Bi Yu

Bioavailability of iron from amino acid complex in weanling pigs

The objective of the study was to evaluate the iron bioavailability of iron amino acid complex, Availa-Fe 1 compound, as compared to the iron from feed grade ferrous sulfate in weanling piglets. Seventy-two 30-day-old three-way cross piglets, with an average live-weight of 6.41 kg, were randomly allocated into 12 groups of six dietary treatments and two replicates. The control diet (C) included 100 mg kg ˇ1 iron from ferrous sulfate heptahydrate into a basal corn‐soybean‐whey diet. The other dietary treatment groups were supplemented an additional 30, 60, 90, or 120 mg kg ˇ1 of iron from Availa-Fe 1 into the control diet. An additional diet supplemented with 120 mg kg ˇ1 of iron from ferrous sulfate heptahydrate into the control diet was used as a positive control. The piglets fed Availa-Fe 1 as an iron source did not demonstrate a statistically significant improvement in live-weight gains or feed-conversion ratio. The monitored parameters that responded to increases in the level of Availa-Fe 1 supplementation, included pack cell volume, hemoglobin concentration, plasma iron and total iron binding capacity in the blood, hemosiderin and ferritin iron in the liver and spleen. Skin redness with an ‘a’ value in color measurement increased significantly as the level of Availa-Fe 1 supplement increased (p<0.05). The total iron content, heme-iron concentration in the muscle and skin color responded to increases in the level of Availa-Fe 1 supplementation. The bioavailability of iron from Availa-Fe 1 is significantly better compared to ferrous sulfate

Effects of β-glucanase supplementation of barley diets on growth performance of broilers

Abstract A trial was performed to examine the effects of levels of barley substitution and supplementation with β-glucanase in a corn–soybean diet on growth performance and intestinal characteristics of broiler chickens. The experiment involved five levels of barley substituted for corn (0, 125, 250, 500, and 1000 g/kg) and two levels of β-glucanase supplement (with 0.5 g/kg and without) in a factorial arrangement with two replicates. Four hundred day-old commercial strain Harber broiler chickens were randomly allocated into twenty groups of ten dietary treatments for a six-week feeding trial, growing (0–3 week) and finishing period (4–6 week). Unless supplemented with β-glucanase, broilers receiving the diet with more than 250 g/kg of the barley substitute gained slower during the growth period. Conversely, supplementing β-glucanase did not improve total weight gain (0–6 weeks) with a diet of 500 g/kg barley substitution. As the level of barley substitution increased, feed intake in the growing period decreased significantly and viscosity of the intestinal contents increased. However, such an increase did not significantly influence feed conversion (P>0.05). Supplementation with β-glucanase on diet up to 250 g/kg of barley substitute not only enhanced body weight gains of growing broilers, but also improved the live-weight of six-week-old broilers (P

Effects of roxarsone on performance, toxicity, tissue accumulation and residue of eggs and excreta in laying hens

In this study, we examined the effects of a high dosage of roxarsone in the diet on the performance, liver function, and its residue in liver, eggs and excreta of laying hens. Seventy-five 32-week-old layers were selected and randomly allocated into five dietary treatments with three replications for each treatment. Feeding periods were 4 weeks with an additional week for withdrawal. The experimental diets included 0, 11, 22, 44 or 88 mg kg-1 arsenic from roxarsone, respectively. Dietary arsenic above 44 mg kg-1 significantly decreased the egg production and feed intake of the layer (P < 0·05). Layers ceased to produce eggs after two weeks of feeding the 88 mg kg-1 arsenic supplement diet. Where the enzyme activities in the serum, aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase (CK) significantly increased. Also, the liver weight did not only significantly decrease (P < 0·05), but was also damaged on histological examination. Moreover, arsenic residues in the liver, eggs and the excreta significantly increased as dietary arsenic level was increased (P < 0·05). The serum enzyme activities of AST, LDH, CK returns to normal after a week of the drug withdrawal. Arsenic residues in liver, egg and excreta also significantly declined in the withdrawal period (P < 0·05). Furthermore, the hepatic cells were vacuolised from layers treated with 88 mg kg-1 of arsenic.

