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Among substances intended to replace growth promoting antibiotics in pig nutrition, non-digestible oligosaccharides or polysaccharides could be potential alternative compounds. Therefore, the influence of beta-1,3-1,6 glucans on bacteriological, biochemical and morphological aspects of the small intestine in weaned piglets was investigated. As sources of beta-glucans, Lentinan (extract of Lentinus edodes mycelium) or dried L. edodes mycelium were added to the diet. Four homogenous groups of 5 newly weaned piglets (4 weeks of age) received one of four diets: control diet (C), C supplemented with Avilamycin (50 mg/kg, positive control), C supplemented with 0.1% of Lentinan and C supplemented with 5% of dried L. edodes mycelium powder. A first group of 10 piglets was euthanized after 11 days and the remaining 10 on day 12 of the experiment. The gastrointestinal tract was divided in segments and samples taken from digesta (stomach, proximal and distal jejunum, caecum), mucosal scrapings (jejunum) and ring shaped tissue samples (1 cm) of proximal and distal jejunum. Bacterial counts were made with digesta and mucosal samples, and short-chain fatty acids (SCFA), lactic acid and ammonia concentrations were determined. Tissue samples of both jejunal sites were embedded in paraffin wax for morphometrical (villus length, crypt depth) and histological observations (numbers of intraepithelial lymphocytes (IEL), goblet cells, apoptotic enterocytes on villi, mitotic cells in crypts). Only the diet containing 5% of dried L. edodes consistently resulted in lower viable counts (ca. 1-2 log10 CFU) of total bacteria, E. coli, streptococci and lactic acid bacteria, and luminal and mucosal effects agreed very well. With this diet, acetate and butyrate concentrations in the distal jejunum were doubled, which is favourable in view of the trophic effect on enterocytes and colonocytes. Villus length (V) was increased with both diets containing beta-glucans while crypt depth (C) was not altered, but V/C was higher. IEL counts were decreased by both diets although bacterial numbers, which is only one parameter of bacterial load, were only diminished with the L. edodes feed. The three supplemented feeds lowered the number of apoptotic enterocytes on the villi, but these numbers were very low (control diet : 44 cells per 100 villi), making clear interpretation difficult. The mitotic index was slightly lower with the L. edodes feed, although not statistically significant. Decreased viable counts observed with the latter diet is a favourable effect as it is accepted that a lower bacterial load causes lower turnover rates of the intestinal epithelial cells, while there is also less competition for specific substrates. A higher V/C ratio, a smaller number of IEL in the epithelium and a lower apoptotic index also indicate slower turnover rate of the mucosa when Lentinan and L. edodes diets were fed. The inconsistent effects observed with Lentinan were probably due to the lo

Three hundred and twenty 30-week old White Leghorn cockerels were housed in individual cages and distributed in a completely randomized factorial design of 5 x 3, with five oil sources (sunflower, soybean, canola, linseed and fish/soybean) and three levels of antioxidant (30, 200 and 400 mg of vitamin E/kg). The aim of this study was to evaluate the effect of the ratio of omega6: omega3 fatty acids by the inclusion of different oil sources and of dietary supplementation with vitamin E on the reproductive performance of cockerels. The use of the fish/soybean combination determined the lowest total antioxidant status of the semen. However, the addition of vitamin E to the fish/soybean-oil-based diet resulted in a linear increase in semen volume, motility and sperm vigour in the 38th week and again in the 52nd week for motility and for sperm vigour and fertility rate in the periods from 50-53 and 41-53 weeks of age. The use of canola oil in the diet resulted in the highest fertility rate during 50-53 and 41-53 weeks of life. Animals receiving the soybean oil based diet showed the smallest fertility rate in the range from 50-53 weeks of age and concomitantly the highest level of cholesterol in the spermatozoa in the range from 47-51 weeks. An interaction between the vitamin E level and soybean oil was verified by the linear increase in motility and sperm vigour at 38 weeks of age. Later, the contrary was shown by a linear reduction in fertility in the periods from 44-46, 47-49 and 41-53 weeks of age. Cockerels that had been fed on the sunflower-oil-based diet showed the highest content of saturated fatty acids in the spermatozoa from 48-51 weeks. An interaction effect was observed between the vitamin E level and sunflower oil shown by a linear increase in the content of saturated fatty acids in the spermatozoa and a linear reduction in the C18: 1omega9, C18 :2 omega6 and PUFA (C18 : 2omega6 + C20 : 4omega6) contents in the spermatozoa at 48-51 weeks and in sperm volume at 52 weeks of age.

