• Title/Summary/Keyword: 3 ${\times}$ 3 Latin square design

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The Effects of Cellulose, Pectin and Starch on Standardized Ileal and Apparent Total Tract Amino Acid Digestibilities and Bacterial Contribution of Amino Acids in Feces of Growing Pigs

  • Ma, Q.G.;Metzler, B.U.;Eklund, M.;Ji, C.;Mosenthin, R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.6
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    • pp.873-882
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    • 2008
  • Eight ileally cannulated pigs (BW $35.9{\pm}0.9kg$) were randomly allotted according to a $4{\times}3$ Latin square design to determine the effects of cellulose, pectin and starch on standardized ileal digestibility (SID) and apparent total tract digestibility (ATTD) of crude protein (CP) and amino acids (AA) as well as on the bacterial AA contribution in feces. The pigs were fed the control diet (20.2% CP, % dry matter (DM)) or one of the three experimental diets in which 25% of the control diet was substituted by cellulose, starch or pectin. Due to this substitution, dietary CP levels were lower in the cellulose (15.5% CP, % DM), pectin (15.4% CP, % DM) and starch diet (15.2% CP, % DM). Following a 15-d adaptation period, feces were collected for 5 d and ileal digesta for a total of 24 h. Starch increased SID of CP, while cellulose and pectin had no significant effect on the digestibility of CP. Overall, starch supplementation resulted in higher (p<0.05) SID values of histidine, isoleucine, threonine, alanine, aspartic acid, cysteine, glycine and serine compared with cellulose, while pectin decreased (p<0.05) SID of valine and proline compared with the starch and control diet. Both cellulose and pectin reduced (p<0.05) the ATTD of CP and AA, while starch decreased (p<0.05) ATTD of phenylalanine, alanine, proline and serine compared with the control. With regard to bacterial AA composition of the fecal mixed bacterial mass (MBM), cellulose supplementation increased (p<0.05) its content of N and almost all AA, except for valine, while pectin caused higher contents of arginine, histidine and proline compared with the control (p<0.05). The bacterial contribution of arginine in feces was higher (p<0.05) in the cellulose treatment, while pectin reduced (p<0.05) the bacterial contribution of leucine, alanine, glutamic acid and proline in feces compared with the control. In conclusion, the effects of cellulose, starch and pectin on SID were rather small. Bacterial activity in the large intestine can only explain the reduced ATTD values for arginine in the cellulose treatment, but not for the other AA in the cellulose and pectin treatments, suggesting higher endogenous losses of these AA in the large intestine.

Measurement of Microbial Protein Supply in Murrah Buffaloes (Bubalus bubalis) Using Urinary Purine Derivatives Excretion and PDC Index

  • Dipu, M.T.;George, S.K.;Singh, P.;Verma, A.K.;Mehra, U.R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.3
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    • pp.347-355
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    • 2006
  • A study was conducted to predict the rumen microbial protein production based on urinary excretion of purine derivatives in buffaloes fed a diet of wheat straw and concentrate (40:60) at four fixed levels of feed intake. (95, 80, 60 and 40% of preliminary voluntary feed intake) following experimental protocol of IAEA (Phase I). The buffaloes were allocated according to a $4{\times}4$ latin square design. The urinary allantoin, uric acid, total PD excretion (mmol/d) in treatments L-95, L-80, L-60 and L-40 was 20.13, 16.00, 12.96 and 9.17; 1.88, 2.12, 2.11 and 2.15; 22.01, 18.12, 15.07 and 11.32, respectively and were significantly (p<0.05) different among treatments except for uric acid. The rate of PD excretion (mmol/d) was positively correlated with the digestible organic matter intake. Variations were observed in PD and creatinine concentration in spot samples collected at 6-hour interval. However, daily PD:Creatinine ratio (PDC index) appears to be a reasonably good predictor of microbial-N supply. The contribution of basal purine excretion to total excretion of purine derivatives (PD) was determined in pre-fasting period followed by a fasting period of 6 d (Phase II). Daily PD and creatinine excretion (mmol/kg $W^{0.75}$) during fasting averaged 0.117 and 0.456 respectively for buffaloes. The excretion rates of PD decreased significantly (p<0.01) during fasting compare to pre-fasting period, the urinary creatinine excretion remained almost similar. Except for creatinine, plasma concentration of target parameters significantly (p<0.01) declined during fasting. Likewise, glomerular filtration rate (GFR) and renal clearance of allantoin and uric acid also decreased. Based on the PD excretion rates during fasting and at different levels of feed intake obtained in this study, a relationship between daily urinary PD excretion (Y-mmol) and microbial purine absorption (X-mmol) was developed for buffaloes as Y = 0.74X+0.117 kg $W^{0.75}$. The microbial N supply (g/kg DOMI) remained statistically similar irrespective of dietary treatment. The results showed that excretion of urinary purine derivatives is positively correlated with the levels of feed intake in Murrah buffaloes and thus, estimation of urinary purine derivatives and PDC index could be used to determine microbial nitrogen supply when there is large variation in level of feed intake.

