• Asian-Australasian Journal of Animal Sciences
• /
• v.4 no.3
• /
• pp.211-218
• /
• 1991

The effects of dietary fiber on true digestibility of amino acids by growing pigs were studied, using semi-purified diets formulated from alfalfa meal, cassava leaf meal, rubber seed meal and leucacna meal at 20% level. A protein-free diet including 5% cellulose was formulated for correcting the endogenous amino acid loss. Across all the diets, arginine was the most digestible while the least at ileal level was threonine; methionine and/or histidine at fecal level respectively. The true digestibility value of amino acids at ileal level were higher than at fecal level except control diet (cellulose). The true digestibility values at ileal level were similar for all diets but differed at fecal level in different magnitude. These results indicate that undigestible compound in individual feedstuff might confound. True digestibility should be studied together for accurate diet formulation as apparent digestibility decreased when their amino acid concentration in the diet was reduced.

• Asian-Australasian Journal of Animal Sciences
• /
• v.4 no.2
• /
• pp.169-176
• /
• 1991

Four fibrous feedstuffs from alfalfa meal (AFM), cassava leaf meal (CLM), rubber seed meal (RSM) and leucaena meal (LM) were included in semi-purified diets for growing pig (45 kg body wt.) at 20%, to investigate the effects of these fiber sources and fractions on amino acid digestibility. Cellulose (C), a purified fiber source was included in another diet at 5% level for comparison. The barrows fitted with ileal T-cannula were used in the digestion trials with latin square design. The digestibilities of amino acids were measured at both terminal ileum and fecal level. NDF and hemicellulose content were the highest in AFM-diet whereas LM-diet had the highest ADF and lignin content. RSM-diet contained the highest crude fiber and cellulose content. The digestibilities of amino acids at ileal level were found the highest with CLM-diet, while LM-diet was the least. At fecal level, control diet and CLM-diet were the highest in amino acid digestibility while AFM-diet was the least. The digestibility of amino acids was higher at ileal than fecal level. The digestibility of arginine was not affected with fiber fractions but was found to be the most disestible across all diets. The most depressed amino acid was methionine at both levels; praline and glycine, in the dispensable amino acid group, were depressed at ileal and fecal level, respectively. Lignin did not depress amino acid digestibility in general but specifically depressed methionine, histidine, isoleucine and threonine digestibility. Cellulose content did not affect amino acid digestibility but undesirable factors might be responsible.

• Asian-Australasian Journal of Animal Sciences
• /
• v.16 no.7
• /
• pp.979-982
• /
• 2003

Two rapeseed meal samples (Sample A, hybrid 5900 and sample B, double low rapeseed No.4) obtained from China and one Canola meal sample obtained from a local crushing plant in Canada were used to investigate the amino acid degradability of rapeseed/Canola meal in rumen and amino acid digestibility of ruminal incubation residues by precision-fed rooster bioassay. Results show that in ruminal incubation the degradation rate of non amino acid nitrogen in crude protein is higher than that for amino acid nitrogen in crude protein, the results also suggest that the degradation rate of amino acid nitrogen in Chinese rapeseed meal sample B was lower than that for Canadian Canola, but that in Chinese rapeseed meal sample A is much close to that for Canadian canola meal. For all amino acids the digestibility of the bypass or residual protein as measured by the precision-fed rooster bioassay tended to be lower for Chinese rapeseed meal sample A than for sample B or Canadian canola meal which had similar digestibility values. However following a calculation of total amino acid availability, involving the digestibility of amino acids in the rumen and rooster bioassay the results are less contradictory. Results indicated that in traditional roasting-expelling process, heat treatment, especially dry heat treatmeat could decrease amino acids degradability in rumen of rapeseed/canola meal, but also may decrease total availability of amino acids of rapeseed/canola meal.

