Dynamics of yolk sac content absorption and intestine development in ducklings fed mixtures with increasing dietary methionine level.

The experiment was carried out with ducklings fed-control feed mixture (Met level 0.3%) and mixtures supplemented with dl-methionine at the dose of 0.03 (II); 0.07 (III) 0.12 (IV) and 0.18% (V). In 5 h post-hatch (12 birds) and on days 3, 4, 6 always 18 birds were taken out from each treatment and killed, then the yolk sac (YS) and intestine were removed. The weight and chemical composition of YS residues (in them also amino acids) were analysed. Moreover on days 1, 3, 4 and 6, the amino acid pattern of YS residual protein was elaborated as well as length and weight of intestine were recorded. Increased doses of supplemental Met improved body weight gain after 4 days of ducklings life. All determined parameters were not affected by treatment. Development of intestines, yolk sac weight and yolk sac composition (DM, fat, protein, amino acid composition) changed with age; however, without any clear effect from dietary methionine level. No differences between sex and analysed parameters were stated.

Effect of increased methionine level on performance and apparent ileal digestibility of amino acids in ducks.

The experiment was conducted with 960 one-day-old ducklings fed mixtures (I control - 0.28% methionine) additionally supplemented with DL-methionine (DL-Met) at amounts: 0.03% (group II), 0.07% (III), 0.12% (IV) and 0.18% (V). The performance, carcass quality and apparent ileal digestibility of amino acids as the criterions of methionine (Met) effectivity were considered. The analysis of growth and development of ducks as an effect of diversified DL-Met supplements indicate that increased content of this amino acid in the diets has not affected clearly the performance parameters. The body weight of 21-day-old ducklings was significantly affected only by the level of 0.12% of added Met in comparison to control group. On day 42, the differences among groups were negligible; only the addition of 0.12% DL-Met has increased the body weight by 2.4% when compared with control (p > 0.05). Feed conversion estimated for a period of 1-42 days has not been influenced by Met supplementation. The indistinct, however, visible tendency of better ileal amino acids' apparent digestibility (for Asp.a.,Thr, Ser, Glu, Lys) was noted in the groups fed supplemented diets. Application of 0.07% and 0.18% of DL-met, has significantly (p < 0.05) improved the coefficient of cysteine (Cys) apparent ileal digestibility; however, the improvement of Met apparent ileal digestibility has been achieved by the addition of 0.18% Met. The mortality of ducklings in the experiment was very low and varied between 3.15% (II) and 0.0% (groups I and III). In general, application of 0.12% of DL-Met to mixture containing 0.28% Met had positive effect on the productive output of birds and also improved the apparent ileal digestibility of Cys and Met.

Influence of diet type on the inclusion of plant origin active substances on morphological and histochemical characteristics of the stomach and jejunum walls in chicken.

Three hundred and thirty-six 1-day-old male Hubbard HI-Ye broiler hybrids, kept in battery cages, were fed with diets based on maize (groups I and II) or wheat and barley (groups III and IV) and supplemented with or without plant extract (XT* 100 mg/kg) containing 5% carvacrol, 3% cinnamaldehyde and 2% of capsicum oleoresin. The morphological and histochemical examinations were carried out on days 21 and 42 of bird's age. The middle part of glandular part of the stomach and 30 mm long segment from the central part of the small intestine (jejunum) were taken out and then prepared for morphometrical and histochemical assays. Mobilization of mucocytes in superficial epithelium of the glandular stomach and increased secretion of neutral mucopolysaccharides and small amounts of sialomucins with or without local cell disruption with releasing of large amounts of mucus were observed in both 'grain' groups of 21-day-old birds fed with extract. In some animals, particularly those fed mixtures with plant extract, the folds of the proventriculum mucosa were fused into large, unshaped structures. In groups fed with plant extract the mucus secretion intensity and accumulation inside cells of the gastrointestinal mucosa were slightly higher. Morphological changes on gastrointestinal mucosa observed in young chickens fed XT were reduced in older animals. The results of this study showed that the increased releasing of large amounts of mucus and the creation of a thick layer of mucus on glandular stomach and wall of jejunum in chickens fed diets with plant extract could suggest villi-related protective properties of the use of the carvacrol, cinnamaldehyde and capsaicin mixture. This can explain the reduced possibility of adhesion to epithelium and number of Escherichia coli, Clostridium perfringes and fungi in the intestinal content of bird fed with XT supplemented diet. In morphometrical parameters of depth of jejunum crypt and height of villi, the influence of kind of grain and extract supplementation was observed in 21-day-old chickens only. The significant interaction between higher jejunum wall villi layer was observed only in chickens fed on maize diet supplemented with plant extract.

