Search

This article aims to review recent progress and update on utilization of exogenous fibrolytic enzymes in fiber fermentation, degradation, and digestions and nutritive and anti-nutritional characteristics of whole legume faba bean and its silage. The study focused on strategies to improve the utilization and bioavailability of fiber through pre-treating exogenous fibrolytic enzymes. The review includes features of nutrition and anti-nutritional factors and environment impact, forage fiber fermentation, degradation and digestion, legume bean in various diets, use of exogenous enzyme and factor affecting enzyme action in fiber digestion as well as exogenous enzyme response. This review also provides very recent research on effects of fibrolytic enzyme on rumen degradation characteristics of dry matter and fiber of whole plant faba bean silage and effect of exogenous fibrolytic enzyme derived from trichoderma reesei on lactational performance, feeding behavior, rumen fermentation and nutrient digestibility in dairy cows fed whole plant faba bean silage-based diet. This study provides an insight on nutritive and anti-nutritive characteristics of whole legume bean and its plant silage and utilization of exogenous fibrolytic enzymes in fiber fermentation, degradation, and digestions. [ABSTRACT FROM AUTHOR]

The effects of a Nutritional Packet offered to beef steers during the final 64 d of the feedlot-finishing phase on growth performance, carcass characteristics, nutrient digestibility, and feeding behavior were evaluated. Angus-crossbred steers (N = 120; initial body weight = 544 ± 52 kg) were assigned to 30 pens (4 steers per pen; 15 pens per treatment) in a randomized complete block design where pen was the experimental unit. A steam-flaked corn-based finishing diet was offered to ad libitum, and the treatments were as follows: 1) control and 2) 30 g per steer-daily (dry matter basis) of the Nutritional Packet. The Nutritional Packet was formulated to provide 1.7 × 1010 CFU per steer-daily of Saccharomyces cerevisiae, 162 mg per steer-daily of vitamin C; 400 mg per steer-daily of vitamin B1; 2.4 g per steer-daily of NaCl, and 2.4 g per steer-daily of KCl. Data were analyzed using the GLIMMIX procedure of SAS with the fixed effect of treatment and the random effect of block. The average daily gain (P = 0.89), dry matter intake (P = 0.57), and gain efficiency (P = 0.82) were not affected by the inclusion of the Nutritional Packet. Digestibility of dry and organic matter, and neutral and acid detergent fiber increased (P ≤ 0.02) for steers offered the Nutritional Packet, while a trend for the same response was observed for hemicellulose (P = 0.08). The 12th rib backfat thickness increased (P = 0.02) for carcasses of steers offered the Nutritional Packet, followed by a greater (P = 0.03) calculated yield grade, whereas other carcass traits were not affected (P ≥ 0.32). While the steers under the control diet decreased behavior activities on day 63, a consistent pattern of feeding behavior measurements (activity min/d and min/kg of dry and organic matter, fiber fractions, and digestible nutrients) were observed for steers consuming the Nutritional Packet during both feeding behavior assessment periods (treatment × period interactions, P ≤ 0.03). Overall time (min/d) spent on rumination, drinking, active, chewing, and resting were not affected (P ≥ 0.28) by treatments. The Nutritional Packet offered to steers during the final 64 d on feed induced an improvement in apparent digestibility of nutrients and carcass fat deposition, without affecting growth performance or other carcass quality indices. Such effects associated with the more consistent feeding behavior of steers receiving the Nutritional Packet may warrant a shorter time on feed during the final portion of the finishing phase. [ABSTRACT FROM AUTHOR]

Treats are important contributors to the economics of the U.S. pet product industry. Not only do pet owners use them to build an emotional bond or interact with their pets, but treats also can deliver functional or health benefits. The objective of this study was to evaluate the digestion and safety of selected commercial treats by measuring their in vitro dry matter disappearance (DMD) using the modified in vitro method of Boisen and Eggum, which was developed to simulate in vivo digestibility of nonruminant animals. Twenty-five commercial treats were classified into six categories based on their appearance, size, and functionality. These categories included biscuit, chew, dental, meat product, rawhide, and cat treat. Each commercial product was analyzed in triplicate and in vitro DMD was calculated after enzymatic digestion and incubation. A wide variation in DMD was observed among and within different treat categories in both gastric and gastric + small intestinal phases of digestion. For the gastric phase, DMD ranged from 8.40% to 92.20%, whereas intestinal phase digestion had a DMD range of 35.10–100% (P < 0.05). In general, treats from meat products, dental, chew, biscuit, and cat treat categories had a high DMD (>85%) after the intestinal phase, whereas DMD of rawhide treats varied from 35.10% to 95.70%. Principal component analysis, in addition, has visually shown that rawhide treats displayed the largest portion of variation from the other treats. A low DMD at gastric phase is a concern because it may pose a risk for gastrointestinal blockage and intolerance, particularly for treats of large size that remained intact during this phase. In vitro DMD results can be used as a potential predictor of in vivo digestibility, facilitate recommendations about pet treat safety for professionals and manufacturers in the pet industry, and assist pet owners in the treat selection process and with treat purchasing decisions. [ABSTRACT FROM AUTHOR]

BACKGROUND The effect of the inclusion of sunflower oil (SF) and quebracho tannin (QT) in a sheep diet was evaluated. Nutrient digestibility and nitrogen (N) utilization, as well as in vitro ruminal degradation kinetics, were evaluated at three levels [0, 20 and 40 g kg−1 of diet dry matter] of SF and QT in a 32 arrangement. The treatments were 0 (control); 20 and 40 g of QT and/or SF kg−1 of the diet. Four intact male sheep (45 ± 1.3 kg) for each treatment were used in the digestibility trial and kept individually in metabolic cages. RESULTS: Nutrient digestibility and N balance were not affected by SF. However, QT at 40 g kg−1 of dry matter decreased (P < 0.05) nutrient digestibility and also increased the proportion of absorbed N. Both SF and QT reduced (P < 0.05) the slowly degraded fraction and rate for organic matter and N. Even though the QT had a negative (P < 0.05) effect on nutrient digestibility, this effect was mild (P > 0.05) when SF was included in the QT‐added diets. Moreover, an interaction (P < 0.05) of SF × QT was observed on the synchronization index as an indicator of the efficiency of rumen microbial protein synthesis. CONCLUSION: Supplementation of either SF or QT to sheep diets reduced ruminal organic matter and N degradability, reflecting the compensatory digestion in the post‐ruminal track for organic matter feed utilization. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Background: There is a comprehensive understanding of the role of dietary fiber as a nutrient and its function during digestion in cattle. On the other hand, the role of fiber digestion in goats has not received similar attention. Objective: To evaluate the effects of different ratios of forage neutral detergent fiber (fNDF) and non-fibrous carbohydrates (NFC) on ruminal fermentation products, and in vitro neutral detergent fiber (NDF) digestibility in goats. Methods: A 3 × 5 factorial arrangement in a completely randomized design with three fNDF levels (100, 190, and 290 g/kg) and five NFC levels (350, 400, 450, 500, and 550 g/kg) was used. The experiment was performed in vitro. Two ruminally fistulated goats were used as rumen liquid donors. Results: The ratios between fNDF and NFC affected all ruminal parameters (p<0.05). Increasing NFC levels in diets containing 100 and 290 g/kg fNDF resulted in linear increase (p<0.05) in ammonia concentration after 48 h fermentation. There was no adjustment of linear models (p>0.05) for pH values. Total volatile fatty acids (VFA) and their individual molar proportions were affected (p<0.05) at all fNDF and NFC levels. The NDF digestibility was not affected (p>0.05) by fNDF or NFC levels, except for diets containing 290 g/kg fNDF, which were fit to a quadratic model (p<0.05). Conclusion: The relationship between fNDF and NFC concentrations affect the fermentation end products and in vitro NDF digestibility. NFC plays a more consistent role than fNDF in the ruminal microbial ecosystem of goats during in vitro fermentation. [ABSTRACT FROM AUTHOR]

Apparent total-tract digestibility data from 3 published studies with calves from 0 to 4 mo of age were used to evaluate National Research Council (2001) estimates of metabolizable energy (ME) in calf starters (CS). Calves (n = 83) or pens of calves (n = 24) were used in model development. In each study, 48 Holstein bull calves (2 to 3 d of age at initiation of each study) were fed varying amounts of milk replacer with CS and water for ad libitum consumption. Calf starters varied in nutrient content and form (pelleted, texturized, or mixed with 5% grass hay and fed as a total mixed ration). Apparent total-tract digestibility was measured at various ages from 3 to 16 wk. Feed and feces were collected from 20 calves per trial during 5-d collection periods during the first 56 d of each trial. In 2 studies, calves were grouped in pens (4 calves/pen) for a second 56-d measurement period. Fecal collections were repeated occasionally during the second period. Totaltract digestibilities (n = 207) of neutral detergent fiber, nonfiber carbohydrates, crude protein, and fat were used to calculate digestible energy (DE) and ME in CS using equations from the 2001 Dairy National Research Council. Three modeling approaches were constructed to evaluate changing digestion of nutrients, DE, and ME in CS, including linear mixed models, broken-line regression, and exponential models. Linear mixed models provided best model fit statistics for digestion of crude protein, ether extract, neutral detergent fiber, and ME. Exponential models were optimal for digestion of dry matter and nonfiber carbohydrates. Linear mixed models were selected for evaluation of effects of intake on changing nutrient digestion from CS and amount of DE and ME available at various ages. [ABSTRACT FROM AUTHOR]