• Asian-Australasian Journal of Animal Sciences
• /
• v.21 no.2
• /
• pp.232-236
• /
• 2008

This experiment was performed to investigate the effects of two energy levels and four lysine:digestible energy (DE) ratios on the apparent digestibility of nutrients in finishing pigs. The experiment was conducted using a $2{\times}4$ randomized complete block (RCB) design with three replicates. Twenty-four cross-bred finishing barrows ((Landrace${\times}$Yorkshire)${\times}$Duroc) with an average body weight of $64.2{\pm}0.69kg$ were assigned to one of eight treatments. Each barrow was placed in an individual metabolism crate and dietary treatment and water was provided ad libitum. Diets were designed to contain lysine:ME ratios of 1.5, 1.8, 2.1 and 2.4 g/Mcal at 3.35 and 3.6 Mcal/kg of diet in a $4{\times}2$ factorial arrangement. Dry matter (DM), ash, Ca and P digestibility were not affected by energy density or lysine:DE ratios. Crude fat digestibility increased as the energy density increased from 3.35 to 3.6 Mcal of DE/kg. Increasing the lysine:DE ratio also increased crude protein digestibility. There were no interactions between energy density and lysine:DE ratio in terms of nutrient digestibility. Nitrogen excretion via feces was not affected by energy density and lysine:DE ratio, while nitrogen excretion via urine was significantly affected by energy density and lysine:DE ratio. The apparent digestibility of all amino acids except for isoluecine, arginine and aspartic acid as well as average values of essential amino (EAA), non-essential amino acids (NEAA) and total amino acid digestibility (p>0.05) were not affected by energy density. The apparent digestibility of all amino acids except for leucine, proline, alanine and tyrosine, NEAA and total amino acid digestibility were significantly affected by lysine: DE ratio (p<0.05). Interactive effects of energy and lysine:DE ratio also significantly affected amino acid digestibility except for isoleucine, alanine, cystine, leucine, phenylalanine, glutamine and proline (p<0.05). In conclusion, these results suggest that maintaining the appropriate lysine:DE ratio becomes more important as the energy density of the diet increases. Consequently, increasing the lysine:DE ratio can result in increased crude protein digestibility and urinary nitrogen excretion, although apparent protein digestibility and nitrogen excretion were not affected by energy density Furthermore, increasing the lysine:DE ratio also increased the apparent digestibility of essential amino acids, except for leucine, regardless of energy density. The optimum lysine:DE ratio for maximum essential amino acid digestibility of the $64.2{\pm}0.69kg$ pig is approximately 2.4 g of lysine/Mcal of DE.

• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.10
• /
• pp.1507-1516
• /
• 2002

Meat and bone meal is a valuable protein and mineral source in diets of production animals and contributes to the protein, energy and mineral component of diets. The aim of the present study was to more accurately characterise the apparent ileal amino acid digestibility of meat and bone meals produced in New Zealand and evaluate routine in vitro assays used in practise to measure meat and bone meal quality. A total of 94 commercial meat and bone meals from 25 New Zealand rendering plants over a two and a half year period were analysed for proximates, gross energy, gross amino acid content (incl. hydroxyproline, hydroxylysine and lanthionine), apparent ileal amino acid digestibility, pepsin nitrogen digestibility, protein solubility and bone content. The mean crude protein content of the 94 meat and bone meal samples was 56.8% with a range of >35% units and a coefficient of variation of 9.8%. The mean crude fat and ash content were 10.0 and 28.4% respectively. These latter components showed a large range (16 and 43%, respectively) with coefficients of variation above 22%. Amino acid digestibility between samples was highly variable with lysine and sulphur amino acids digestibility ranging between 45.8-89.0 and 38.2-85.5%, respectively. Pearson correlation coefficients are presented between crude protein content and individual gross amino acids, crude protein content and individual digestible amino acid content, and pepsin N digestibility and individual digestible amino acid content. There was a significant relationship between the digestible amino acid nitrogen content and the crude protein content while pepsin nitrogen digestibility was not correlated to ileal amino acid nitrogen digestibility (r=-0.06). Meat meals with a high protein content had relatively low hydroxyproline and hydroxylysine levels something that was attributed to the levels of collagen from bone. The data indicated that lanthionine (formed upon heat treatment of cysteine with a hydroprotein) is not a good indicator of the heat treatment employed to meat and bone meals. Step-wise multiple regression equations to predict the apparent digestible content of amino acids from rapid in vitro assays are presented. The most selected variables included ash and crude fat content. In general the equations derived for the essential amino acids had a higher degrees of fit (R2) compared to the non-essential amino acids. The R2 for the essential amino acids ranged from 0.43 for histidine and 0.68 for leucine. These equations provide a means of more rapidly estimating the apparent ileal digestible amino acid content (protein quality) of meat and bone meal using standard analyses.

