RETRACTED: Growth performance, carcass characteristics, and selected meat quality traits of two strains of Pekin duck reared in intensive vs semi-intensive housing systems

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). The article has been retracted at the request of the Editor-in-Chief. The article was derived from the thesis of one of the authors: Utjecaj genotipa i sustava drzanja na kvalitetu pacjeg mesa H. Mahmutovic Faculty of Agriculture of Osijek UDK 637.5’65: 636.082(043) view (nsk.hr) The thesis was not acknowledged in the article, contrary to requirement by the journal. Concerns raised by the Thesis supervisors (Drs. G. Kralik and Z. Kralik) were shared with the corresponding author and the different institutions involved. The analysis performed by the journal concluded that the published article and the thesis report a different number of replicates per treatment (n= 6 vs n=3) and differ in their description of batches of animals delivered at the experimental facilities and starting the experiment at different times (n=1 vs n=3). Overall the analysis of the evidence provided indicates that the statistical model applied to the data is not appropriate to the experimental design. As a result, the study is not reproducible, and findings cannot be considered as reliable. Authorship issues were identified. The thesis supervisors were not associated to the publication. Several co-authors (M. Starčević*, H. Mahmutović, N. Glamočlija, M. Bašić, R. Mitrović, R. Marković, M. Bošković, M.Ž. Baltić) recognised that their contributions were erroneously declared so their authorship remains questionable. The Financial Support Statement is incomplete. Evidence was provided that other sources also contributed to financing the study. Apologies are offered to readers of the journal for any inconvenience this may cause.

Mineral requirements in ducks: an update

Mineral nutrition plays a critical role in growth and bone mineralization in meat ducks as well as reproductive performance in duck layers and duck breeders. In addition to improving production performance parameters, minerals are also essential to support several enzymatic systems to enhancing antioxidant ability and immune function. This review explores the biological function and metabolism of minerals in the body, as well as mineral feeding strategy of various species of ducks. Topics range from mineral requirement to the physiological role of macroelements such as calcium and phosphorus and microelements such as zinc and selenium, etc. As with the improvement of genetic evolution and upgrade of rearing system in duck production, mineral requirements and electrolyte balance are urgent to be re-evaluated using sensitive biomarkers for the modern duck breed characterized by the rapid growth rate and inadequate bone development and mineralization. For duck breeders, mineral nutrition is not only required for maximal egg production performance but also for maintaining normal embryonic development and offspring's performance. Therefore, the proper amounts of bioavailable minerals need to be supplemented to maintain the mineral nutritional state of duck species during all phases of life. In addition, more positive effects of high doses microelements supplementations have been revealed for modern meat ducks subjected to various stresses in commercial production. The nutritional factors of mineral sources, supplemental enzymes, and antinutritional factors from unconventional ingredients should be emphasized to improve the effectiveness of mineral nutrition in duck feed formulation. Organic mineral sources and phytase enzymes have been adopted to reduce the antagonistic action between mineral and antinutritional factors. Therefore, special and accurate database of mineral requirements should be established for special genotypes of ducks under different rearing conditions, including rearing factors, environmental stresses and diets supplemented with organic sources, phytase and VD₃.

Growth performance, carcass composition, leg bones, and digestive system characteristics in Pekin duck broilers fed a diet diluted with whole wheat grain

A total of 270 Pekin ducks were reared for 49 d to determine the effect of feeding a diluted complete commercial wheat grain diet on live weight, feed intake and conversion, carcass, leg bone, and digestive system traits. Different feeding regimes had a significant effect on the body weight of the ducks aged 35 d and the feed conversion ratio in the period between days 22 and 35 of rearing. Dilution of a complete commercial diet with whole wheat grain had no significant influence on the final live weight (day 49), feed intake, and feed conversion ratio during the entire rearing period. Ducks fed a diet with whole wheat grain had a significantly higher dressing percentage after higher percentage of pectoral muscles, skin with subcutaneous fat, abdominal fat, as well as a significantly lower percentage of carcass remainders at the age of 49 d. Dilution of a complete commercial diet with whole wheat grain had no impact on the length of the respective intestinal sections nor on the weight and percentage share of gizzard, liver, heart, and spleen. However, it significantly lowered the fracture strength of the tibiotarsus, and decreased some dimensions of the femur and tibiotarsus.