Tea processing includes several stages and in three of them namely drying, fiber-mat and screening some of the product is wasted. In this study, 25 percent of the tea processing plants in Iran were selected. Three samples were taken from each plant and analyzed for chemical composition and in vitro and in vivo digestibility and voluntary feed intake. Results showed that crude protein (CP) content of different tea by-products including drying, fiber-mat and screening were 198, 193 and 194 g/kg dry matter (DM), respectively, without significant difference among them. Concentration of ash were 64.0, 62.0 and 56.0 g/kg DM for drying, fiber-mat and screening respectively which was significantly (P<0.05) the lowest in Screening. The content of K, Ca, P, Mg and Na were 16.2, 4.2, 2.5, 2.2 and 0.73 g/kg DM, respectively, without significant difference among the samples. The mean values for in vitro digestibility coefficient of DM, organic matter (OM), OM/DM and gross energy of the tea wastes were 0.48, 0.44, 0.42 and 0.42, respectively. Inclusion of tea waste in the diet significantly (P<0.05) reduced in vivo digestibility coefficient of CP and neutral detergent fiber (NDF). The digestible energy was 10.0 MJ/kg which were not significantly different among the three types of tea waste. Inclusion of 80 g/kg DM tea waste in the diet significantly (P<0.05) reduced voluntary feed intake. Tea waste can be included in the diet of ruminants but its level should be limited due to presence of anti-nutritional factors. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of two total mixed ration (TMR) silages (low and high rumen undegradable protein; RUP) on digestibility, blood parameters, and performance in pregnant beef cows. Thirty-three mid-gestation (~130 d of gestation) Tabapua beef cows were randomly assigned to 1 of 2 treatments: 1) a TMR silage containing Brachiaria grass, soybean hulls, urea, and mineral mix (low RUP; n = 16) or 2) a TMR silage containing Brachiaria grass, DDG, and mineral mix (high RUP; n = 17). The concentration of A1 fraction was, on average, 12.9% and 34.0% of N in low and high RUP silages, respectively. A preservative with a blend of organic acids, surfactants, and activated propionates was applied in both silages. Pressed bag silos were used to conserve silages for 7 wk. Cows were housed in individual pens for 100 d. During a 4-d digestion period (at 50 d of housing), fecal samples were collected for measurement of nutrient digestibility using undigested neutral detergent fiber as a marker. Blood parameters were collected at the last day of housing. Statistical analysis of experimental data was performed using the GLM procedure of SAS 9.4. Diet, calf sex (male or female), and interactions between these factors were considered fixed effects. No differences were obtained for initial BW. High RUP diet showed greater final BW (P = 0.0004) and ADG (P = 0.0003). Cows fed high RUP gained 50 g/d, while cows fed low RUP diet lost 445 g/d. Dry matter intake was greater by 23% (P < 0.0001) in cows consuming high RUP silage. Dry matter, CP, and NDF digestibility did not differ between treatments. Regarding blood parameters, no differences were observed for glucose at 0 h and 4 h post-feeding. Plasma urea at 0 h post-feeding was greater in cows fed low RUP silage (P = 0.0003). However, no differences were observed for plasma urea at 4 h post-feeding. The plasma concentrations of non-esterified fatty acids (P = 0.017) and beta-hydroxy-butyric acid (P = 0.002) were greater in cows consuming low RUP diet. Overall, feeding pregnant cows during mid-gestation with TMR silage containing high RUP promotes greater performance. [ABSTRACT FROM AUTHOR]

This study compares in situ, in vitro (DaisyII and gas production) and in vivo techniques to estimate the degradation of dry matter (DM), organic matter (OM), and N of sorghum grain. We used whole dried sorghum (WDS), dry cracked sorghum (DCS), the reconstituted whole sorghum silage (WSS) and reconstituted cracked sorghum silage (CSS). The residues obtained from the ruminal digestion in vitro (DaisyII) and in situ were analysed for their intestinal digestion (pepsin-pancreatin). OM was similar (981.32 ± 0.52) in all treatments, WSS showed the highest (P < .001) crude protein (CP) concentration compared with the other treatments, whereas CSS showed the highest amount of starch (P < .001) compared to other treatments. The apparent degraded substrate (ADS) was higher (P < .038) for whole sorghums, rumen degradable protein (RDP) was higher for WDS and WSS (P = .003), while protein digestible in the intestine (PDI) was higher for sorghums silage (P < .001) compared with dry sorghums. ADS was higher (P < .022) using the in sacco technique compared with the other methods, while for the RDP and PDI methods in sacco and in vitro (Daisy) showed the better degradation compared with in vivo. The reconstituted ensiling sorghum grains had a favourable response in the availability of nutrients, compared with dried sorghums. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study was conducted to determine the adequate dietary CP level for growing wethers by investigating the effect of dietary CP level on dry matter intake, apparent digestibility, and protein balance inKorean native goats. Each growing wether was fed three diets that were formulated to contain low (13%, T1), medium (15%, T2), and high (18%, T3) levels of CP based on dry matter. Dietary protein levels affected the apparent digestibility of CP, CP intake (CPI), urinary CP, digestible CP, and CP efficiency (p<0.05). The apparent CP digestibility increased linearly as dietary CP increased (T1=73.03%, T2=76.49%, T3=80.66%; p<0.05). The CPI and digestible CP for T3 (129.92g/d, 104.93g/d) were also higher (p<0.05) than those for T1 (90.39g/d, 65.68g/d), in addition, urinary emission for T3 (55.23g/d) was higher (p<0.05) than that for T2 (27.11g/d). CP utilization efficiency for T2 (49.11%) and T3 (44.42%) were both higher (p<0.05) than that for T1 (26.14%). A strong linear relationship existed between CPI and digestible CP (p<0.001, r2=0.988). The results from this study suggest that an adequate CP level for achieving optimal growth performance of growing Korean native goats is 15% of dietary intake. [ABSTRACT FROM AUTHOR]

Abstract: The ingredients’ particle size and dietary viscosity may alter digestion, performance and faecal waste management of fish. This study aimed to assess the effect of grinding screen sizes of feed ingredients and dietary viscosity on digestibility, faecal waste and performance of striped catfish (Pangasianodon hypophthalmus, Sauvage, 1878). The experiment had a 2 × 3 factorial‐design: two feed mesh particle sizes, by grinding ingredient mixtures at two screen sizes (0.8 versus 1.0 mm); and three dietary viscosity levels, created by exchanging carboxymethylcellulose by guar gum (GG) (0, 3 and 6 g of GG/kg of diet). Six diets were assigned to 18 tanks, each connected to three faecal settling tanks. All aquaria were stocked with 20 fish (82 g per fish). After 52 experimental days, dietary viscosity negatively affected both feed digestibility and performance of striped catfish; as a result, the amount of organic matter in the culture system through faeces had increased significantly. The coarse diets significantly increased the digestibility of dry matter and carbohydrate but worsened feed conversion ratio. Increasing dietary viscosity tended to increase the viscosity and moisture content of the faeces, but significantly accelerated the faecal disintegration through the reduction of both faecal recovery and the amount of recovered faeces. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the accuracy of fecal output measurements using polyethylene glycol (PEG) as an external marker determined by near-infrared reflectance spectroscopy. In addition, the accuracy of dry matter intake predictions based on fecal output and digestibility estimated using an internal marker [indigestible neutral detergent fiber (iNDF)] was assessed. The experiment was conducted using 6 lactating dairy cows fed 2 different diets. Polyethylene glycol was administered twice daily into the rumen and the diurnal pattern of fecal concentrations and recovery in feces were determined. To evaluate the effects of alternative marker administration and sampling schemes on fecal output estimates, the passage kinetics of PEG in the digestive tract of dairy cows was determined and used for simulation models. The results indicate that PEG was completely recovered in feces and, thus, fecal output was accurately estimated using PEG. Good agreement between measured and predicted dry matter intake (standard error of prediction = 0.86 kg/d, R2 = 0.81) indicates good potential to determine feed intake using PEG in combination with iNDF. The precision of cow-specific digestibility estimates based on iNDF was unsatisfactory, but for a group of cows iNDF provided an accurate estimate of dry matter digestibility. The current study indicated that, to overcome inherent day-to-day variation in feed intake and fecal output, the minimum of 4 fecal spot samples should be collected over 4 d. Preferably, these samples should be distributed evenly over the 12-h marker administration interval to compensate for the circadian variation in fecal PEG concentrations. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of the present study was to determine some prediction equations of gross energy content (GE), organic matter digestibility (OMd), gross energy digestibility (GEd) and the content of digestible (DE) and metabolizable energy (ME) of agro-industrial by-products for pigs, using the chemical composition and an in vitro digestibility method. Mean values of chemical composition (dry matter, DM; organic matter, OM; gross energy, GE; crude protein, CP; ether extract, EE; crude fiber, CF; neutral detergent fiber, NDF, and acid detergent fiber, ADF) were available from previous work and an in vitro OM digestibility method (IN VITRO) was performed. A total of eight by-products (liquid bakery by-product, brewer’s by-product, hominy feed, high-moisture corn, mayonnaise, almond meal, cocoa meal and kiwi fruit) were used in this study, and their in vivo OMd and GEd were known from previous experiments. The best equation for GE prediction was: GE = 9.58 EE + 6.50 CP + 4.28 carbohydrates (OM-CP-EE) (R 2 = 1.00; CV = 5.52). When only the chemical composition was used as independent variables, NDF and ADF were the best predictors (R 2 = 0.65–0.78; CV = 12.30–10.85) for OMd and GEd, and EE plus ADF for DE and ME (R 2 = 0.94–0.88; CV = 13.10–16.64). However, the best-fitted equations were: OMd = 30.90–0.302 ADF + 0.639 IN VITRO (R 2 = 0.95; CV = 4.99); GEd = 34.81–0.493 ADF + 0.589 IN VITRO (R 2 = 0.96; CV = 4.93); DE = 846.34 + 5.081 EE + 3.045 IN VITRO (R 2 = 0.97; CV = 8.57), and ME = 687.45 + 5.057 EE + 3.150 IN VITRO (R 2 = 0.97; CV = 9.78). Additionally, when the two high EE by-products (mayonnaise and almond meal; EE >50%) were excluded, the most accurate equations for DE and ME were: DE = 1415.96 + 2.764 IN VITRO (R 2 = 0.97; CV = 3.10), and ME = 1262.92 + 2.868 IN VITRO (R 2 = 0.97; CV = 2.68). These results indicated that GE, OMd, GEd, DE and ME may be accurately predicted from chemical composition, and especially from the in vitro OM digestibility. [ABSTRACT FROM AUTHOR]