The morphological changes of intestinal mucosa in growing rabbits

The study aimed to increase understanding of digestive function from the development of the digestive tract from suckling to maturity in rabbits. The relative weights of the digestive tract (in relation to body weight) in different segments increase linearly during the rapid growth period between 2 and 8 weeks of age; thereafter intestinal weight gain is slower. An underdeveloped mucosal histology was observed in the hindgut of suckling rabbits at 2 weeks compared with 4 weeks of age. From SEM micrographs, the small intestinal mucosal villi look more slender and finger-like in the suckling period, thereafter becoming broader or tongue-like or plate-shaped in mature rabbits. The micrographs showed a compact arrangement in the underdeveloped hindgut mucosa at 2 weeks, but after weaning as hindgut fermentation becomes significant the mucosa increased in surface area.

Studies on the protein degradabilities of feedstuffs in Taiwan

Abstract The protein degradabilities of feedstuffs, roughages and by-products that are commonly used in ruminant rations, were measured by the in situ nylon bag method. Four dry dairy cows were fistulated in the rumen for the in situ nylon bag studies. Twenty-eight different feedstuff samples were placed in 4.5 × 6.5 cm nylon bags, and were then incubated in the rumen for different periods of time (0, 2, 4, 8, 12 and 24 h). Under 8% of rumen solid outflow rate, the percentages of the calculated protein degradability were: corn gluten meal, 8.8; feather meal, 29.1; soya pomace, 79.1; brewers grain, 37.1; distillers grain, 53.9; meat and bone meal, 51.9; wheat bran, 76.8; corn, 34.6, respectively. The size of nylon bag was changed to 10 × 20 cm, and the method of bag suspension was also changed, whilst the incubation period was extended two additional periods of 48 and 72 h in the second trial. The results of the protein degradabilities in 8% ruminal outflow rate were as follows: pangola hay. 38.6; soya pomace, 83.3; corn silage, 75.6; rice bran, 52.5; napier grass, 34.7; distillers grain, 60.1; brewers grain, 54.9; alfalfa hay, 71.8; fish meal, 37.5; soybean meal, 68.0; beancurd pomace, 61.7, respectively. All the degradabilities mentioned were uncorrected for influx microbial nitrogen. From the smaller standard deviation of the crude protein disappearance rate in the large nylon bags (trial 2), it recommended the size of the nylon bags is 10 × 20 cm instead of 4.5 × 6.5 cm.

Toxicity, tissue accumulation and residue in egg and excreta of copper in laying hens

To study the effects of a high dietary copper dosage on the performance, liver function, and copper residues in the liver, egg and excreta of the laying hen, seventy-five 28-week-old layers were selected and randomly allocated to five dietary treatments with three replications of five birds each for each treatment. The feeding period was 4 weeks followed by a 1 week withdrawal period. The experimental diets were supplemented with 0, 200, 400, 600 or 800 mg kg−1 copper. The response to copper in the diet in terms of feed intake and egg production fitted a quadratic model (P < 0.05), with 200 mg kg−1 giving a positive response and levels of 400 mg kg−1 and above giving a progressively negative response. Enzyme activities, i.e. aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and creatine kinase (CK) in the serum were significantly (P < 0.05) increased with 600 mg of dietary copper inclusion. Histological examination of livers revealed damage by high dosages (over 600 mg) of dietary copper. Copper residues in the liver and excreta were significantly (P < 0.05) increased as dietary copper increased. The copper content of egg reached a maximum at 400 mg kg−1 dietary copper. Serum enzyme activities of AST, LDH and CK returned to normal after the 1 week withdrawal period. Copper residues in the liver, egg and excreta also declined significantly (P < 0.05) during the withdrawal period.

Effects of crude fibre level in the diet on the intestinal morphology of growing rabbits.

