits, which were annotated to 53 candidate genes, including EFEMP1 , SKAP1 , and MYO19 . Linkage disequilibrium (LD) analysis further pinpointed two key genomic regions on chromosome 28 (1–200 kb and 250–320 kb) influencing multiple traits. These regions harbor critical candidate genes, including the HOXB family and IGF2BP1 , which play important roles in regulating skeletal development, energy allocation, and growth rhythm in poultry. These findings enrich the genetic resource database of the Sansui duck and provide an important theoretical basis for further elucidating the genetic foundation of its growth and carcass performance.

Background: The composition of fatty acids, particularly the content of unsaturated fatty acids (UFA), is closely related to meat quality and flavor in ducks. Result: In this study, 38 fatty acids were detected in the breast muscle of Sansui ducks, yielding 50 distinct fatty acid composition traits. The results showed that the predominant fatty acids were C18:1n-9, C16:0, C18:2n-6, C18:0, and C20:4n-6. Moreover, the breast muscle of Sansui duck was rich in UFA, accounting for 64.01% of the total fatty acids. Genome-wide association analysis (GWAS) identified 158 single nucleotide polymorphisms (SNPs) significantly associated with fatty acid composition traits, which were annotated to 70 protein-coding genes, including LDLRAD3 , ACVR1 , FGF6 , and CASQ2 . Additionally, linkage disequilibrium (LD) analysis revealed a candidate region (10,533,318 − 10,546,189 bp) on chromosome 14, where NSG2 was identified as a key candidate gene influencing C17:1 content. Functional enrichment analysis suggested that pathways such as Adherens junctions and MAPK signaling may play significant roles in fatty acid biosynthesis. Conclusion: These findings reveal the genetic structure of fatty acids composition in the breast muscle of Sansui duck, providing strong evidence for understanding the genetic regulatory mechanisms of fatty acid composition.

This study evaluated the effects of dietary perilla seed meal (PSM) inclusion on growth performance, plasma biochemistry, and breast muscle fatty acid composition in Sansui ducks (Sansui Sheldrake ducks) from 4 to 8 wks of age. A total of 320 male ducks, 29 d old, were randomly assigned to 5 dietary treatments (0, 5%, 10%, 15%, or 20% PSM) with 8 replicates each group and 8 ducks per replicate. Results showed that PSM inclusion up to 20% did not significantly (p > 0.05) affect body weight, daily gain, feed intake, feed-to-gain ratio, or carcass traits. Plasma albumin, total cholesterol, and high-density lipoprotein cholesterol were elevated at 10% PSM inclusion (p < 0.05), while liver function markers remained unaffected (p > 0.05). As expected, dietary PSM supplementation dose-dependently enriched breast muscle n-3 polyunsaturated fatty acids, including α-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid (p < 0.05), and reduced the n-6/n-3 ratio (p < 0.05). These findings indicated that PSM could be incorporated into duck diets at levels up to 20% to enhance the nutritional value of duck meat without adverse effects on growth performance and health, supporting its use as a functional feed ingredient in sustainable duck production.

The aim was to investigate effects of various proportions (0 to 20%) of fermented rapeseed meal (FRSM) on performance, intestinal health, and antioxidant status in Sansui ducks (Sansui Sheldrake ducks). A total of 350 male ducklings, 15 d old, were allocated into five dietary treatments with seven replicate pens of 10 birds per pen. The starter diets had 0, 5, 10, 15, or 20% FRSM that contained 0, 1.08, 2.17, 3.25, or 4.34 µmol glucosinolates (GLS/g of complete feed, respectively, fed from d 15 to d 35. The average daily feed intake (ADFI) and feed conversion ratio (FCR) from d 15 to 35 increased linearly with the dietary FRSM inclusion, with the ducks fed 15 or 20% FRSM diets having higher (p < 0.05) ADFIs and FCRs than the ducks fed 0% FRSM. The dietary FRSM inclusion levels of up to 15% were accompanied by decreased catalase (CAT) and antioxidant capacity (AOC) activities in the livers and jejunum of the ducks at d 35. In addition, the 20% FRSM (4.34 µmol GLS/g diet) decreased the villus height, crypt depth, muscular thickness, and goblet cell counts in the jejunum and ileum. In conclusion, 15 or 20% dietary FRSM (3.25 or 4.34 µmol GLS/g diet) during the grower period in Sansui ducks decreased feed efficiency, disrupted hepatic antioxidant balance, and impaired intestinal morphology and structure. The FRSM inclusion of ≥15% (3.25 µmol glucosinolates/g) impaired feed efficiency and antioxidant activity, while the 20% FRSM (4.34 µmol glucosinolates/g) induced intestinal damage in the growing Sansui ducks.