Effects of Alfalfa and Brown Mid-rib Corn Silage and Level of Forage Neutral Detergent Fiber on Animal Performance of Lactating Cows in Michigan

  • Min, Doo-Hong;Bucholtz, Herb;Naasz, Paul
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.3
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    • pp.373-377
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    • 2007
  • Alfalfa silage and corn silage are the major dairy feeds in most dairy operations in Michigan, USA. In recent years, the need to improve digestible fiber and dry matter intake of forages to meet the nutrient requirements of high yielding dairy cows and the willingness to plant corn specifically for silage has led plant breeders to focus on the brown mid-rib (BMR) trait. The objective of this study was to investigate the effect of different ratio of alfalfa to BMR corn silage and ration level of forage neutral detergent fiber (NDF) on animal performance of lactating cows in the Upper Peninsula of Michigan. This study was conducted at the Upper Peninsula Experiment Station of Michigan State University in Chatham, Michigan, USA. Two different ratios of forage type (high alfalfa silage/low BMR corn silage, AS, and high BMR corn silage/low alfalfa silage, BMRCS) and two different dietary NDF contents (27% NDF, 27 = low forage/high grain feeding, and 33% NDF, 33 = high forage/low grain feeding) were used. The experimental design was a $4{\times}4$ Latin Square with 20 milking cows (12 multiparous and 8 primiparous). This trial had four 21-day periods with 14 d adaptation and 7 d data collection. Milk yield and body condition score (BCS) on the AS-27, BMRCS-27 and BMRCS-33 treatments were significantly (p<0.05) higher than on the AS-33 treatment. Dry matter intake of the AS-27 and BMRCS-27 treatments was significantly (p<0.05) higher than for the AS-33 and BMRCS-33 treatments. Milk urea nitrogen (MUN) on the AS-33 treatment was significantly (p<0.05) higher than on the other diet treatments. A key finding of this study was that the BMRCS-33 (higher amounts of brown mid-rib corn silage than alfalfa silage, high forage and low grain feeding diet at 33% NDF) led to the equal highest milk production whilst having the equal lowest dry matter intake. This study demonstrated that the diet with higher ratio of highly digestible NDF forage such as brown mid-rib corn silage to alfalfa silage could lower grain feeding in the ration.

Rumen Fermentation and Performance of Lactating Dairy Cows Affected by Physical Forms and Urea Treatment of Rice Straw

  • Gunun, P.;Wanapat, M.;Anantasook, N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.9
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    • pp.1295-1303
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    • 2013
  • The aim of this study was to determine the effect of different physical forms and urea treatment of rice straw on feed intake, rumen fermentation, and milk production. Four, multiparous Holstein crossbred dairy cows in mid-lactation with initial body weight (BW) of $409{\pm}20kg$ were randomly assigned according to a $4{\times}4$ Latin square design to receive four dietary treatments. The dietary treatments were as follows: untreated, long form rice straw (LRS), urea-treated (5%), long form rice straw (5% ULRS), urea-treated (2.5%), long form rice straw (2.5% ULRS) and urea-treated (2.5%), chopped (4 cm) rice straw (2.5% UCRS). Cows were fed with concentrate diets at a ratio of concentrate to milk yield of 1:2 and rice straw was fed ad libitum. The findings revealed significant improvements in total DM intake and digestibility by using long and short forms of urea-treated rice straw (p<0.05). Ruminal pH was not altered among all treatments (p>0.05), whereas ruminal $NH_3$-N, BUN and MUN were found to be increased (p<0.01) by urea-treated rice straw as compared with untreated rice straw. Volatile fatty acids (VFAs) concentrations especially those of acetic acid were decreased (p<0.05) and those of propionic acid were increased (p<0.05), thus acetic acid:propionic acid was subsequently lowered (p<0.05) in cows fed with long or short forms of urea-treated rice straw. The 2.5% ULRS and 2.5% UCRS had greater microbial protein synthesis and was greatest when cows were fed with 5% ULRS. The urea-treated rice straw fed groups had increased milk yield (p<0.05), while lower feed cost and greater economic return was in the 2.5% ULRS and 2.5% UCRS (p<0.01). From these results, it could be concluded that 2.5% ULRS could replace 5% ULRS used as a roughage source to maintain feed intake, rumen fermentation, efficiency of microbial protein synthesis, milk production and economical return in mid-lactating dairy cows.