Effects of dietary concentrate level and grass hay source were determined to evaluate a method (www2.luresext.edu/goats/research/suppconc.html) of predicting negative associative effects between feedstuffs in Boer goat wethers. Forage DM intake (g/kg BW0.75) was similar (P = .157) between growing and yearling wethers (34.9 and 30.8) and ranked 0 and 15 > 30 > 45 g/kg BW0.75of concentrate dry matter (48.5, 41.8, 25.9, and 15.2, respectively). Age and concentrate level interacted in neutral detergent fibre digestibility (57.3%, 60.6%, 61.4%, and 58.4% for growing and 56.6, 62.9, 56.8, and 30.0% for yearling wethers with 0, 15, 30, and 45 g/kg BW0.75, respectively). There was a tendency (P = .074) for an interaction in metabolizable energy (ME) intake between age and concentrate level (361, 530, 634, and 709 for growing and 363, 547, 541, and 555 kJ/kg BW0.75for yearling wethers with 0, 15, 30, and 45 g/kg BW0.75); values predicted for treatments with concentrate were 563, 631, and 619 for growing and 575, 684, and 697 kJ/kg BW0.75for yearling wethers with 15, 30, and 45 g/kg BW0.75, respectively. In conclusion, ME intake was accurately predicted for the low level of concentrate with both animal types and the moderate level with growing wethers. [ABSTRACT FROM PUBLISHER]

Objective: This study was determined the influence of virginiamycin supplementation on growth-performance and characteristics of digestion of cattle with decreasing dietary net energy value of the diet for maintenance (NEm) from 2.22 to 2.10 Mcal/kg. Methods: Eighty crossbred beef steers (298.2±6.3 kg) were used in a 152-d performance evaluation consisting of a 28-d adaptation period followed by a 124-d growing-finishing period. During the 124-d period steers were fed either a lesser energy dense (LED, 2.10 Mcal/kg (NEm) or higher energy dense (HED, 2.22 Mcal/kg (NEm) diet. Diets were fed with or without 28 mg/kg (dry matter [DM] basis) virginiamycin in a 2×2 factorial arrangement. Four Holstein steers (170.4±5.6 kg) with cannulas in the rumen (3.8 cm internal diameter) and proximal duodenum were used in 4×4 Latin square experiment to study treatment effects on characteristics of digestion. Results: Neither diet energy density nor virginiamycin affected average daily gain (p>0.10). As expected, dry matter intake and gain efficiency were greater (p<0.01) for LED- than for HED-fed steers. Virginiamycin did not affect estimated net energy value of the LED diet. Virginiamycin increased estimated NE of the HED diet. During daylight hours when the temperature humidity index averaged 81.3±2.7, virginiamycin decreased (p<0.05) ruminal temperature. Virginiamycin did not influence (p>0.10) ruminal or total tract digestion. Ruminal (p = 0.02) and total tract digestion (p<0.01) of organic matter, and digestible energy (p<0.01) were greater for HED vs LED. Ruminal microbial efficiency was lower (p<0.01) for HED vs LED diets. Conclusion: The positive effect of virginiamycin on growth performance of cattle is due to increased efficiency of energy utilization, as effects of virginiamycin on characteristics of digestion were not appreciable. Under conditions of high ambient temperature virginiamycin may reduce body temperature. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the digestion of dry matter (MS), crude protein (PC) and amino acids (AA) in dairy cows. Two cannulated cows were used for the determination of passage rate (Kp), in situ ruminal degradability (DR) and intestinal digestibility (DI) by abomasal catheter. The data to calculate Kp was analyzed with NLIN procedure by SAS, and descriptive statistics for DR and DI of MS, PC and AA from Kikuyu grass (Pennisetum clandestinum), a commercial supplement and two sources of rumen-protected AA. The study showed a Kp and a ruminal retention time of 0.036 h-1 and 27.4 h. The highest values from DR of MS and CP were from Kikuyu grass (69.0 and 61.8%) and concentrate (84.7 and 77.2%), followed by MetP (60.2 and 66.7%) and LysP (6.72 and 11.4%). The highest percentages of rumen indegradable amino acids (AADR) were from Kikuyu and concentrate, varying between 58.7 and 68% in forage, and 76.1 and 82.9% in the concentrate. The DR was 11.5 and 65.8% in LysP and MetP, respectively. The DI of AA (%AADR) varied between 42.3 and 77.4% for Kikuyu and 42.2 and 59.3% for concentrate. The values for the protected amino acids were 42.1 for LysP and 58.6 for MetP. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of dietary fat supplementation on dry dairy cows feed intake, digestion, ruminal kinetics, biohydrogenation, and abomasal flow of fatty acids (FAs). Eight Holstein rumen and abomasum fistulated dry cows (average body weight of 614 ± 59 kg), were assigned to a replicated 4 × 4 Latin square design experiment, with 21-d periods. The experimental diets were: 1) control (CON): corn- and soybean meal-based diet, with no fat source; 2) soybean oil (SO) diet with 30 g/kg dry matter (DM) of soybean oil; 3) whole raw soybean (WS) diet with 160 g/kg DM of whole raw soybean grain; 4) calcium salts of fatty acids (CS) diet with 32 g/kg DM of calcium salts of unsaturated FA. Fat-supplemented diets increased ether extract intake and digestibility without affecting DM intake. However, these diets promoted a decrease in DM and neutral-detergent fiber (NDF) total tract apparent digestibility. Fat sources decreased ruminal acetate to propionate ratio (C2:C3). In addition, SO diet increased ruminal propionate concentration and decreased C2:C3 in relation to protected sources of FA (CS and WS). Furthermore, cows fed CS diet exhibited higher ruminal pH, NH 3 -N and acetate concentration compared to those fed WS diet. Fatty acid supplementation did not alter serum glucose and urea concentration, but increased the serum cholesterol concentration. Although FA supplementation increased net energy intake of cows, energy and nitrogen balances, and microbial protein synthesis were not affected by the experimental diets. Fat supplementation had no effect on ruminal digestion neither on DM and NDF passage rates. Cows fed CS and WS diets presented higher DM and NDF ruminal digestion rates whether compared to SO one. Consequently, cows fed CS and WS had higher truly digestible NDF ruminal removal rate than those fed SO. Calcium salts of unsaturated FA increased DM and NDF rumen passage rate and decreased NDF digestibility in relation to WS diet. Fat-supplemented diets increased the abomasal flows of C18:2, trans C18:1, C18:0, C16:0 and total FA. The CS supplementation resulted in a higher abomasal flow of DM, total FA, trans C18:1, C16:0 and C18:3 when compared to WS one. On the one hand, FA supplementation increased C18:2 and C18:1 biohydrogenation rates; on the other hand, it protected FA sources decreased C18:2 and C18:1 biohydrogenation rates. In conclusion, fat-protected sources were effective to prevent FA from ruminal biohydrogenation. [ABSTRACT FROM AUTHOR]