Puan Panjiang black-bone chickens are renowned for their distinctive traits, deep black coloration, and high-quality protein content, making them a focus of genetic research due to their unique egg-laying abilities. In this study, 110 Puan Panjiang black-bone chickens were used to investigate the effects of natural and artificial selection influencing egg production. Whole-genome resequencing data from red junglefowl (RJF) and high-egg-production (HEP) and low-egg-production (LEP) groups of Puan Panjiang black-bone chickens revealed significant genetic variants associated with egg production traits. Additionally, transcriptome analysis of 47 samples from ovary stroma, small white follicles (SWFs), small yellow follicles (SYFs), and liver tissues from 6 HEP and 6 LEP groups identified differentially expressed genes. Notably, differences in egg production were linked to small yellow follicles rather than ovary stroma or SWFs. Key candidate genes, including TRIM7, CASR, SPTBN5, GAL1, ZP1, IL4I1, and CCL19, were identified as potential contributors to egg-laying performance. This study underscores the genetic diversity within this breed and provides valuable insights for future breeding programs to enhance egg production, supporting the sustainable development of this local resource.

The intensive raising model for meat duck production has widely adopted cascading cages. However, investigations on low-protein diets for Pekin ducks under this model are scarce. Thus, a 3 × 6 factorial experiment was conducted using six dietary crude protein (CP) levels (17.61%, 16.25%, 15.34%, 14.55%, 13.38%, and 12.64%, analyzed) and three cage layers (lower, middle, and upper). The study aimed to examine the effects of dietary CP reduction with crystalline amino acid supplementation on growth performance, carcass traits, and apparent nutrient digestibility in growing Pekin ducks from 21 to 42 days of age housed at different cage layers. A total of 1620 21-day-old Pekin ducks were randomly divided into 18 groups, each with six replicates of 15 ducks per replicate. Ducks were distributed across different cage layers and were fed one of six experimental diets, respectively, each varying in dietary CP levels but maintaining similar dietary energy and amino acid profiles. The results showed that the reduction in dietary CP levels affected growth performance (p < 0.05), while weight gain, feed intake, and feed/gain of Pekin ducks had no difference among 17.61%, 16.25%, and 15.34% CP groups (p > 0.05). As dietary CP decreased, abdominal fat yield increased (p < 0.05), but breast and leg meat yields were unaffected (p > 0.05). CP intake, nitrogen intake, and nitrogen excretion decreased linearly (p < 0.05) with decreasing dietary CP levels, while apparent nutrient digestibility in Pekin ducks increased proportionally (p < 0.05). Additionally, body weight, weight gain, feed intake, CP intake, nitrogen intake, and nitrogen excretion of Pekin ducks decreased (p < 0.05) due to different cage layers, while carcass characteristics remained unaffected by cage layer (p > 0.05). In summary, it is feasible to reduce the dietary CP level with crystalline amino acid supplementation in growing Pekin ducks from 21 to 42 days of age housed in cascading cages, while the cage layers affected growth performance of ducks. Based on broken-line models, it was determined that the optimal dietary CP requirement for achieving maximum weight gain and feed efficiency in growing Pekin ducks is approximately 15%.