Bambara groundnut (Vigna subterannea)--a leguminous root nut, which grows in the tropics and subtropics--was used in an experiment to test its effect on the performance of growing broiler chicks. Performance was measured by monitoring growth, measuring nutrients and energy balances and also by determining nutrient accretion. Twelve-day old broiler chicks, kept in individual metabolic cages, were used in an experiment in which birds were equally allotted (n = 10) into a control (fed high performance diet made up principally of wheat and soybean meal) and 6 test groups fed diets containing 19, 76 and 95% raw or autoclaved bambara groundnuts. All diets were similar in energy, nitrogen and total lipid contents. Diets were also balanced for amino acids, vitamins and minerals in accordance to the specific requirements of the birds. Feed and water were provided ad libitum. Growth performance was monitored over 15 days. Nutrient and energy balances were measured by use of TiO2 as marker. The comparative slaughter technique was implored for the determination of energy and nutrient accretion. The results showed that the level of raw or autoclaved bambara had no significant influence on feed intake. Increasing the bambara level in the diets caused a general linear drop in the performance of the broilers. However, with up to 95% bambara in the diet, the general performance was still above 75% compared to the control. Increasing levels of bambara groundnut caused a decrease in the metabolizability of energy and efficiency of utilisation of ME for BWG. The animals retained more water with increasing levels of raw bambara in the diets while autoclaving increased their DM content to levels comparable to the control. The protein composition of gain was comparable at all levels of inclusion. In general autoclaving improved the performance of bambara.

A study was conducted to determine the effects of extrusion on ruminal, post-ruminal and whole tract digestibility of flaxseed. Extrusion was performed at 155 degrees C with a residence time of 43 s. Two non-lactating Holstein cows fitted with ruminal and duodenal cannulas were used in a randomized complete block design. Results showed that extruded flaxseed had higher (P < 0.05) in situ soluble and lower (P < 0.05) slowly degradable DM and CP fractions than unheated flaxseed. Extrusion increased (P < 0.05) ruminal DM and CP degradability of flaxseed by 7 and 13%, respectively. Ruminal undegraded DM, CP and NDF were all lower (P < 0.05) for extruded flaxseed than for unheated flaxseed. Extrusion increased (P < 0.05) ruminal degradability and reduced (P < 0.05) post-ruminal availability of most amino acids of flaxseed. Whole tract digestibility of DM, CP, NDF and amino acids were higher (P < 0.05) for extruded than for unheated flaxseed. It was concluded that extrusion under the conditions used in the present experiment increases ruminal and whole tract nutrient degradabilities of flaxseed and therefore was ineffective in increasing the post-ruminal supply of amino acids from flaxseed.

The objective of this study was to evaluate the effect of a combined low-protein, low-phosphorus diet supplemented with limiting amino acids and microbial phytase on performance, nutrient utilization and carcass characteristics of late-finishing barrows. 4 x 8 crossbreed barrows were continuously housed in metabolism cages from 70-110 kg BW and were fed diets, either conventional (A) or protein reduced (B) or protein and phosphorus reduced diets (C) based on barley, maize and soybean meal. Diet A (positive control) contained in air dry matter 13% and 10% CP as well as 0.49% and 0.42% P at growth phases I (70-100 kg BW) or 11 (100-110 kg BW), respectively. Diet B was low in CP (11.3%, 8.4%), diet C low in CP and low in P (CP: as B, P: 0.36%, 0.30%). To diet B the limiting amino acids lysine, methionine, threonine and trypthophan were added to meet the levels in diet A. To diet C the limiting amino acids and 800 FTU/kg Aspergillus-phytase were supplemented. At the end of the balance periods the barrows were slaughtered, the carcasses scored and loin chops, ham and Phalanx prima IV were analysed for nutrients and minerals. The CP or P reduction in diets B and C did not generally negatively affect growth, feed efficiency, absolute nitrogen retention or overall carcass performances of the pigs. With the low CP diets B and C, N excretion per unit BWG was decreased by about 23%. The addition of microbial phytase (diet C) increased apparent total tract digestibility of P by about 20%. In spite of 30% reduction of P intake (diet C), the absolute P retention related to 1 kg BW did not differ between treatments. Thus, phytase supplementation in diet C reduced P excretion per unit BWG by about 33%. Phytase raised apparent digestibility of Zn by about 20% but not Ca digestibility. Generally the carcass traits and meat characteristics were not affected by any of the diet strategies. Mineralization of the Phalanx prima IV was also similar in all treatment groups. However, phytase supplementation led to significantly increased zinc concentration in bones (25%). In contrast, Fe incorporation into the Phalanx prima IV was not affected. In general, the feeding regimen introduced in this experiment offers substantial benefits in maintaining a sustainable environmental-friendly pork production even at the stage of late-finishing barrows.