Effects of Synchronization of Energy and Nitrogen Release in the Rumen on the Starch Disappearance in the Gastrointestinal Tract and Growth Performance of Hanwoo Steers

  • Li, Dong-Hua;Oh, Young-Kyoon;Lee, Sang-Rak;Choi, Seong-Ho;Un, Ok-Ji;Seol, Yong-Joo;Nho, Whan-Gook;Moon, Sang-Ho;Kim, Kyoung-Hoon
    • Journal of Animal Science and Technology
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    • v.53 no.6
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    • pp.533-540
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    • 2011
  • The objectives of experiments were to compare directly the effects of synchrony of slowly fermented (corn and corn gluten meal; C-CGM) and of rapidly fermented ingredients (barley and soybean meal; B-SBM) in the rumen on starch disappearances in gastrointestinal tracts (Experiment 1) and growth performance (Experiment 2) of Hanwoo steers in the feedlot barn. In experiment 1, four Hanwoo steers ($288{\pm}21$ kg) fitted with ruminal and "T" shaped duodenal cannula were placed in one pen with Calan gate and assigned randomly to a duplicate $2{\times}2$ Latin square design. In experiment 2, eight intact Hanwoo steers ($311{\pm}8$ kg) were assigned randomly to one of two pens with Calan gate to evaluate the effect of the same diets as like in experiment 1 on growth performance. There were no differences in ruminal pH, ammonia and total VFA concentrations between treatments. Percentage of apparent ruminal starch disappearance was 33.3% unit lower (p<0.05) for steers fed C-CGM than for steers fed B-SBM diets and this difference resulted in 268% higher (p<0.05) in duodenal starch flows for steers fed C-CGM diet than for steers fed B-SMB diet. There was significant increase (p<0.05) in quantity (927 vs. 400 g/d) of corn starch digested post-ruminally compared to barley starch. However, percentage of starch apparently digested post-ruminally was 8% higher (p=0.1) in steers fed fast synchrony diet with B-SBM than in steers fed slow synchrony diets with C-CGM. The differences of percentage and amount of starch apparently digested post-ruminally between C-CGM and B-SBM diets did not affect rice straw DM intake, average daily gain (ADG) and feed efficiency. In conclusion, there is some uncertainty in regards to the relationship between site of starch digestion and DM intake, ADG, and feed efficiency in this study.

Effect of Dietary Concentrate:forage Ratios and Undegraded Dietary Protein on Nitrogen Balance and Urinary Excretion of Purine Derivatives in Dorper×thin-tailed Han Crossbred Lambs