The experiment was conducted to study the effects of 5.5, 8.5, 11.5 and 14.5% dietary fibre levels on growth performance and intestinal villi in growing rabbits. After the 5-week feeding period, food intake and body weight gain increased with increasing dietary fibre levels, feed conversion was highest with 11.5% dietary fibre. Scanning electron microscopy showed slight changes to the jejunal villi and the caecal mucosa in rabbits fed high dietary fibre (14.5%) but the degree of damage was greater in the caecum than the jejunum. Flattened colon villi were seen in the low dietary fibre group whereas high levels showed no effect.

Effects of different sources of dietary fibre on growth performance and apparent digestibility in geese

Abstract Sixty 2-week-old female White Roman geese were used in the first experiment. In the second experiment, eighteen mature female geese were colostomized, placed in metabolism cages and used for a digestion study. The experimental diets for the six different treatments were supplemented with alfalfa meal, barley bran, rice hulls, or purified cellulose, lignin, or pectin, respectively as the major source of fibre. They were formulated into isoenergetic and isonitrogenous diets with 90 g kg −1 of crude fibre. Geese fed the pectin supplemented diet showed significantly less gain in body weight, due to lower feed intake than the other treatment groups ( P P P −1 ). Digestibility of crude protein and gross energy were significantly lower in the diet with a lignin or a pectin supplement ( P

Effect of Echinacea purpurea L. on oxidative status and meat quality in Arbor Acres broilers

BACKGROUND Echinacea purpurea L. (EP) is a popular herbal antioxidant and immunomodulator. The present study was conducted to evaluate the effects of EP on meat quality and oxidative status in broilers. Two hundred and fifty (1-day-old) male broilers (Arbor Acres) were randomly allocated to five groups including the control (corn-soybean meal diet) and 0.1, 0.5, 1.0 and 2.0% EP powder groups, with two replicates per treatment group. RESULTS The results indicated that the addition of 0.5% and 1.0% EP significantly increased water-holding capacity and decreased storage loss of breast and thigh fillets at 35 days old. For fillet colour, L* (lightness) values were lower, and a* (redness) and b* (yellowness) values were higher with EP supplementation. Lower crude fat contents were observed in EP groups in comparison with control at 35 days of age in breast and thigh fillets, respectively. Production of malondialdehyde was slightly reduced in serum of EP supplemented birds compared to the control group. Results for Trolox equivalent antioxidant capacity, catalase and superoxide dismutase were significantly higher for the 0.5, 1.0 and 2.0% EP supplemental groups than control group in serum. Liver and spleen tissues results showed that the antioxidative enzymes activities were higher with EP powder at 35 days of age. CONCLUSION Dried EP can be used as a feed additive to improve the meat quality and oxidative status in Arbor Acres broilers.

Starch Characteristics and Their Influences on In Vitro and Pig Prececal Starch Digestion

The main objective of this research was to study the characteristics of starch granules and their influences on in vitro and pig prececal starch digestion of corn, dehulled barley, wheat, and potato. Scanning electron microscopy was used to study the starch endosperm structure in the parent material as well as in vitro starch digestion. The results showed that corn starch granules were polyhedral, with a diameter ranging from 2 to 10 μm, whereas those of dehulled barley and wheat were spherical, with a diameter ranging from 5 to 20 μm. Potato had the largest starch granules among starch sources reported herein, with oval spheres of 10-50 μm in diameter. In vitro starch hydrolysis showed that starch granules of corn degraded faster than the starch of dehulled barley and wheat, with the potato starch being degraded the slowest. The in vivo digestibility trial using ileal-cannulated pigs confirmed the starch degradation of grains. The in vitro (x, %) and in vivo (y, %) digestibility were highly correlated [y = 6.5304x - 538.48 (R(2) = 0.9924)]. On the basis of the results, in vitro starch hydrolysis might be useful in predicting in vivo prececal starch digestibility. The digestion kinetic characteristics of different starch sources might be employed to evaluate the starch digestive rate at the pig ileum.