The chinchilla ( Chinchilla laniger) is a herbivorous hystricomorph South American rodent for which no mean digesta retention times have been reported so far. Six animals (mean body mass ± standard deviation: 513 ± 99 g) on a diet of grass hay and lucerne-based pellets were given a pulse dose of a solute (cobalt- EDTA) and a particle (chromium-mordanted fibre, <2 mm) marker with subsequent frequent faecal collection. Dry matter intake was 45.2 ± 8.0 g/kg0.75/day. Mean retention times were 22.2 ± 5.3 h for solutes and 25.4 ± 5.2 h for particles, with the difference being not significant within individuals. This indicates the presence of a 'mucus-trap' colonic separation mechanism, which is in accord with morphological descriptions of the typical colonic furrow in chinchillas. Corresponding to a strategy of colonic digesta separation and caecotroph formation, secondary marker excretion peaks indicated coprophagic events that were spaced approximately 12 h apart. Given that these retention times appear longer than measures reported for rabbits ( Oryctolagus cuniculus) or guinea pigs ( Cavia procellus), it would be interesting to compare the digestive efficiency of chinchillas on high levels of dietary fibre to other species. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to evaluate the inclusion of detoxified castor meal in the diet of growing goats by the nutritional and productive performance. The study included 36 crossbred Boer goats kids (Boer × Anglo Nubian), with average initial weight of 20 kg ± 3.2 kg, in a completely randomized design with four treatments (diets with inclusion levels of detoxified castor meal of 0, 100, 200 and 300 g per kg dry matter) and nine repetitions. The castor meal was detoxified using calcium oxide in the proportion of 40 g of CaO for each kg of castor meal. Intake, digestibility, performance and metabolic characteristics were evaluated. At the end of the experiment, the animals were slaughtered and eviscerated, and after removal of the head, leather and feet, the carcass weights were measured to obtain the hot carcass weight. From the left half of the carcass, five anatomical regions and sections were individually weighed. The inclusion of detoxified castor meal linearly decreased ( P < 0.05) the intakes and digestibility of dry matter, crude protein, and metabolizable energy. There was also a linear reduction ( P < 0.05) of ingested and retained nitrogen, however, the excretion of nitrogen was not affected ( P > 0.05) by the inclusion of detoxified castor meal. The serum urea levels decreased linearly, and the microbial efficiency increased ( P < 0.05). The inclusion of detoxified castor meal reduced the performance of the goats, the cold carcass weight and the yields of commercial cuts ( P < 0.05). Thus, the inclusion of detoxified castor meal in the diets of growing beef goats causes a reduction in digestibility, intake and in the production performance of the animals. [ABSTRACT FROM AUTHOR]

Rate of barley starch digestion in the rumen is critical issue in high-grain fed beef cattle because it is associated with growth performance and health. The digestion rate of starch varies with variety, grain processing or starch content. The objectives of this study were to evaluate the effect of starch content and processing method of barley grain on in situ ruminal dry matter (DM) and starch digestion kinetics, and to develop a model to predict the rate of DM digestion of barley grain. The study was a 2 × 2 factorial arrangement of treatments: starch content (low vs. high) and processing method (PM; grinding vs. dry rolling). Ten barley samples with 5 low (571 ± 17 g/kg) and 5 high (660 ± 7 g/kg DM) starch were either ground 2 mm or dry-rolled with processing index (PI) of 0.75 (PI = bulk density processed/bulk density whole). Three beef heifers (650 kg body weight) fitted with rumen cannulas and fed diet consisting (g/kg DM) of 700 barley silage and 300 barley grain were used for in situ incubation. In situ degradation kinetics of DM, starch, neutral detergent fibre (NDF) and crude protein (CP) were estimated after 0, 2, 4, 8, 12, 24, and 48 h of ruminal incubation. Data from DM, starch, NDF and CP degradation at different times of incubation were fitted to a model y = a + b(1 − e −c(t−L) ). In vitro intestinal disappearances of DM, starch, NDF and CP of ruminal residue after 12 h of incubation were determined using a modified three-step procedure. Interactions between starch content and PM on the degradation kinetic parameters of DM, starch, NDF and CP were seldom observed. High starch barley had greater (P < 0.01) a and effective degradability (ED) of DM and starch, but it had less (P = 0.03) b of starch versus low starch barley. Ground barley had greater (P < 0.01) a, c and ED of DM and starch, and lower (P < 0.01) b compared with dry-rolled barley. Intestinal disappearance DM and starch of rumen residues were affected by both starch content and PM. Starch content of barley grain and manipulating processing method could effectively alter rumen digestion of barley grain. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ruminant gastrointestinal tract (GIT) adapts to changes in diet quality or feed intake level, but studies that investigate changes in organ fill, tissue mass, and function simultaneously are rare. We used 3 groups of 7 mature sheep each, fed at different DM intake levels (range 25–64 g kg −0.85 d −1 ) for 3 weeks preceding slaughter. We determined the mean retention times (MRT) of a solute and two different-sized particle markers (and their ratios indicating particle sorting and digesta washing) in the reticulorumen (RR) and the GIT, total tract digestibility, as well as digesta wet mass, wet organ tissue mass, and the dry matter (DM) concentration of digesta in the indvidual GIT sections. As DM intake increased, digesta wet mass in the RR and spiral colon increased by organ distension. Simultaneous increases in digesta wet mass in the omasum and small intestine were parallel to increases in organ tissue mass. DM digestiblity, MRT in the RR, measures of the RR sorting mechanism (MRT largeparticle RR/MRT smallparticle RR) and RR digesta washing (MRT particle RR/MRT solute RR) all remained constant across intake levels. Whereas the DM concentration increased in the rumen with intake, it remained significantly lower in the reticulum than in rumen. DM concentration in the omasum and abomasum remained constant, but both MRT in the distal GIT and DM concentration in the spiral and distal colon digesta decreased with increasing intake, translating into higher fecal water losses. These results indicate that the flexibility of the mature sheep's GIT ensures constant digestive functions (such as digestibility, particle sorting, digesta washing) at different intake levels but does not compensate for greater fecal water losses at increasing intakes. [ABSTRACT FROM AUTHOR]

Calves fed large amounts of milk replacer (MR) gain more body weight preweaning than calves fed less-aggressive programs; however, postweaning growth may be reduced. Limited research suggests that less than optimal digestion of the postweaned diet due to large amounts of MR with reduced dry feed intake preweaning may contribute to growth impairment postweaning. Current research was conducted to compare growth and postweaning digestion in 3-d-old male Holstein calves fed various MR programs. The MR programs were a conventional [CON; 0.44 kg of dry matter (DM) 21% crude protein (CP), 21% fat powder fed for 42 d], moderate (MOD; 0.66 kg of DM 27% CP, 17% fat powder fed for 42 d), and aggressive program (AGG; up to 0.87 kg of DM 27% CP, 17% fat powder fed for 49 d). All calves were fed a 20% CP textured starter and water ad libitum for 56 d. The trial used 96 calves (initially 41 ± 1.9 kg of body weight) received 5 wk apart in 2 groups of 48 calves. During d 51 to 56, fecal samples were collected from 5 calves per treatment randomly selected from calves in the first group. Selected nutrients and acid-insoluble ash (used as an internal flow marker) were analyzed in the starter and feces to estimate digestibility. Data were analyzed as a randomized complete block design with starting time of each group of calves as a block. Repeated measure analysis was performed on overall (0 to 56 d) data. Means were separated with a protected least significant difference test. Pen was the experimental unit. Calves fed CON had the least average daily gain [CON = 0.35, MOD = 0.51, and AGG = 0.55 kg/d; standard error of the mean (SEM) = 0.018], feed efficiency (CON = 0.35, MOD = 0.49, and AGG = 0.48 gain/feed, SEM = 0.016), and change in hip width (CON = 3.3, MOD = 4.1, and AGG = 4.1 cm, SEM = 0.20) compared with calves fed other programs. Calves fed AGG had the greatest change in BCS and least starter intake compared with calves fed the other programs. Digestibility of organic matter was 79, 78, and 68% and neutral detergent fiber was 54, 51, and 26% for calves fed programs CON, MOD, and AGG, respectively, and were least for calves fed AGG. These results indicate that postweaning digestion is lower than optimal and contributes to lower postweaning growth in calves fed aggressive compared with conventional or moderate MR programs. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess whether changing gas production (GP) recording method (GPR), substrate delivery method (MD), and fineness of substrate grinding (FG) alter in vitro GP from feed digestion with and without exogenous feed enzymes (EFE) treatment. The experiment was a 2 GPR × 2 MD × 2 FG × 2 EFE factorial arrangement using barley straw, alfalfa hay or wheat dried distillers grain with solubles (DDGS) as substrates. There was no interaction of EFE with GPR, MD or FG on GP and dry matter digestibility (DMD). Compared to automated methods, manual recording increased ( P < 0.01) GP, but enclosing substrate in bags vs. dispersing it in media reduced ( P < 0.04) GP from both alfalfa hay and DDGS. Gas production was greater ( P < 0.05) with 2 mm vs. 1 mm ground barley straw. The manual vs. automated GP recording resulted in reduced ( P < 0.01) DMD of alfalfa hay and wheat DDGS. For all three substrates, DMD was consistently higher ( P < 0.01) when enclosed in bags vs. dispersed in bottles. The DMD of alfalfa hay was improved ( P < 0.04) with reducing FG (1 vs. 2 mm). Moreover, EFE improved ( P < 0.01) the DMD of DDGS without affecting that of barley straw or alfalfa hay. These results showed that the GPR, MD and FG were little interacted with EFE effect on in vitro GP and DMD of feeds, suggesting that the impact of these factors on in vitro EFE effect is minimal. Hence, enclosing feed substrate in filter bags can be recommended to screen EFE products for feed digestion because of practical convenience. Moreover, the impacts of GPR, MD and FG on in vitro GP and DMD of feeds suggested that these factors should be carefully considered when comparing the nutritive values of various feeds using in vitro techniques. [ABSTRACT FROM AUTHOR]