Silages from five ripened varieties of silage maize with dry matter contents ranging between 275 and 410 g/kg were prepared in five laboratory experiments. Whole-plant maize was fermented at 22 degrees C and silages were then stored at the same temperature for 4 months. Spontaneously fermented silages were prepared as control variants and compared with silages inoculated with commercial strains of Lactobacillus plantarum, Lactobzcillus buchneri and a mixed preparation Microsil containing L. plantarum, Lactobacillus casei, Enterococcus faecium and Pediococcus pentosaceus. The starter cultures were applied at doses 5 x 10(5) and 5 x 10(6) CFU/g of chopped maize. Seven biogenic amines and polyamines were extracted from silages with perchloric acid and determined as N-benzamides by micellar electrokinetic capillary chromatography. Common chemical criteria of silage quality were also determined. All three inoculants, mainly at the higher dose, decreased significantly contents of tyramine, putrescine and cadaverine, three undesirable amines occurring at the highest levels. L. plantarum was the most effective. Contents of histamine and tryptamine were low in all experimental silages. Also relatively low were levels of polyamines spermidine and mainly of spermine.

Eighteen cats were used to compare the urine acidifying properties of sodium bisulphate to phosphoric acid. Acidifying agents were added at one of three concentrations (0.4, 0.6, or 0.8%, as-is basis). Cats were offered a commercial diet to determine basal urinary pH, and then again for a 1 week period between blocks 1 and 2. Cats were acclimated to the diets for 6 days, and urine samples were collected on day 7 at 0, 4, and 8 h postfeeding to obtain pre- and postprandial urinary pH. Intakes of diets containing sodium bisulphate tended (P < 0.07) to be lower than intakes of diets containing phosphoric acid. Cats consuming the 0.8% phosphoric acid diet had higher (P < 0.05) food intakes than cats consuming either the 0.4 or 0.6% phosphoric acid-containing diets. There was significant (P = 0.01) linear and quadratic response for food intake in cats consuming the sodium bisulphate-containing diet. Cats consuming the 0.4 and 0.8% phosphoric acid-containing diets tended (P = 0.07) to have higher water intakes than cats consuming the 0.6% phosphoric acid-containing diet. There were no differences (P > 0.05) in urine pH and specific gravity between cats fed the different acidifier types. Cats consuming the 0.6% phosphoric acid-containing diet tended (P = 0.07) to have a higher urine pH 8 h post-feeding than cats consuming the 0.4 and 0.8% phosphoric acid-containing diets. Urine pH was highest at 4 h post-feeding except for cats fed the 0.4% sodium bisulphate- and the 0.6% phosphoric acid-containing diets. No differences (P > 0.05) between acidifiers were found in faecal score or in faecal dry matter and organic matter concentrations. A quadratic response was detected in faecal score for cats consuming the phosphoric acid-containing diets. Cats consuming the 0.6% phosphoric acid diet tended (P = 0.06) to have a lower faecal score than cats consuming the 0.4 and 0.8% phosphoric acid diets. For faecal dry matter, a linear trend was detected in cats consuming the sodium bisulphate (P = 0.08) and phosphoric acid-containing (P = 0.04) diets. Sodium bisulphate and phosphoric acid generally behaved in a similar fashion when incorporated in dry cat diets.

The absorption, metabolism and excretion of 3-acetyldeoxynivalenol (3-aDON) in pigs were studied. Pigs with a faecal microflora known to be able to de-epoxidate trichothecenes were used in the experiment. The pigs were fed a commercial diet with 3-aDON added in a concentration of 2.5 mg/kg feed for 2.5 days. No traces of 3-aDON or its de-epoxide metabolite were found in plasma, urine or faeces. Deoxynivalenol (DON) was detected in plasma as soon as 20 min after start of the feeding. The maximum concentration of DON in plasma was reached after 3 h and decreased rapidly thereafter. Only low concentrations close to the detection limit were found in plasma 8 h after start of the feeding. A significant part of the DON in plasma was in a glucuronide-conjugated form (42 +/- 7%). No accumulation of DON occurred in plasma during the 60 h of exposure. The excretion of DON was mainly in urine (45 +/- 26% of the toxin ingested by the pigs) and only low amounts of metabolites of 3-aDON (2 +/- 0.4%) were recovered in faeces. De-epoxide DON constituted 52 +/- 15% of the total amount of 3-aDON-metabolites detected in faeces. The remaining part in faeces was DON. DON was still present in the urine and faeces at the end of the sampling period 48 h after the last exposure. The results show that no de-epoxides are found in plasma or urine in pigs after trichothecene exposure, even in pigs having a faecal microflora with a de-epoxidation activity. The acetylated form of the toxin is deacetylated in vivo. Furthermore, the experiment shows that the main part of DON is rapidly excreted and does not accumulate in plasma, but a minor part of the toxin is retained and slowly excreted from the pigs.