  • Ma, Tao;Deng, Kai-Dong;Tu, Yan;Jiang, Cheng-Gang;Zhang, Nai-Feng;Li, Yan-Ling;Si, Bing-Wen;Lou, Can;Diao, Qi-Yu
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.2
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    • pp.161-168
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    • 2014
  • This study aimed to investigate dietary concentrate:forage ratios (C:F) and undegraded dietary protein (UDP) on nitrogen balance and urinary excretion of purine derivatives (PD) in lambs. Four Dorper${\times}$thin-tailed Han crossbred castrated lambs with $62.3{\pm}1.9$ kg body weight at 10 months of age were randomly assigned to four dietary treatments in a $2{\times}2$ factorial arrangement of two levels of C:F (40:60 and 60:40) and two levels of UDP (35% and 50% of CP), according to a complete $4{\times}4$ Latin-square design. Each experimental period lasted for 19 d. After a 7-d adaptation period, lambs were moved into individual metabolism crates for 12 d including 7 d of adaption and 5 d of metabolism trial. During the metabolism trial, total urine was collected for 24 h and spot urine samples were also collected at different times. Urinary PD was measured using a colorimetric method and creatinine was measured using an automated analyzer. Intake of dry matter (DM) (p<0.01) and organic matter (OM) (p<0.01) increased as the level of UDP decreased. Fecal N was not affected by dietary treatment (p>0.05) while urinary N increased as the level of UDP decreased (p<0.05), but decreased as dietary C:F increased (p<0.05). Nitrogen retention increased as dietary C:F increased (p<0.05). As dietary C:F increased, urinary excretion of PD increased (p<0.05), but was not affected by dietary UDP (p>0.05) or interaction between dietary treatments (p>0.05). Daily excretion of creatinine was not affected by dietary treatments (p<0.05), with an average value of $0.334{\times}0.005$ mmol/kg $BW^{0.75}$. A linear correlation was found between total PD excretion and PDC index ($R^2$ = 0.93). Concentrations of creatinine and PDC index in spot urine were unaffected by sampling time (p>0.05) and a good correlation was found between the PDC index (average value of three times) of spot urine and daily excretion of PD ($R^2$ = 0.88). These results suggest that for animals fed ad libitum, the PDC index in spot urine is effective to predict daily excretion of PD. In order to improve the accuracy of the spot sampling technique, an appropriate lag phase between the time of feeding and sampling should be determined so that the sampling time can coincide with the peak concentration of PD in the urine.

Comparison of Methane Production in Korean Native Cattle (Hanwoo) Fed Different Grain Sources (곡류 사료원별 육성기 한우 장내발효에 의한 메탄가스 배출량 비교)

  • Seol, Yong-Joo;Kim, Kyoung-Hoon;Baek, Youl-Chang;Lee, Sang-Cheol;Ok, Ji-Woun;Lee, Kang-Yeon;Hong, Seong-Koo;Park, Kyu-Hyun;Choi, Chang-Weon;Lee, Sung-Sil;Oh, Young-Kyoon
    • Journal of Animal Science and Technology
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    • v.53 no.2
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    • pp.161-169
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    • 2011
  • Methane production during anaerobic fermentation in the rumen represents an energy loss to the host animal and induces emissions of greenhouse gases in the environment. Our study focused on comparison in methane production from growing Korean native steers fed different grain sources. Six Hanwoo steers (BW = $180.6{\pm}3.1$ kg) were fed, on a DM basis (TDN 2.80 kg), 40% timothy and 60% barley concentrate (Barley) or corn concentrate (Corn), respectively, based on the Korean Feeding Standards. Each period lasted 18 days including a 14-day adaptation and a 4-day measuring times. The steers were in the head hood chamber system (one cattle per chamber) during each measuring time to measure heat and methane production per day. Different grain sources did not affect digestibilities of dry matter, crude protein, crude fiber, crude fat, NDF, ADF and nitrogen-free extract. The mean methane concentrations per day were 202.0 and 177.1 ppm for Barley and Corn, respectively. Methane emission averaged 86.8 and 77.7 g/day for Barley and Corn, respectively. Methane emission factor by maintenance energy requirement for the growing steers fed barley based concentrate was higher than the steers fed corn based concentrate (Barley vs. Corn, 31.7 kg $CH_4\;head^{-1}\;yr^{-1}$ vs. 28.4 kg $CH_4\;head^{-1}\;yr^{-1}$). Thus, methane conversion rate was 0.065 (6.5%) and 0.055 (5.5%) for Barley and Corn, respectively.