• Asian-Australasian Journal of Animal Sciences
• /
• v.19 no.7
• /
• pp.1040-1046
• /
• 2006

Studies were carried out with a repeated $4{\times}4$ Latin square design with eight cannulated pigs fed four experimental diets to investigate the effect of dietary fiber and starch sources on apparent ileal and fecal amino acid digestibility. Each period lasted 15 d, with diet acclimation from d 1 to 7, feces collection for 48 h on d 8 to 9 and ileal sample collection for 12 h on d 13 to 15. The four experimental diets consisted mainly of cooked rice with the addition of protein sources (CON), partial replacement of cooked rice with either potato starch (PS), sugar beet pulp (SBP) or wheat bran (WB). Chromic oxide was used as an indigestible marker. With the exception of histidine, lysine and tryptophan, no differences were observed in the apparent ileal digestibility of amino acids between diets. The inclusion of potato starch did not affect the ileal and fecal amino acid digestibility. In comparison with diet CON, a decreased (p<0.05) ileal digestibility of histidine was found in pigs fed diet SBP, while the ileal digestibilities of histidine, lysine and tryptophan were decreased (p<0.05) by the inclusion of wheat bran. Inclusion of fiber sources (sugar beet pulp and wheat bran) caused a reduction (p<0.05) in the fecal amino acid digestibility and the net disappearance of amino acids in the large intestine. Of the indispensable amino acids, there was a 'net synthesis' for methionine in the large intestine of pigs when diets were supplemented with dietary fiber. The decrease in fecal amino acid digestibility with the addition of dietary fiber indicates an increase in the synthesis of bacterial protein in the large intestine.

• Asian-Australasian Journal of Animal Sciences
• /
• v.23 no.5
• /
• pp.614-621
• /
• 2010

Increasing accuracy of broiler diet formulation based on amino acid digestibility in comparison to application of total amino acids could lead to more feed efficiency and productivity. This experiment was conducted for determination of sampling site (excreta and ileum) and recognition of the effects of a commercial enzyme ($Grind^{(R)}$ Danisco, Finland) on metabolizable energy, protein and amino acid digestibility of barley. This study was modulated by a marker in 21-day old Arbor Acres chickens. Corn-soybean meal was used as a control diet and, in the other two treatments, barley (at a level of 40%) with and without enzyme as the test ingredient were supplemented to the basal diet. Chromic oxide was included in all diets (0.5%) as an indigestible marker. Apparent metabolizable energy (AME), corrected by nitrogen (AMEn) and apparent digestibility of aspartic acid, glutamic acid, serine, glycine, alanine, tyrosine, valine and methionine were significantly (p<0.05) higher in feces than ileum. Protein digestibility of diet and barley was significantly (p<0.05) higher in the ileum than in feces. Apparent digestibility of tryptophan, proline, methionine, phenylalanine and lysine was increased significantly (p<0.05) by enzyme supplementation. In contrast, no response was observed in AME, AMEn, and protein digestibility of the diet and barley by enzyme supplementation. The results of this study have shown that AME and amino acid digestibility were increased in feces, in contrast an adverse effect was observed for protein digestibility of the diet and barley.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.6
• /
• pp.802-806
• /
• 2005

