Time to Loss of Behavioral and Brainstem Responses of Ducks following Non-Stunned Slaughter

Non-stunned slaughter has been extensively described for other farmed species but there has been limited research on waterfowl. The study assessed 34 White Pekin ducks (Anas platyrhynchos) (study 1) in a non-stunned halal slaughterhouse in Brazil for time to loss of consciousness using various behavioral and brainstem indices (balance, cranial nerve reflexes, and muscle tension) and assessed the relationship between extent of clotting, location of neck cut, level of damage to neck vessels/tissues, and the time to onset of unconsciousness. In addition, operator practices were separately observed and neck pathology following the cut was examined in 217 carcasses after bleeding (study 2). In study 1 following the neck cut there was a wide variation between birds in the time to loss of behavioral and brainstem indices, ranging from 20 to 334 and 20 to 383 s for neck and beak tension, respectively. The median time to loss of balance following the neck cut was 166 ± 14 (22–355) seconds. There was a moderate correlation (R = 0.60 and 0.62) between distance of the neck cut and time to loss of balance and neck tension, respectively. This is the first investigation of the time to loss of consciousness following non-stunned slaughter of ducks in commercial conditions. The findings could be used to improve the welfare of ducks during non-stunned slaughter, such as recommending performance of the neck cut closer to the jaw line and ensuring appropriate waiting periods between slaughter and birds entering the scalding tanks.

Influence on Mycotox® NG effects on relative weights of some internal organs in Pekin ducks with experimentally reproduced aflatoxicosis В1

Contamination of poultry feeds with mycotoxins is a global problem faced by poultry industry due to increased demands and availability of poor-quality cereals. The aim of the present study was to evaluate the beneficial effects of a mycotoxin binder (Mycotox NG) on relative weights of internal organs in Pekin ducks with experimental aflatoxicosis. The birds were divided into one control and six experimental groups (n=10) as follows: group І (0 mg/kg AFB1 without Mycotox NG); group ІI (0.5 g/kg Mycotox NG); group ІІI (1.0 g/kg Mycotox NG); group IV (0.2 mg/kg AFB1); group V (0.4 mg/kg AFB1); group VI (0.2 mg/kg AFB1 + 0.5 g/kg Mycotox NG) and group VII (0.4 mg/kg AFB1 + 1.0 g/kg Mycotox NG). Trial duration was 42 days. It was established that ducks fed AFB1-contaminated feed had increased relative weights of liver, kidneys, pancreas, heart, gizzard and proventriculus compared to the control group. At the same time, the relative weights of immunocompetent organs (thymus, spleen and bursa of Fabricius) were reduced. The addition of Mycotox NG to the feed contaminated with AFB1 compensated partly the changes in relative weights of visceral organs. The results from the present study demonstrated that the tested toxin binder could be effective for reduction of toxic effects of aflatoxins in domestic ducks.

Genome-wide association and selective sweep analyses reveal genetic loci for FCR of egg production traits in ducks

Background As a major economic trait in poultry, egg production efficiency attracts widespread interest in breeding and production. However, limited information is available about the underlying genetic architecture of egg production traits in ducks. In this paper, we analyzed six egg production-related traits in 352 F2 ducks derived from reciprocal crosses between mallard and Pekin ducks. Results Feed conversation ratio (FCR) was positively correlated with feed intake but negatively correlated with egg-related traits, including egg weight and egg production, both phenotypically and genetically. Estimates of pedigree-based heritability were higher than 0.2 for all traits investigated, except hip-width. Based on whole-genome sequencing data, we conducted genome-wide association studies to identify genomic regions associated with these traits. In total, 11 genomic regions were associated with FCR. No genomic regions were identified as significantly associated with hip-width, total feed intake, average daily feed intake, and total egg production. Analysis of selective sweeps between mallard and Pekin ducks confirmed three of these genomic regions on chromosomes 13, 3 and 6. Within these three regions, variants in candidate genes that were in linkage disequilibrium with the GWAS leader single nucleotide polymorphisms (SNPs) (Chr13:2,196,728, P = 7.05 × 10–14; Chr3:76,991,524, P = 1.06 × 10–12; Chr6:20,356,803, P = 1.14 × 10–10) were detected. Thus, we identified 31 potential candidate genes associated with FCR, among which the strongest candidates are those that are highly expressed in tissues involved in reproduction and nervous system functions of ducks: CNTN4, CRBR, GPR63, KLHL32, FHL5, TRNT1, MANEA, NDUFAF4, and SCD. Conclusions For the first time, we report the identification of genomic regions that are associated with FCR in ducks and our results illustrate the genomic changes that occurred during their domestication and are involved in egg production efficiency.