Effects of Single Cell Protein Replacing Fish Meal in Diet on Growth Performance, Nutrient Digestibility and Intestinal Morphology in Weaned Pigs

  • Zhang, H.Y.;Piao, X.S.;Li, P.;Yi, J.Q.;Zhang, Q.;Li, Q.Y.;Liu, J.D.;Wang, G.Q.
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.9
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    • pp.1320-1328
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    • 2013
  • Three experiments were conducted to evaluate the ME value, standardized ileal digestibility (SID) of amino acids (AA) of fish meal, and the effects of single cell protein (Prosin and Protide) replacing fish meal in diet on growth performance, nutrient digestibility and intestinal morphology in weaned piglets. In Exp. 1, twenty-four barrows with initial BW of $30.8{\times}2.6kg$ were allotted to one of four dietary treatments. Diet 1 contained corn as the only energy source. The other three diets replaced 20% of the corn in diet 1 with one of the three protein feeds (fish meal, Prosin and Protide), and the DE and ME contents were determined by difference. In Exp. 2, eight barrows (initial BW of $25.6{\pm}3.2kg$) were fitted with ileal T-cannulas and allotted to a replicated $4{\times}4$ Latin square design. Three cornstarch-based diets were formulated using each of the protein feeds as the sole source of AA. A nitrogen-free diet was also formulated to measure endogenous losses of AA. In Exp. 3, one hundred and eighty piglets (initial BW of $7.95{\pm}1.59kg$) weaned at $28{\times}2d$ were blocked by weight and assigned to one of five treatments for a 28-d growth performance study, each treatment was fed to six pens with six pigs (three barrows and three gilts) per pen. The five treatments consisted of the control group (CON), which was a corn-soybean meal diet containing 5% fish meal, and the other four treatments, which replaced a set amount of fish meal with either Prosin (2.5% or 5%) or Protide (2.5% or 5%). The diets were formulated to provide same nutrient levels. The results showed that on a DM basis, both of the DE and ME contents were lower in Prosin and Protide than that of fish meal (p<0.05). The SID of CP and all essential AA were greater in fish meal than in Prosin and Protide (p<0.05). The pigs fed CON diet had greater weight gain and lower feed conversion rate (FCR) than pigs fed 5% Prosin and 5% Protide diets (p<0.05). The digestibility of CP was greater in pigs fed CON, 2.5% Prosin and 2.5% Protide diets than the pigs fed 5% Prosin and 5% Protide diets (p<0.05). Villus height in jejunum and ileum, and villus height to crypt depth ratio in the jejunum were higher (p<0.05) in pigs fed CON, 2.5% Prosin and 2.5% Protide diets compared with the 5% Prosin and 5% Protide diets. Pigs fed CON diet had greater villus height to crypt depth ratio in the ileum than the pigs fed 5% Prosin and 5% Protide diets (p<0.05). In conclusion, although Prosin and Protide contained lower ME content and SID of AA than fish meal, Prosin and Protide replacing 50% of fish meal in diet with identical nutrient levels could obtain similar performance, nutrient digestibility and intestinal morphology in weaned pigs.

Effect of Microbial Phytase on Performance, Nutrient Absorption and Excretion in Weaned Pigs and Apparent Ileal Nutrient Digestibility in Growing Pigs

  • Zeng, Z.K.;Piao, X.S.;Wang, D.;Li, P.F.;Xue, L.F.;Salmon, Lorraine;Zhang, H.Y.;Han, X.;Liu, L.
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.8
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    • pp.1164-1172
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    • 2011
  • Two experiments were conducted to evaluate the efficacy of Trichoderma reesei derived phytase for pigs fed diets with fixed calcium to total phosphorus ratios (1.5:1). In Exp. 1, 280 weaned pigs (initial BW of $10.32{\pm}1.94$ kg) were allocated to one of five dietary treatments on the basis of weight and gender in a randomized complete block design. Treatments were the low phosphorus (0.6% Ca, 0.4% total P and 0.23% available P) diets supplemented with 0, 250, 1,000, or 2,000 FTU phytase/kg of diet and a positive control diet (PC; 0.85% Ca, 0.58% total P and 0.37% available P). The treatments were applied to seven pens with eight pigs per pen, half male and half female. In Exp. 2, six barrows fitted with ileal T-cannula (initial BW = $35.1{\pm}1.6$ kg) were assigned to three dietary treatments with a double $3{\times}3$ Latin square design. The dietary treatments were the low-phosphorus diet (0.53% Ca, 0.34% total P and 0.14% available P), the low phosphorus diet plus 1,000 FTU phytase/kg and a positive control diet (0.77% Ca, 0.50% total P and 0.30% available P). In Exp. 1, there were linear increases (p<0.01) in weight gain, phosphorus absorption, bone strength, calcium and phosphorus content of fat-free dried bone and plasma phosphorus concentrations with increasing dose rate of phytase. The performance of pigs fed the diets with 250, 1,000, or 2,000 FTU of phytase/kg did not differ from pigs fed the PC diet. Pigs fed diets with 1,000 or 2,000 FTU of phytase/kg did not differ from pigs fed the PC diet in bone characteristics. The apparent digestibility of dry matter, crude protein, ash and energy was not affected by dietary treatment. However, pigs fed the PC diet excreted more fecal phosphorus (g/d, p<0.01) and fecal phosphorus per BW gain (g/kg) than pigs fed the diets with phytase. Phytase linearly decreased (p<0.01) fecal phosphorus excreted per BW gain (g/kg), plasma calcium concentration as well as plasma and bone alkaline phosphatase activity. In Exp. 2, phytase supplementation in the low-P diet increased (p<0.05) the apparent ileal digestibility (AID) of Ca, P, leucine, lysine, phenylalanine, alanine and cysteine, tended to AID of crude protein, isoleucine, threonine, asparagine and serine. In conclusion, the novel phytase originated from Trichoderma reesei is effective in releasing Ca, P, and amino acids from corn soy based diet for pigs.