The objective of this study was to determine the effects of processing method and rapeseed variety on ruminal and intestinal protein digestibility of rapeseed meal in steers. Intestinal amino acid digestibility was assessed with an in situ ruminal incubation and precision-fed rooster bioassay. In this experiment one traditional rapeseed meal sample (sample A, prepress extraction) and three double low rapeseed meal samples (sample B, prepress extraction, sample C, screw press and sample D, low temperature press) were placed in polyester bags(8 cm${\times}$12 cm) and suspended in the ventral rumen of steers for 16 h. The residues of in situ incubations were intubated to roosters. Total excreta were collected for 48 h after incubation and then desiccated and amino acid concentrations were determined. Results showed that in ruminal incubation the degradation rate of amino acid and crude protein was higher for traditional rapeseed meal sample A than for double low rapeseed meal sample B, but was much lower than for double low sample C and D. In the group of double low rapeseed meal samples, sample D processed by low temperature press had the highest degradation rate of amino acids in the rumen. For all amino acids, the digestibility of the residual protein as measured by the precision-fed rooster bioassay tended to be lower for sample B than for sample A, which had the same processing method with sample B, and in the group of double low rapeseed meals, sample B had similar digestibility of amino acid in residual protein to sample D and higher than that of sample C. However, although the total amino acid availability involving the digestibility of amino acids in the rumen and rooster bioassay of double low rapeseed meal sample D (low temperature press) was higher than those of the other three samples by 7 to 9 percent, there were no significant differences. Results indicated that processing method markedly affected ruminal and post ruminal amino acid digestibility of rapeseed meal when the temperature exceeded 110$^{\circ}C$. Rapeseed meal that had a high content of fiber was not suitable for dry heat treatment at higher temperatures or the amino acids digestibility in rumen and total availability of amino acids could be reduced. Results also suggested the variety of rapeseed meal had no significant effect on the digestibility and availability of amino acids.

• Asian-Australasian Journal of Animal Sciences
• /
• v.11 no.2
• /
• pp.201-207
• /
• 1998

One growth trial and one digestibility trial were conducted to evaluate the nutritional value of HP300, a commercially processed soybean meal product for weanling pigs. Dried whey, fish meal and/or full fat extruded soybeans (FFES) as well as portions of soybean meal (SBM) were replaced with HP300 in weanling pig diets. The objectives were to investigate the effects of HP300 on growth performance, digestibility, ileal amino acid digestibility and blood amino acid concentration in weanling pigs. One hundred and twenty crossbred $(Duroc{\times}Beijing\;Black{\times}Landrace)$ pigs weaned at 28 days of age were used in the growth trial. The pigs were randomly allocated to five treatments, with three pens per treatment and eight pigs per pen. The trial duration was 28 days. The control (CTRL) diet contained no HP300; in treatments 2, 3 and 4, dried whey and fish meal were replaced by 3.0%, 7.5% and 10.5% HP300; in treatment 5, full fat extruded soybeans were replaced by 10.5% HP300 plus soybean oil to attain the same metabolic energy content as FFES. Five T-cannulated barrows were used in a digestibility trial with a $5{\times}5$ Latin square design to determine nitrogen retention and amino acid ileal digestibility of HP300 used alone or mixed with other ingredients. The results indicated that replacement of dried whey, fish meal, full fat extruded soybeans and a part of the soybean meal with HP300 in piglet diets improved average daily gain and feed conversion ratio (p < 0.05). There was a trend toward improved DM, crude protein and amino acid ileal digestibilities and improved protein and amino acid ileal digestibilities and improved protein net availability with the use of HP300 in swine diets.

• Asian-Australasian Journal of Animal Sciences
• /
• v.7 no.1
• /
• pp.113-117
• /
• 1994

The effect if heat treatment (autoclave) in amino acid digestibility of winged bean determined using intact cockerels had been investigated. The winged beans were autoclaved at $120^{\circ}C$ for 45 or 90 min, respectively, and the soybean were autoclaved for 45 min. The treated winged bean and soybean were fed to 3 intact cockerels, which had been previously starved for 24 h. Excreta were collected individually for 49 h. The amino acids contained in the diets and excreta were determined to measure the digestibility values. Apparent and true digestibilities of all amino acids except histidine of unheated winged bean were significantly (P < 0.05) lower than those of heated winged bean and soybean. Heat treatment significantly (p < 0.05) improved amino acid digestibility of winged bean, However, over heating (90 min if autoclaving) destroyed lysine, cystine and arginine of winged bean. The true digestibility values of all amino acids of winged bean heated for 90min were the same as those values of treated soybean. However, true digestibilities of glycine, alannine, phenylalanine and lysine of treated soybean were significantly (p < 0.05) higher than those of winged bean heated for 45 min.