The objectives were to evaluate the effect of harvest maturity of whole-crop oat (Study 1) and whole-crop barley (Study 2) on forage intake and sorting, ruminal fermentation, ruminal digestibility, and total tract digestibility when fed to beef heifers. In Study 1, 3 ruminally cannulated heifers (417 ± 5 kg) were used in a 3 × 3 Latin square design with 24-d periods. Whole-crop oat forage harvested at the late milk (LMILK), hard dough (HD), or ripe (RP) stages was fed for ad libitum intake and heifers were supplemented (1% of BW) with alfalfa pellets, barley grain, canola meal, and a mineral and vitamin pellet. Maturity at harvest for whole-crop oat did not affect (P ≥ 0.058) forage intake, DE intake, amount of forage refused, ruminal short-chain fatty acid concentration, or digestibility of DM, OM, NDF, and ADF. Ruminal starch digestibility decreased (P < 0.001) from 92.6% at the LMILK stage to 90.0% at the RP stage, with total tract starch digestibility decreasing (P = 0.043) from 95.8% at the LMILK stage to 94.8% at the RP stage. Ruminal CP digestibility was reduced at the HD stage compared with the LMILK and RP stages (P < 0.001). Mean ruminal pH was greatest for the LMILK stage (6.36; P = 0.003) compared with the HD and RP stages (6.30 and 6.28, respectively). In Study 2, 6 ruminally cannulated heifers (273 ± 16 kg) were used in a replicated 3 × 3 Latin square design with 24-d periods. Dietary treatments included ad libitum access to whole-crop barley harvested at the LMILK, HD, or RP stage and a constant rate (0.8% BW) of supplement containing alfalfa pellets, barley grain, canola meal, and a mineral and vitamin pellet. Dry matter intake, ruminal content mass, and feeding behavior were not affected by harvest maturity (P ≥ 0.16). There was a decrease in total tract digestibility of DM, OM, and NDF observed at the HD stage compared with the LMILK and RP stages (P ≤ 0.004). Ruminal NDF digestibility decreased from 69.7% at the LMILK stage to 54.4% at the HD stage and 54.9% at the RP stage (P = 0.001), whereas ruminal ADF digestibility decreased from 70.0% at the LMILK stage to 44.4% at the HD stage and 42.5% at the RP stage (P = 0.002). Minimum and mean ruminal pH were least for the LMILK stage, intermediate at the RP stage, and greatest at the HD stage (P = 0.016 and P = 0.031, respectively). These data suggest that despite reductions in ruminal digestibility of NDF and ADF with advancing maturity, harvesting whole-crop oat and barley forage at the HD and RP stages of maturity did not negatively affect DMI, fermentation characteristics, or DE relative to whole-crop cereal forage harvested at the LMILK stage. [ABSTRACT FROM AUTHOR]

The aim of the current study was to compare the effect of different physical processing methods including roasting at 140 °C for 15 (R15) or 30 minutes (R30), gamma ray irradiation (γ-irradiation) at doses of 15 (γ15), 30 (γ30) and 45 (γ45) kGy, and microwaving at 800 W for 2 (MW2), 4 (MW4) and 6 minutes (MW6) of whole cottonseed (WCS) on ruminal degradation. In vitro crude protein (CP) digestibility and gossypol contents were compared as well. In situ experiment was conducted on three permanent rumen-fistulated bulls. Gossypol content was decreased among treatments (p<0.05). The lowest degradation rate of protein in rumen was obtained for γ45 treatment. The rate of degradation of the potentially degradation fraction was decreased for both dry matter (DM) (p=0.002) and CP (p=0.006) with different treatments. The lowest values for effective degradation in all passage rates were obtained with γ45. Both microwaving and γ irradiation showed difference for CP effective degradability parameter. The greatest value of in vitro CP digestibility (p<0.05) was observed for a dose of 45 kGy gamma-irradiated cottonseed compared to untreated WCS. Based on the results, γ ray irradiation with 45 kGy was the most effective processing method in both reducing the gossypol content and escaping the protein through rumen for WCS in ruminant nutrition. [ABSTRACT FROM AUTHOR]

A 21-day trial was conducted to find out the digestibility and utilization of biscuit waste meal/Leucaena leucocephala leaf hay (B WM/Llh) mixture in the diet of growing sheep. The test mixture was used to formulate diets in which it replaced maize/wheat offal mixture at 0 (control), 25, 50, 75 and 100% inclusion levels and were designated as B0, B25, B50, B75 and B100 respectively. Twenty entire Yankassa rams with average initial live weight of 12.16±0.34kg were used in the completely randomized design experiment with 4 animals per treatment. Statistical analysis result showed that the Dry Matter intake (g/d) values of 673.73, 664.63 and 653.17 obtained on diets B25, B50 and B75 were each higher (p<0.005) than (647.23) offered to the control. Percentage Dry Matter digestibil-ity decreased (p<0.05) from 87.54, 83.60, 77.90, 77.30 and 75.50 respectively in sheep receiving the test mixture diets. The digestibilities of crude protein, crude fibre and its fractions, nitrogen free extraction and energy which followed the same pattern as dry matter digestibility decreased (P<0.05) as the level of BWM/Llh mixture increased. However nitrogen absorbed and retained by ani-mals on the mixture based diets B25, B50 and the control (B0) were similar (P> 0.05). In conclusion, replacing maize, wheat offal mixture with biscuit waste meal, Leucaena leucocephala leaf hay mixture may be used until less than 75% in the diet of growing sheep. [ABSTRACT FROM AUTHOR]

The present study was undertaken to evaluate the potential for using oilseed by-products (soybean, copra and palm kernel meals) as partial replacements of fishmeal in feeds for Nile tilapia ( Oreochromis niloticus). Nutrient digestibility and postprandial ammonia excretion rates were examined. A fishmeal-based diet served as control against three test diets in which 30 % of each of the oilseed by-products was included. Diets were randomly assigned to triplicate groups of fish (~1 kg bulk weight) for the digestibility trials which spanned a total of 9 days. The partial inclusion of oilseed meals did not significantly affect apparent protein digestibility, although lipid, ash and dry matter digestibilities were significantly affected ( p < 0.05). Fish fed the soybean meal diets significantly reduced their feed intake and showed lower growth and feed utilization efficiencies over the trial period. The inclusions of the plant proteins caused a reduction in ammonia excretion rates with the palm kernel meal diet recording the lowest mean excretion rates of 117 mg kgday which was twofold lower than the highest mean daily ammonia excretion rate of the fish group fed the fishmeal-based control diets. Overall, the study confirmed the potential of using copra and palm kernel meals to partially replace fishmeal in Nile tilapia diets based on their effects on short-term growth and feed utilization, nutrient digestibilities and lower ammonia excretion rates, while soybean meal in an unrefined form is not a promising replacement for fishmeal in tilapia diets. [ABSTRACT FROM AUTHOR]

The objective of the current work was to parameterize the digestive elements of the model of Hill et al. (2008) using data collected from animals that were ruminally, duodenally, and ileally cannulated, thereby providing a better understanding of the digestion and metabolism of P fractions in growing and lactating cattle. The model of Hill et al. (2008) was fitted and evaluated for adequacy using the data from 6 animal studies. We hypothesized that sufficient data would be available to estimate P digestion and metabolism parameters and that these parameters would be sufficient to derive P bioavailabilities of a range of feed ingredients. Inputs to the model were dry matter intake; total feed P concentration (fPtFd); phytate (Pp), organic (Po), and inorganic (Pi) P as fractions of total P (fPpPt, fPoPt, fPiPt); microbial growth; amount of Pi and Pp infused into the omasum or ileum; milk yield; and BW. The available data were sufficient to derive all model parameters of interest. The final model predicted that given 75 g/d of total P input, the total-tract digestibility of P was 40.8%, Pp digestibility in the rumen was 92.4%, and in the total-tract was 94.7%. Blood P recycling to the rumen was a major source of Pi flow into the small intestine, and the primary route of excretion. A large proportion of Pi flowing to the small intestine was absorbed; however, additional Pi was absorbed from the large intestine (3.15%). Absorption of Pi from the small intestine was regulated, and given the large flux of salivary P recycling, the effective fractional small intestine absorption of available P derived from the diet was 41.6% at requirements. Milk synthesis used 16% of total absorbed P, and less than 1% was excreted in urine. The resulting model could be used to derive P bioavailabilities of commonly used feedstuffs in cattle production. [ABSTRACT FROM AUTHOR]