Use of active substances of plant origin in chicken diets based on maize and locally grown cereals.

1. A total of 336 Hubbard Hi-Y broiler hybrids were fed from d 1-41 on diets based on maize or wheat and barley which were supplemented (or not) with 100 mg/kg plant extract consisting of capsaicin, cinnamaldehyde and carvacrol. 2. Body weight was not enhanced, but feed conversion improved by 4.2% on the maize diet and 2.0% on the wheat and barley diet. 3. Plant extract addition enhanced the breast muscle proportion of empty body weight by 1.2% in comparison to control birds. 4. The apparent ileal digestibility of nutrients (crude protein, fibre and amino acids) was not significantly better in birds fed on supplemented diets than in the control group. 5. Reduction of E. coli, Clostridium perfringens and fungi and increase of Lactobacillus spp. were observed in the 41-d-old chickens from the supplemented groups. 6. An increase in the lipase activity in pancreas and intestine wall was found in older birds fed on the plant extract supplemented diets.

Dynamics of yolk sac resorption and post-hatching development of the gastrointestinal tract in chickens, ducks and geese.

Under similar environmental conditions, 100 male Shaver-Starbro hybrid chickens, 100 male Mulard cross-line ducklings and 100 male Landaise goslings kept in 30 metabolic cages from the first day of life (10 birds of each species separately per cage) were chosen for the study. The animals were fed semi ad libitum diets with crude protein content and energy density similar to that used for poultry species, avoiding feed residues. During the first 21 days of life they received starter diets and from day 22 to 42 grower diets. Maize accounted for 23-40% and barley constituted 10-18%. Wheat accounted for 20.0% in starter diets and 10-18% in grower diets. Resorption of yolk sac residues, performance, development of the intestinal tract in young chickens, ducklings and goslings were assessed. During the first 5 days of life intensive absorption of yolk sac ingredients was observed. On day 7, residues of the yolk sac were found in more than 30% of chickens compared with approximately 10% in geese. In ducklings residues of the yolk sac were not found. On day 16 unabsorbed yolk sacs were found in approximately 10% of chickens. Liver and pancreas weighed the highest in geese and in ducks; in chickens the weight of these organs was significantly lower (p < 0.01). The relative values calculated to 100 g of metabolic body weight show that the average small intestine in chickens was significantly longer (p < 0.01) than in ducks or geese. The intestinal tract developed earlier in the chicken than in the water fowl.

Aspects of development of digestive activity of intestine in young chickens, ducks and geese.

The experiment comprised 100 chickens, 100 ducks and 100 geese fed diets based on mixed grains of maize, barley and wheat. Nutrient concentrations in the mixtures were in accordance with the requirements of poultry species. The birds were kept in metabolic cages from the 1st up to the 42nd day of life. The measurements of body weight, activity of alpha-amylase and lipase in pancreatic tissue, enzymatic activity of intestinal wall cells, parameters of carbohydrate fermentations, ileal and total amino acids digestibility were conducted on the 1st, 3rd, 5th, 7th, 28th and 42nd day of life or on the 14th, 28th and 42nd day of life. The pancreas alpha-amylase activity in chickens during the whole period was quite constant; in ducks and geese it was very low, but from the 28th day a dynamic increase in the activity of the pancreatic enzymes was observed in these birds. The activity of lipase was low but from the 28th day of experiment an increase was noted and was much higher in waterfowl than in chickens. The highest caecal concentration of SCFA (Short chain fatty acids) (in total high) was noted in chickens; these values were slightly lower in geese and ducks. A high (70%) ileal amino acids digestibility was seen in very young chickens; during the period of 15-42 days this value amounted up to 73%. In geese, the obtained values were 63% and in ducks 43-61%, with a mean of 55%. Faecal digestibility of amino acids had a mean of up to 86% for all species but the digestibility of single amino acids such as cystine, glycine, histidine and tyrosine was diversified and relatively lower than the others.