The Full-Length Transcriptome Provides New Insights Into the Transcript Complexity of Abdominal Adipose and Subcutaneous Adipose in Pekin Ducks

Adipose tissues have a central role in organisms, and adipose content is a crucial economic trait of poultry. Pekin duck is an ideal model to study the mechanism of abdominal and subcutaneous adipose deposition for its high ability of adipose synthesis and deposition. Alternative splicing contributes to functional diversity in abdominal and subcutaneous adipose. However, there has been no systematic analysis of the dynamics of differential alternative splicing of abdominal and subcutaneous adipose in Pekin duck. In our study, the Pacific Biosciences (PacBio) Iso-Seq technology was applied to explore the transcriptional complexity of abdominal and subcutaneous adipose in Pekin ducks. In total, 143,931 and 111,337 full-length non-chimeric transcriptome sequences of abdominal and subcutaneous adipocytes were obtained from 41.78 GB raw data, respectively. These data led us to identify 19,212 long non-coding RNAs (lncRNAs) and 74,571 alternative splicing events. In addition, combined with the next-generation sequencing technology, we correlated the structure and function annotation with the differential expression profiles of abdominal and subcutaneous adipose transcripts. This study identified lots of novel alternative splicing events and major transcripts of transcription factors related to adipose synthesis. STAT3 was reported as a vital gene for adipogenesis, and we found that its major transcript is STAT3-1, which may play a considerable role in the process of adipose synthesis in Pekin duck. This study greatly increases our understanding of the gene models, genome annotations, genome structures, and the complexity and diversity of abdominal and subcutaneous adipose in Pekin duck. These data provide insights into the regulation of alternative splicing events, which form an essential part of transcript diversity during adipogenesis in poultry. The results of this study provide an invaluable resource for studying alternative splicing and tissue-specific expression.

Comparison of carcass and non-carcass characteristics of Local and Pekin ducks

The purpose of this study was to evaluate carcass and non-carcass characteristics of local ducks. The research material was carcasses of five local male ducks aged 24 weeks (relative weight of about 1220 g) and five male Pekin ducks of 9 weeks of age (relative weight of about 1440 g) which were kept in the duck cage at the laboratory of Breeding and Genetics, Faculty of Animal Science, Hasanuddin University, Indonesia using intensive housing systems and commercial feed. The research method was all ducks were fasted and rested for 8 hours, slaughtered, carcasses, and parameters analyzed. Parameters measured were weight and percentage of carcass traits (wings, dorsal, thighs, breast, and neck), weight and percentage of non-carcass traits (head, shank, kidney, heart, trachea, esophagus, gizzard, liver, intestine, feathers), three types of weight (live weight, slaughter weight, and carcass weight), percentage of the total carcass, and meat bone ratio (thigh and breast). The results showed that there were no significant differences in all carcass and non-carcass parameters between local ducks and Pekin ducks except for non-carcass parameters, namely head, gizzard, shank, intestine, heart, and trachea. At different ages, Pekin ducks and local ducks showed similar carcass characteristics. These results show that the growth rate of Pekin ducks is faster than that of local ducks. These results become one of the bases and references that local ducks still need a breeding program for improving carcass growth to reach optimum carcass characteristics.

Growth performances and digestability in Pekin ducks fed on a diet containing fermented agro-industrial by-products

Poultry industries in Indonesia develop rapidly in line with the increasing demand for poultry meat and eggs. However, fluctuations in availability and the high price of commercial feed bring about a serious problem for traditional farmers. The objective of this study was to evaluate the effect of feeding a diet containing a fermented mixture of water hyacinth leaves (Eichornia crassipes), rice bran, and blood (WRPS) on the production performance and nutrient digestibility of Pekin ducks. This research was conducted for 6 weeks using 100 Pekin ducks (unsex) aged 2 weeks. This study was conducted using a completely randomized design consisting of 4 treatments and 5 replications. The dietary treatments were T0 (control), T1 (30% WRPS), T2 (40% WRPS), and T3 (50% WRPS). At the end of the feeding trial, one duck from each replicate was put in a metabolic cage for digestibility study, adopting the total collection method. Incorporating WRPS in the diet brought significant differences (p<0.05) in feed intake, body weight gain, feed conversion, and digestibility. It can be concluded that the fermented mixture of water hyacinth leaves, rice bran, and protein of slaughtered waste as much as 30% can be used in the diet of Pekin ducks.

Effects of Pantothenic Acid Supplementation on Growth Performance, Carcass Traits, Plasma Parameters of Starter White Pekin Ducks Fed a Corn–Soybean Meal Diet

This study aimed to evaluate the effects of different dietary pantothenic acid levels on growth performance, carcass traits, and plasma biochemical parameters of starter Pekin ducks from 1 to 21 days of age, as well as the pantothenic acid requirement of starter ducks. A total of 384 one-day-old male white Pekin ducklings were assigned randomly into 6 dietary treatments, each with 8 replicate pens of 8 ducks. Ducks were fed conventional basal corn–soybean diets containing 8.5, 10.5, 12.5, 14.5, 16.5, and 18.5 mg/kg pantothenic acid for 21 days. Growth depression, poor pantothenic acid status, fasting hypoglycemia, and elevated plasma uric acid (UA) content were observed in the ducks fed the pantothenic acid-deficient basal diet (p < 0.05), and these adverse effects were ameliorated by pantothenic acid supplementation. Among all ducks, the birds fed the basal diet with no supplementation of pantothenic acid had the lowest body weight, average daily weight gain (ADG), average daily feed intake (ADFI), breast meat yield, and plasma pantothenic acid and glucose contents (p < 0.05), and the greatest plasma UA content (p < 0.05). In addition, all these parameters showed a linear or quadratic response as dietary pantothenic acid levels increased (p < 0.05). According to broken-line regression, the pantothenic acid requirements of starter male white Pekin ducks for body weight, ADG, and plasma pantothenic acid content were 13.36, 13.29, and 15.0 mg/kg, respectively. The data potentially provides theoretical support for the utilization of pantothenic acid in duck production.