The objective of the present experiment was to determine the true ileal calcium (Ca) digestibility in three samples of meat and bone meal (coded as MBM-1, MBM-2 and MBM-3) for broiler chickens. Four experimental diets, containing graded concentrations of Ca, were formulated from each MBM sample with inclusion levels of 20, 40, 60 and 80 g/kg diet. Each experimental diet was randomly allotted to four replicate cages (six birds per cage) and fed for three days from day 28 post-hatch. Apparent ileal digestibility coefficient of Ca was measured by the indicator method and linear regression analysis was used to determine the true Ca digestibility coefficient. Apparent Ca digestibility was unaffected ( P > 0.05) by increasing Ca concentrations. The apparent digestibility coefficients in MBM-1, MBM-2 and MBM-3 were 0.50, 0.44 and 0.45, respectively. Significant linear ( P < 0.001) relationship was observed between dietary Ca intake and digesta Ca output for MBM-1, MBM-2 and MBM-3 with R 2 values of 0.82, 0.93 and 0.95, respectively. The true ileal digestibility coefficients of Ca in MBM-1, MBM-2 and MBM-3 were determined to be 0.60, 0.46 and 0.50, respectively. The corresponding ileal endogenous Ca losses were 292, 123 and 174 mg/kg dry matter intake, respectively. [ABSTRACT FROM AUTHOR]

Three multiparous lactating Holstein cows averaging 699 kg of body weight (SE = 76.2) were allotted in a 3 × 3 Latin square design to determine the nutrient profile of flaxseed recovered from the faeces of dairy cows fed different amounts of whole flaxseed and to compare the chemical composition of dietary flaxseed to that of flaxseed recovered from faeces. The three dietary treatments consisted of three total mixed diets containing 50, 75 or 100 g/kg dry matter (DM) whole flaxseed. Milk production, milk composition and total tract apparent digestibility (TTAD) were also determined. Intake of DM, milk yield and composition, production of milk components and TTAD of acid detergent fibre (ADF) and ether extract (EE) were similar among treatments. Total tract apparent digestibility of DM and crude protein (CP) decreased linearly with higher concentration of whole flaxseed in the diet and TTAD of neutral detergent fibre (aNDF) was quadratically affected. Composition of flaxseed recovered from the faeces of cows fed the three diets was generally similar. Concentrations of CP and EE in flaxseed recovered from the faeces were lower and higher, respectively, compared to those of flaxseed consumed by cows and there was no difference in aNDF and ADF concentrations. Proportions of 14:0, 15:0, 16:0, 17:0, trans 11-18:1, cis 9, trans 11-18:2, and 20:0 in flaxseed recovered from the faeces decreased linearly with greater proportions of dietary flaxseed and that of cis 9,12,15-18:3 increased. Proportions of 16:0 and cis 9-16:1 decreased linearly and those of trans9-18:1, trans 13+14-18:1+ cis 6+8-18:1, 19:0, cis 9, cis 12, cis 15-18:3 increased linearly in milk fat with higher amounts of whole flaxseed in the diet. The amount of flaxseed recovered in faeces increased in parallel with the amount consumed. However, the linear decrease in TTAD of DM and CP with increasing proportion of whole flaxseed in the diet and the trend for better TTAD of aNDF for cows fed 50 g/kg DM than for those fed greater amounts of whole flaxseed suggest that productivity of dairy cows could be negatively affected when feeding more than 50 g/kg DM whole flaxseed. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of the forage shrub tedera (Bituminaria bituminosa) on nutrient digestibility, rumen microbial fermentation and furanocoumarins degradation in the rusitec. The variables were measured in fermentation liquid on Days 13 and 17 and were compared with a control (lucerne hay). Overall, tedera had greater (P < 0.05) neutral detergent fibre and acid detergent fibre digestibility than lucerne hay on both days of the experiment, but on Day 17 it had lower (P < 0.01) dry matter and crude protein digestibility than lucerne hay. There were no significant differences in concentration of NH3-N and pH between treatments, but NH3-N concentrations in both treatments were lower (P < 0.05) on Day 17 than on Day 13. The concentration of total volatile fatty acids in vessels were not affected by treatments, but the concentration of acetate was lower and acetate-to-propionate ratio higher (P < 0.05) in tedera than lucerne hay on Day 13 of the experiment. Furanocoumarins were detected in the tedera treatment only. Their concentration in the fermentation liquid increased immediately after the addition of the plant material to the fermenter, reaching highest concentrations after 2 h. These concentrations gradually declined over the next two sampling times, but 6 h after the 'feeding', they were still detectable in the fermentation liquid. It was concluded that (i) tedera had in vitro digestibility and fermentability variables comparable to lucerne; (ii) furanocoumarins were degraded in the fermentation fluid, and (iii) furanocoumarins from tedera did not seem to impede microbial fermentation. Tedera may provide an alternative feed source to hay and grain for filling the summer-autumn feed gap without negatively affecting nutrient digestibility and rumen microbial fermentation. Tedera is a perennial pasture containing secondary compounds that has the potential to be utilised in the farm systems during the summer-autumn feed gap and reducing supplementary feeding. In our study, we showed that tedera was fermented without any adverse effects on digestibility or fermentability. These findings give further support for pursuing tedera as a fodder for growing regions of Australia. [ABSTRACT FROM AUTHOR]

The objectives of this study were to measure voluntary herbage intake in kg of dry matter (DM) per day and in proportions of plant species and components (leaf, stem, dead material) of nonlactating Angus cows under grazing conditions and compare DM herbage intakes to intakes of the same cows when they were nursing their calves. Twenty nonlactating Angus cows (50±12 mo of age, 525±55 kg weight) were selected from a larger herd to create 4 groups of 5 cows with average DM intakes that ranged from 11 to 15 kg/d during lactation. The cows were allocated for 28 d as a group on the pasture that contained 5540 kg DM/ha as tall fescue ( Festuca arundinacea ), bermudagrass ( Cynodon dactylon var. Tifton-85), red clover ( Trifolium pratense ) and other plants. Pasture composition was measured by visual appraisal and manual separation of pasture clippings. Daily allocations provided approximately 2.5 kg DM/100 kg BW. Each cow was individually fed 0.82 kg supplement DM daily that contained 498 mg of the n -alkane dotriacontane (C32) and 448 mg hexatriacontane (C36) during the last 14 d. Fecal grab samples were collected from each cow during the last 5 d. Grazing intake (8.92±1.5 kg DM/d) was calculated for each cow from C32 intake and ratios of tritriacontane (C33):C32 in feces and did not differ ( P =0.97) among cow groups. Individual cow intakes during lactation and after weaning, during grazing, were not correlated. Measured sward and calculated intake proportions of tall fescue (0.58 and 0.65), bermudagrass (0.38 and 0.33), and red clover (0.02 and 0.01) indicated cows selected slightly more tall fescue and less bermudagrass and red clover than was on offer. Manual separations of sward and calculated intake proportions of dead material and stem (0.89 and 0.95), green leaf (0.10 and 0.02) and other material (0.01 and 0.04) were similar. N -alkanes provided credible calculations of intake by grazing cows. Intakes of lactating cows did not predict their intake after weaning. [ABSTRACT FROM AUTHOR]

Copyright of Ciência Animal Brasileira is the property of Universidade Federal de Goias, Escola de Veterinaria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study appraised the effects of Carotino oil on in vitro rumen fermentation, gas production, metabolism and apparent biohydrogenation of oleic, linoleic and linolenic acids. Carotino oil was added to a basal diet (50% concentrate and 50% oil palm frond) at the rate of 0, 2, 4, 6 and 8% dry matter of the diet. Rumen inoculum was obtained from three fistulated Boer bucks and incubated with 200 mg of each treatment for 24 h at 39°C. Gas production, fermentation kinetics, in vitro organic matter digestibility ( IVOMD), volatile fatty acids ( VFA), in vitro dry matter digestibility ( IVDMD), metabolizable energy and free fatty acids were determined. Carotino oil did not affect ( P > 0.05) gas production, metabolizable energy, pH, IVOMD, IVDMD, methane, total and individual VFAs. However, Carotino oil decreased ( P < 0.05) the biohydrogenation of linoleic and linolenic acids but enhanced ( P < 0.05) the biohydrogenation of oleic acid. After 24 h incubation, the concentrations of stearic, palmitic, pentadecanoic, myristic, myristoleic and lauric acids decreased ( P < 0.05) while the concentration of linolenic, linoleic, oleic and transvaccenic acids and conjugated linoleic acid ( CLAc9t11) increased ( P < 0.05) with increasing levels of Carotino oil. Carotino oil seems to enhance the accumulation of beneficial unsaturated fatty acids without disrupting rumen fermentation. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the coefficient of total tract apparent digestibility (CTTAD) and coefficient of total tract standardized digestibility (CTTSD) of phosphorus (P) in nine corn sources fed to growing-finishing pigs. Ten barrows (initial of BW, 55.8 ± 3.0 kg) were individually housed in metabolism cages. Experimental diets consisted of nine different corns and one P-free diet for measurement of basal endogenous loss of P. Corn sources included 5 yellow-corns from the United States (USY-1 to 5), 2 yellow-corns from South Africa (SAY-1 and 2), and 2 white-corns from South Africa (SAW-1 and 2). Pigs were arranged in a 10 × 8 incomplete Latin square design with 10 diets and 8 periods. The CTTAD of dry matter (DM) in SAW-1 was greater ( P < 0.01) than that of USY-3, USY-5 or SAY-2. Pigs fed SAW-1 showed greater ( P < 0.01) CTTAD of nitrogen (N) than those fed USY-3, USY5 or SAY-2. The CTTAD and CTTSD of P across the nine corns averaged 0.43 and 0.49, respectively, but the values were not significantly different among the corn grains. In conclusion, the digestibility of DM and N varies in corn and needs to be determined to improve the efficiency with which the grain and corn based diets are utilized by growing pigs. [ABSTRACT FROM AUTHOR]