Effects of Level and Degradability of Dietary Protein on Ruminal Fermentation and Concentrations of Soluble Non-ammonia Nitrogen in Ruminal and Omasal Digesta of Hanwoo Steers

  • Oh, Young-Kyoon;Kim, Jeong-Hoon;Kim, Kyoung-Hoon;Choi, Chang-Won;Kang, Su-Won;Nam, In-Sik;Kim, Do-Hyung;Song, Man-Kang;Kim, Chang-Won;Park, Keun-Kyu
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.3
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    • pp.392-403
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    • 2008
  • Four ruminally fistulated Hanwoo steers were used to determine the effects of level and degradability of dietary protein on ruminal fermentation, blood metabolites and concentration of soluble non-ammonia nitrogen (SNAN) in ruminal (RD) and omasal digesta (OD). Experiments were conducted in a $4{\times}4$ Latin square design with a $2{\times}2$ factorial arrangement of treatments. Factors were protein supplements with two ruminal crude protein (CP) degradabilities, corn gluten meal (CGM) that was low in degradability (rumen-degraded protein (RDP), 23.4% CP) or soybean meal (SBM) that was high in degradability (RDP, 62.1% CP), and two feeding levels of CP (12.2 or 15.9% dry matter). Ruminal fermentation rates and plasma metabolite concentrations were determined from the RD collected at 2-h intervals and from the blood taken by jugular puncture, respectively. The SNAN fractions (free amino acid, peptide and soluble protein) in RD and OD collected at 2-h intervals were assessed by ninhydrin assay. Mean ruminal ammonia concentrations were 40.5, 74.8, 103.4 and 127.0 mg/L for low CGM, high CGM, low SBM and high SBM, respectively, with statistically significant differences (p<0.01 for CP level and p<0.001 for CP degradability). Blood urea nitrogen concentrations were increased by high CP level (p<0.001) but unaffected by CP degradability. There was a significant (p<0.05) interaction between level and degradability of CP on blood albumin concentrations. Albumin was decreased to a greater extent by increasing degradability of low CP diets (0.26 g/dl) compared with high CP diets (0.02 g/dl). Concentrations of each SNAN fraction in RD (p<0.01) and OD (p<0.05) for high CP diets were higher than those for low CP diets, except for peptides but concentrations of the sum of peptide and free amino acid in RD and OD were significantly higher (p<0.05) for high CP diets than for low CP diets. Soybean meal diets increased free amino acid and peptide concentrations in both RD (p<0.01) and OD (p<0.05) compared to CGM diets. High level and greater degradability of CP increased (p<0.001) mean concentrations of total SNAN in RD and OD. These results suggest that RDP contents, increased by higher level and degradability of dietary protein, may increase release of free amino acids, peptides and soluble proteins in the rumen and omasum from ruminal degradation and solubilization of dietary proteins. Because SNAN in OD indicates the terminal product of ruminal metabolism, increasing CP level and degradability appears to increase the amount of intestine-available nitrogen in the liquid phase.