A study was conducted to determine the effects of stage of maturity on ensiling characteristics and ruminal nutrient degradability of oat silage. Oat was field grown and forage was harvested at the boot or soft dough stage and ensiled in mini-silos for 0, 2, 4, 8, 16 and 45 days. Two lactating Holstein cows fitted with ruminal fistulas were used determine ruminal nutrient degradability. Regardless of the stage of maturity, ensiled forages went through a rapid fermentation with a sharp decline in pH during the first 2 days of ensiling. Extensive proteolysis took place between 0 and 2 days as indicated by a reduction in true protein and neutral detergent insoluble protein (NDICP) and an increase in non-protein nitrogen (NPN). Chemical analysis of the 45 days silage showed that stage of maturity had no effect on neutral detergent fibre (NDF) and acid detergent fibre (ADF) of oat silage. However, oat harvested at the boot stage contained more crude protein (CP) and less starch than that harvested at the soft dough stage. Distribution of protein fractions showed that oat harvested at the boot stage contained lower NPN, NDICP and acid detergent insoluble protein than oat harvested at the soft dough stage. Results of the in situ incubation experiment indicated that oat harvested at the soft dough stage had lower ruminal dry matter (60.6 vs. 66.4%). CP (81.3 vs. 88.7%) and NDF (35.4 vs. 42.2%) degradabilities than oat harvested at the boot stage. It was concluded that chemical composition and ruminal nutrient degradability of oat silage are significantly influenced by stage of maturity.

Two experiments were conducted to investigate the effects of increasing concentrations of supplemental purified soybean agglutinin on performance, apparent nitrogen digestibility, plasma insulin and cholecystokinine (CCK) levels in rats as well as on the growth of the small intestine and pancreas. In Experiment 1, a 10-day nitrogen balance trial was conducted with 24 male Sprague-Dawley rats (mean BW 85 g) that were randomly allotted to one of four dietary treatments. Rats in each group were provided daily with 7 g of a casein-cornstarch based diet (control) or a diet supplemented with purified soybean agglutinin at 0.4, 0.6 or 0.8 mg/g. Urine and faeces were collected daily and stored at -20 degrees C until analysis. In Experiment 2, 30 male Sprague-Dawley rats (mean BW 75 g) were divided into five groups for a 20-day growth experiment. Each rat was fed daily 7 g of a casein-cornstarch based diet (control) or a diet supplemented with purified soybean agglutinin at 0.4, 0.8, 1.2 or 2.0 mg/g. All experimental diets were adjusted to contain a similar level of nutrients. Results from the two experiments showed that supplementation of soybean agglutinin below 2.0 mg/g diet had no significant effect on rat performance. However, rats receiving 2.0 mg soybean agglutinin per gram of diet showed a significant reduction in weight gain compared to the control group. Incorporation of soybean agglutinin in the diet reduced apparent nitrogen digestibility and the retention of dietary nitrogen by increasing nitrogen loss from the faeces and urine. In addition, plasma CCK level increased with increasing inclusion of soybean agglutinin in the diet. On the contrary, the plasma insulin level declined as soybean agglutinin level increased. Soybean agglutinin induced a polyamine-dependent hyperplastic and hypertrophic growth of the small intestine and pancreas by increasing the contents of protein, RNA and DNA, though the increase in weight of small intestine was not significant. Furthermore, 1.2 and 2.0 mg soybean agglutinin per gram of diet promoted proliferation of the jejunum mucosa, while the structure of the brush border epithelium of small intestinal had no damaging change and no diarrhoea was observed in any treatment group. Based on these results, supplementation of low doses of soybean agglutinin or soy protein to parenterally-fed animals affected by atrophic small intestine may promote small intestinal growth.