Two malting barley varieties, AC Metcalfe and CDC Copeland, were grown at seven sites in Canada with varying seeding rates (SR; 200 and 400 seeds/m 2 ) and nitrogen fertilization rates (NR; 0, 30, 60, 90, and 120 kg/ha) and were assessed for variation in chemical composition, gas production (GP), and dry matter digestibility (DMD) after 24 h of batch culture. The variety affected (P<0.01) the crude protein (CP) content of malting barley grain and interacted with SR or NR on DMD. The increase in NR quadratically increased (P<0.01) CP and fiber content but linearly (P<0.01) decreased starch content of malting barley grain. Variety, SR, and NR had limited impact on in vitro GP and DMD. This study showed substantial variation in CP content and DMD among samples and that the chemical composition of malting barley grain and its potential feed value could be altered by NR. [ABSTRACT FROM AUTHOR]

The objectives of this study were to evaluate the effects of volume weight (VW; g/L), processing method (PM; control vs. precision processing [PP]), and processing index (PI; VW after rolling/VW before rolling) of barley grain on in situ ruminal kinetics and in vitro intestinal digestion. The study was designed as a 2 × 2 × 2 factorial arrangement of treatments: VW (low vs. high), PM (control vs. PP) and PI (0.75 vs. 0.85). Ten barley samples, 5 low (580 g/L) and 5 high (680 g/L) VW, were either dry-rolled with a single roller setting (control) or screened into two fractions of small or large kernels using a 4-mm sieve, and then dry-rolled (i.e., PP). Each sample was dry-rolled moderately or coarsely with PI of 0.75 or 0.85. Three beef heifers (650 ± 25.5 kg body weight) fitted with rumen cannulas and fed a diet consisting of 700 g/kg barley silage and 300 g/kg concentrate mix (dry matter [DM] basis) were used for the in situ study. In situ degradation kinetics of DM and starch were estimated after 0, 3, 6, 12, 24 and 48 h of ruminal incubation. Data from DM and starch degradation at different times of incubation were fitted to a model y = a + b (1 − e − c ( t − L ) ). in vitro intestinal disappearances of DM and starch of ruminal residue after 12 h of incubation were determined using a modified three-step procedure. Interactions between VW and PM on effective degradability (ED; P<0.01) and between PM and PI on the degradation kinetics (P<0.05) were observed. The VW of barley grain did not affect the degradation kinetics of DM and starch whereas ED of DM was greater (P<0.01) in high versus low VW in the control samples. For in situ DM disappearance, a (P<0.01) and b (P<0.07) fractions were lower, but c and ED were higher (P<0.01) in PP versus control samples. Increased processing of barley consistently resulted in greater (P<0.01) values of degradation kinetics and ED compared with less processed barley. Intestinal DM disappearance of rumen residues was affected by all three factors (VW, PM and PI). Regression results showed that the rate of DM disappearance was correlated to the particle size distribution and the fine particles were the primary predictor. The results demonstrated that the PP approach and manipulating PI are effective ways to optimize rumen digestion of barley grain. This suggests that a concise and reliable method to predict rumen digestion of barley may be developed based on measuring the fines content of processed barley. [ABSTRACT FROM AUTHOR]

An in vivo study was performed to validate an in vitro procedure that predicts rate of fiber digestion and total-tract neutral detergent fiber digestibility (TTNDFD). Two corn silages that differed in fiber digestibility were used in this trial. The corn silage with lower fiber digestibility (LFDCS) had the TTNDFD prediction of 36.0% of total NDF, whereas TTNDFD for the corn silage with higher fiber digestibility (HFDCS) was 44.9% of total neutral detergent fiber (NDF). Two diets (1 with LFDCS and 1 with HFDCS) were formulated and analyzed using the in vitro assay to predict the TTNDFD and rumen potentially digestible NDF (pdNDF) digestion rate. Similar diets were fed to 8 ruminally can-nulated, multiparous, high-producing dairy cows in 2 replicated 4x4 Latin squares with 21-d periods. A 2 x 2 factorial arrangement of treatments was used with main effects of intake (restricted to approximately 90% of ad libitum intake vs. ad libitum) and corn silage of different fiber digestibility. Treatments were restricted and ad libitum LFDCS as well as restricted and ad libitum HFDCS. The input and output values predicted from the in vitro model were compared with in vivo measurements. The pdNDF intake predicted by the in vitro model was similar to pdNDF intake observed in vivo. Also, the pdNDF digestion rate predicted in vitro was similar to what was observed in vivo. The in vitro method predicted TTNDFD of 50.2% for HFDCS and 42.9% for LFDCS as a percentage of total NDF in the diets, whereas the in vivo measurements of TTNDFD averaged 50.3 and 48.6% of total NDF for the HFDCS and LFDCS diets, respectively. The in vitro TTNDFD assay predicted total-tract NDF digestibility of HFDCS diets similar to the digestibility observed in vivo, but for LFDCS diets the assay underestimated the digestibility compared with in vivo. When the in vitro and in vivo measurements were compared without intake effect (ad libitum and restricted) considering only diet effect of silage fiber digestibility (HFDCS and LFDCS), no differences were observed between methods. These values suggest that our in vitro TTNDFD model could be used to predicted rate of fiber digestion and NDF digestibility for dairy cattle. [ABSTRACT FROM AUTHOR]

Omnivorous fish utilize dietary carbohydrates better than carnivorous ones due to striking morphological and physiological differences in their digestive tracts. However, digestive tract morphology and physiology also varies among omnivorous fishes, which can lead to different dietary utilization of plant sources as well. Starch, energy, and dry matter apparent digestibility coefficient (ADC) of wheat bran, cassava residue, ground corn, and broken rice were compared between the omnivorous freshwater jundiá catfish (93.9 ± 34.0 g; mean ± standard deviation) and Nile tilapia (93.7 ± 51.6 g) by using 5 g kg − 1 chromic oxide as a diet marker. Starch ADCs were significantly higher in tilapia for all plant sources (92.02% to 99.74% versus 55.87% to 90.61%), except for wheat bran, which was similar to that found in jundiá. Starch-richer plant sources (ground corn and broken rice) showed the lowest starch digestibility for jundiá. However, ground corn provided significantly higher energy digestibility in jundiá (55.35%), as opposed to broken rice (86.59%) and ground corn (71.68%), in tilapia. Dry matter ADCs ranged from 22.89% for cassava residue in jundiá to 89.17% for broken rice in tilapia. Higher dry matter ADCs were registered in tilapia for all plant sources, except for wheat bran. Despite presenting lower starch and energy digestibilities, jundiá catfish showed an adaptive capacity to utilize starch sources by presenting significantly higher specific activity of amylase (58 U mg protein − 1 versus 29 U mg protein − 1 ) and maltase than Nile tilapia for all plant sources, except for wheat bran. Maltase activities in the gut of jundiá varied from 2.5 to 3.6 U mg protein − 1 , depending on the plant source, while in tilapia it averaged 1.7 U mg protein − 1 , regardless of the plant source. The scanning electron microscopy approach used to study the influence of fish digestion on the structure of starch granules from different plant sources revealed the presence of spherulites in the fish feces. Starch spherulite formation in jundiá intestines could be related to lower starch digestibility. Our findings demonstrate different carbohydrate digestion abilities among omnivores. [ABSTRACT FROM AUTHOR]

This study was performed to evaluate the impact of dietary protein levels on nutrient digestibility and water and nitrogen balances in conditioning eventing horses. Twenty-four Brazilian Sport Horses, male and female (8.0 to 15.0 yr; 488 ± 32 kg BW), were used in a randomized design with 4 levels of CP diets: 7.5%, 9.0%, 11.0%, and 13.0%. A digestion assay was performed with partial feces collection over 4 d, followed by 1 d of total urine collection. Data were submitted to regression analysis and adjusted to linear and quadratic models (P < 0.05). No differences were observed in the intake of DM, OM, EE, ADF, and NDF as a function of dietary protein levels. Dry matter intake average was 1.7% of BW. CP and N intake showed a linear increase as a function of increasing protein level in diets. A quadratic response (P < 0.05) was observed on the CP and NDF digestibility coefficients, with the maximum estimated level of digestibility at 11.6% and 11.4% CP in the diet, respectively. There was a linear effect on ADF digestibility coefficients, digestible DM and protein intake, and CP/DE ratio according to dietary protein levels. There was no impact of dietary protein levels on daily water intake, total water intake, or fecal water excretion. Urinary excretion values showed a linear increase in response to increased dietary protein levels, but no impact was observed on water balance, with an average of 8.4 L/d. Nitrogen intake (NI), N absorption (NA), and urinary N increased linearly as a function of increasing dietary protein levels. There was no impact of dietary protein levels on N retention (NR), with an average of 7.5 g N/d. Nitrogen retention as a percentage of NI or NA showed no significant changes in the function of dietary protein levels. There was an impact of dietary protein levels on the digestibility coefficient of CP, NDF, ADF, and digestible protein intake on conditioning eventing horses. The 11.6% CP level in the diet provided an intake of 2.25 g CP/kg BW and 0.37 g N/ kg BW, and this intake was the most appropriate for the conditioning of intensely exercised horses, considering the responses related to NI, NA, and the estimated NR to NA ratio. The NDF and ADF responses indicated that dietary fiber was more digested with an increased amount of N in the digestive tract. [ABSTRACT FROM AUTHOR]

