Structure of the digestive system of ducks depending on sex and genetic background

Abstract

The aim of the study was to determine the effect of genotype and sex on body weight, body dimensions, intestinal length and diameter, percentage of intestinal segments, and weight and percentage of the main internal organs of ducks. The study was performed with 80 Pekin ducks, which were kept throughout rearing (1-49 days of age) in a confinement building and fed commercial waterfowl feed ad libitum. After 7 weeks of rearing, 40 ducks (10 drakes and 10 ducks of hybrid line SM3 Heavy and 10 drakes and 10 ducks of hybrid line AF51) were selected for slaughter. Birds were measured for body length and trunk length. During evisceration, the digestive tract and other internal organs were separated. At 7 weeks of age, SM3 Heavy broilers were heavier and had longer body length and trunk length compared to AF51 ducks. Significant differences were found for body weight in females and for body length in males. The AF 51 females were characterized by significantly greater intestinal length to body length and intestinal length to trunk length ratios, whereas AF51 males showed a greater (P ≤ 0.05) body length to trunk length ratio compared to SM3 Heavy birds. Genetic background of the ducks had no significant effect on the length of intestine and its segments, the diameter of different intestinal segments, and the weight and proportion of the gizzard, liver, heart and spleen. The same pattern was observed for the sex of birds except for gizzard weight, which was significantly greater in SM3 Heavy males than females. Duck, genotype, sex, morphometry, digestive tract, internal organsThe digestive system develops at different rates in different poultry species (Lilja 1983). Birds with a higher growth rate are characterized by a more rapid development of the digestive tract. In 7-day-old ducks, the small intestine is 3.7 × heavier and 1.6 × longer than in almost twice lighter turkey poults of the same age (Konarkowski 2006). Over subsequent weeks of life, intestinal length, diameter and surface area of birds increase as does metabolic rate (Lilja 1983;Obst and Diamond 1992). The growth of intestine in birds (intestinal length or intestinal surface area to body weight ratio) is relatively greatest in the first week of life, decreasing with age (Soriano et al. 1993;King et al. 2000). According to Watkins et al. (2004), the morphological and functional growth of the digestive tract in Pekin ducks ceases after 7 weeks of age. Birds show considerable individual variation in the growth of the digestive tract. This is due to many factors, the most important of which include the body size, species, breed, age, sex, and physiological status of the birds. The quantity and quality of ingested food also has a considerable influence (Gille et al. 1999;Szczepańczyk 1999).The aim of the study was to determine the effect of sex and genetic background of Pekin ducks on body weight and length, trunk length, intestinal structure and dimensions, and proportion (g, %) of the main internal organs in the body at 7 weeks of age.

Digestive tract morphometry and breast muscle microstructure in spent breeder ducks maintainedin a conservation programme of genetic resources

“…K2 ducks had significantly shorter body length than KhO1 ducks, and KhO1 ducks significantly shorter intestine than K2 ducks. The intestine length to body length ratios were lower than those reported by Wasilewski et al (2015) for young Pekin ducks. Kokoszyński (2011) observed that four commercial Pekin duck hybrids (Star 53 H.Y., AP54, PP54, and PP45) differed significantly in body weight and length at 7 weeks of age.…”

“…Watkins et al (2004) report, however, that in Pekin ducks, morphological and functional development of the digestive tract is terminated after 7 weeks of age. An earlier study with young Pekin ducks (6-8 weeks of age) found greater (Jamroz et al, 2001;Wasilewski et al, 2015) lengths of individual intestine segments compared to the analysed ducks after two reproductive seasons.…”

“…and AP54 birds. In the study by Wasilewski et al (2015), Pekin SM3 Heavy and AF51 hybrids had longer intestine than the evaluated P9, K2, and KhO1 ducks, which have not been selected for productive traits since the 1980s. In the study by Schmidt et al (2009) with Ross 708 chickens (modern line) and UIUC (heritage line), jejunum and ileum length was around 20 % longer in Ross 708 chickens than in UIUC chickens, which have not been selected since the 1950s.…”

“…The heart and liver percentage of Muscovy and Pekin ducks investigated by Makram et al (2017) was higher than in P9, K2, and KhO1 ducks from this experiment. In another study (Wasilewski et al, 2015), liver and heart percentage was lower and gizzard percentage higher in 7-week old Pekin ducks compared to the ducks aged 110 weeks. Bartyzel et al (2005) noted higher heart percentage (males -0.76 %, females -0.69 %) in wild mallards weighing 1320 g (males) and 1250 g (females) compared to Pekin males (BW = 3128 g, heart = 0.62 %) and females (BW = 3143 g, heart = 0.60 %).…”

Histometerical and Morphological Studies of Digestive Tract and Associated Glands in Domestic Pigeon (Columba livia) with Regard to Age

“…Development rate of digestive tract in birds varies from species to species. Development of digestive tract is related with growth rate of the birds so faster development of digestive tract is characteristic feature of high growing birds (Wasilewski et al, 2015). The development of digestive organs starts just after hatching and the intestine develop rapidly as compare to the other organs of digestive system (Dong et al, 2012).…”