Growth Performance, Body Measurements, Carcass and Some Internal Organs Characteristics of Pekin Ducks

Simple Summary

The protection and conservation of native poultry breeds, including ducks, is important for biological, cultural, emotional and scientific reasons. The objective of this study was to compare three lines of Pekin ducks for growth performance, body measurements, carcass and digestive system characteristics. The results showed significant differences between the tested lines of ducks in body weight and body measurements, as well as a small number of significant differences in carcass and digestive system characteristics. This may suggest that the tested lines of ducks are different and distinct, mainly in terms of growth and body measurements.

Abstract

Native breeds of ducks have been the subject of many studies in the past, yet the relevant knowledge is still incomplete and needs to be further expanded. The objective of this study was to provide information about differences in growth performance, dressing percentage, carcass composition and digestive morphometry among three lines of Pekin ducks from conservation flocks raised in Poland. The study used 180 sexed Pekin ducks—30 males and 30 females of line P33 (ducks of Polish origin), 30 males and 30 females of line P8 (ducks of Danish origin), and 30 males and 30 females of line P9 (ducks of French origin). Throughout the study (49 d), ducks were confined indoors in six pens. Birds were fed complete commercial diets ad libitum and had unrestricted access to water. The compared lines of ducks differed significantly in body weight from 1 to 49 d of age except of ducks of both sexes at 14 d. At 49 d of age, significant differences were observed between the tested ducks in all the body measurements. Duck genotype had a significant effect on preslaughter body weight, carcass weight and breast muscle, neck and remainders contents, caeca length, liver weight and gizzard percentage. The results show that the tested ducks were significantly different and unique, mainly in terms of the body biometric characteristics.

Effects of Selenium Yeast in Combination with Boron on Muscle Growth and Muscle Quality in Broilers

The effect of selenium yeast in combination with boron on both growth and quality of the muscle in broilers was investigated. A total of 600 one-day-old Arbor Acres broilers were randomly divided into five groups with 120 broilers per group (6 replicates per group). The control group received a basal diet, and experimental groups I-IV received the same basal diet supplemented with 0.3 mg/kg selenium yeast and different doses of boron (0, 5, 10, and 15 mg/kg, respectively). The experiment was conducted for 42 days. Breast and thigh muscles were harvested and muscle quality were examined on day 21 and day 42 of the experiment. Compared to the control group, at 21 days of age, the thigh muscle weight and index were significantly increased in broilers of experimental group II (all P < 0.05); however, the drip loss and shear force of breast and thigh muscle were significantly decreased (P < 0.05). At 42 days of age, the breast muscle weight and index as well as the breast and thigh muscle water holding capability had significantly increased in broilers of experimental group II (all P < 0.05); the breast and thigh muscle drip loss, cooking loss and shear force, and thigh muscle fiber diameter were significantly reduced (all P < 0.05). Breast and thigh muscle fibers were tightly arranged with small cross-sectional areas in broilers of experimental group II. These results suggest that supplementation of 0.3 mg/kg selenium yeast in combination with 5 mg/kg boron in the basal diet can promote muscle growth and improved muscle quality in broilers.

Nutritional requirements of meat-type and egg-type ducks: what do we know?

The demand for duck meat, duck eggs, and associated products is increasing each year. Classic and modern selection programs have been applied to enhance the economic traits of ducks to satisfy the requirements of consumers and enhance the incomes of producers. The nutritional requirements of unselected ducks may not be adequate, however, to fulfill the potential productivity performance of modern birds, including both meat-type and egg-type ducks. In particular, an imbalanced diet is associated with low productive performance and signs of nutritional deficiency (if insufficient nutrients are supplied), as well as with high feed costs and manure problems that reflect flock health and welfare (if excessive nutrients are supplied). Thus, the main aim of this review is to summarize the results of previous studies that estimated the nutrient requirements of meat-type and egg-type ducks in order to evaluate current knowledge and to identify further issues that need to be addressed. In addition, the results obtained in previous studies are compared in order to understand how to lower commercial feed costs, fulfill the genetic potential of selected ducks, protect the environment from pollution, and satisfy the welfare and health needs of ducks.