The chemical characteristics of co-products recovered during a laboratory-scale wet milling procedure as well as that of whole corn flour were characterised and their digestibility and fermentability value determined using a 2 steps in vitro digestibility and fermentation model of the pig digestive tract. Five co-products differing in their chemical composition were collected and analysed. These co-products differed in their in vitro dry matter Digestibility and in their kinetic of fermentation. High coefficients of digestibility were observed for starchy samples, while low coefficients of digestibility were observed for samples rich in lignocellulosic components. Fermentation patterns of samples analysed were different as well as the profile of volatile fatty acids produced during the fermentation. The production of straight-chain fatty acids produced was significantly correlated with the proportion of starch in the sample, while branched-chain fatty acids were correlated to proteins concentration of samples. [ABSTRACT FROM AUTHOR]

The aim of this study was to validate an enzymatic in vitro method that estimates the apparent total tract digestibility (ATTD) of phosphorus (P) in feed ingredients from plant origin used in pig nutrition. Sixteen individually housed castrated male pigs (19.5 ± 2.9 kg) were fed a semisynthetic diet, either alone (control) or containing: wheat, barley, maize, potato protein concentrate, soybean expeller or rapeseed expeller for periods of 14 days. The ATTD of P was determined indirectly using celite as a marker. The in vitro released P was determined after three consecutive steps: preliminary soaking in acid medium, pepsin digestion in strong acid medium and pancreatin digestion in neutral medium. The in vivo ATTD of P were 0.21, 0.37, 0.48, 0.41, 0.33 and 0.39 in the respective feed ingredients as listed above. The in vivo ATTD of P and the in vitro released P were linearly correlated ( in vitro released P = −0.118 (P>0.10) + 1.171 (P<0.01) × in vivo ATTD of P, R 2 = 0.91). Thus, the in vitro method was successful in predicting in vivo ATTD of P in the plant feed ingredients tested here. The in vitro method can be proposed as an inexpensive tool to rapidly estimate ATTD of P in plant feed ingredients. [ABSTRACT FROM AUTHOR]

Fiber digestibility is an important factor regulating DMI in ruminants. Additionally, the ensiling process can also affect digestibility and chemical composition of the forage. The objective of this study was to investigate effects of sugarcane NDF digestibility (NDFD) and conservation method on intake, mmen kinetics, and the mminal ecosystem of steers. Eight ruminally cannulated Nellore steers (275 ± 22 kg BW) were used in a replicated 44 Latin square design with a 2 x 2 factorial arrangement of treatments. Two sugarcane genotypes divergent for stalk NDFD were used: IAC86-2480 with high NDFD and SP91-1049 with low NDFD. Experimental diets were formulated with 40% sugarcane, either freshly cut or as silage, and 60% concentrate on a DM basis. Each experimental period lasted for 14 d, with the last 4 d used for determination of intake, mminal evacuation, and mminal fluid collection. The effect of fiber digestibility on DM and NDF intake was dependent on the forage conservation method (P = 0.01). High NDFD increased (P <0.01) DMI only when sugarcane was offered as silage, having no effect (P = 0.41) on DMI when offered as freshly cut. Conservation method had no effect on total mminal mass, with only a tendency (P < 0.10) for greater NDF and indigestible NDF mminal mass in steers fed the low-NDFD genotype. The NDF turnover and passage rates were greater (P < 0.05) for the genotype with high NDFD but only when offered as silage. Liquid turnover rate in the mmen was greater (P = 0.02) for diets containing silage, with no effect of genotype (P = 0.87). There was no effect of NDFD genotype on mminal pH (P = 0.77); however, diets containing sugarcane as silage increased (P < 0.01) mminal pH. Total concentration of short chain fatty acids (P = 0.05) and proportions of propionate (P = 0.01) were greater for diets containing fresh sugarcane. Diets with fresh sugarcane increased the mminal population of Streptococcus bovis (P< 0.01) and Ruminococcus albus (P = 0.03). The relative population ofR. albus was also greater (P = 0.04) for diets containing the sugarcane genotype with high NDFD. Feeding diets containing the sugarcane genotype with high NDFD increased Fibrobacter succinogenes population but only when sugarcane was fed as freshly cut (P = 0.02). Using sugarcane genotypes with high NDFD can increase intake and benefit fiber-degrading bacteria in the mmen. [ABSTRACT FROM AUTHOR]

A pig digestibility trial was conducted to investigate the effects of fermentation or extrusion of wheat bran included in a basal diet on coefficients of total tract apparent digestibility (CTTAD) regarding dry matter (DM), organic matter (OM), crude protein (CP), crude fiber (CF), ether extract (EE), starch, energy (GE), phosphorus (P) and calcium (Ca). In the experiment, 9 growing pigs were allocated to a 3 × 3 Latin square design to measure the CTTAD of the basal diet containing different modified wheat bran variants, and therefore to demonstrate relative differences in the CTTAD among the diets as a result of wheat bran modification. The wheat bran was used in native form (NWB), as fermented bran ensiled with Lactobacillus paracasei and Lactobacillus plantarum (FWB) and as extruded wheat bran (EWB). Wheat bran variants were included at 200 g kg −1 in a phosphorus deficient basal diet. The obtained results show that the CTTAD of DM was increased when feeding the diet with FWB (+2%, P <0.05) instead of NWB (0.87). Likewise the CTTAD of OM was also increased with FWB (+2%, P <0.05), compared to NWB (0.88). Also the CTTAD of CF was improved with FWB and EWB (+9%, P <0.05), related to NWB (0.58). The CTTAD of ash was improved with FWB (+14%, P <0.05) compared to NWB (0.60). Correspondingly, the CTTAD values of P and Ca were also elevated when feeding the FWB diet. P-digestibility was increased in the FWB feeding group compared to those groups fed with NWB (+35%, P <0.05) and EWB (+53%, P <0.05). Regarding the Ca digestibility, similar results were obtained ( P <0.05). While the CTTAD of energy was increased in the FWB (+3%, P <0.05) and EWB (+2%, P <0.05) feeding groups compared to that of NWB (0.85), the N-balance and the CTTAD of starch were not affected by the treatments. Nevertheless, the CTTAD of EE was enhanced in the FWB treatment group (+40%, P <0.05), and was also improved by extrusion (+30%, P <0.05) compared to the NWB (0.50) treatment. In conclusion, fermented and extruded wheat bran exert some significant influence on the apparent total tact digestibility of several essential nutrients, minerals and energy when included in a basal diet, whereby fermentation seems to be the more potent strategy, as positive effects on the CTTAD of P and Ca could only be observed in the feeding group with FWB. [ABSTRACT FROM AUTHOR]

Dry matter digestibility is a critical component of herbage nutritive value, a major service delivered by grasslands. The aim of this study was to test whether the dominance hypothesis applies to assess the impacts of environmental gradients and management regimes on this component of herbage nutritive value in permanent grasslands., At the plant level, digestibility has been related to a number of functional traits, but whether this can be scaled up to the community level in species-rich grasslands and how such relationships are modulated by environmental conditions and management regimes remain unknown. Our primary objective was to test whether community-weighted means - species trait values weighted by the species abundance - of morphological, phenological and chemical traits could be used to explain variations in digestibility over a large range of climatic contexts, soil resource levels and management regimes. Our second objective was to explain variations in community digestibility within and among nine contrasting sites along large natural and man-induced environmental gradients., Over the whole data set, digestibility and most community-weighted means of traits responded to climatic factors and management regimes, but relations were not always significant when each site was considered separately. Community digestibility was significantly related to one or more plant traits within each site and to all of the measured traits when considering all the sites. Leaf dry matter content ( LDMC) had the most consistent effects on digestibility, with a strikingly similar negative effect within each site. Potential evapotranspiration was negatively related to digestibility and contributed to explain a large part of the among-site variance. In addition, a low return interval of disturbance and a high disturbance intensity (biomass removal) were both associated with a high digestibility., Synthesis and applications. Disturbance regime, plant traits and local climate impacted dry matter digestibility roughly equally in grasslands. The effects of community composition on digestibility and its response to abiotic factors could be successfully captured by community-weighted means of leaf dry matter content. This functional marker can be used to develop indicators and grassland management rules to support farmers in the refinement of their practices towards specific needs, such as target production outputs. [ABSTRACT FROM AUTHOR]