Neutral Detergent Fiber Intake Research Articles

Levels and degradability of crude protein in digestive metabolism and performance of dairy cows

Two experiments were conducted to evaluate the effect of the level and degradability of crude protein (CP) on the digestive metabolism and productive performance of dairy cows. In both experiments, 15 Holstein cows with 585 ± 40 kg of body weight were distributed in a Latin square design with five contemporary squares, three periods of 21 days and three treatments. In experiment 1, treatments consisted of three CP levels (130, 160 or 180 g CP/kg DM), while in experiment 2, the treatments consisted of three levels of rumen degradable protein (RDP; 80, 100 or 120 g RDP/kg DM) in diets with average of 163 g CP/kg DM. Variables evaluated in both experiments were dry matter intake (DMI), total apparent digestibility, milk yield (MY) and composition, ruminal fermentation and N balance. In experiment 1, the increase of CP from 130 to 180 linearly increased the organic matter, CP, neutral detergent fiber (NDF) and acid detergent fiber (ADF) intake (kg) and the apparent total digestibility coefficient of DM and CP. In addition, a linear increase of MY, fat corrected milk (FCM) and daily production of fat, protein, lactose, casein and total solids was observed. A linear increase in ruminal ammoniacal nitrogen (NH3-N) concentration and nitrogen excretion in milk, feces and urine was also observed. However, there was no observed effect on SCFA concentration. In experiment 2, the increase of the RDP from 80 to 120 increased the DMI, MY, FCM, milk protein content and digestibility coefficient of the NDF, ADF and ethereal extract. Additionally, there was an increase in NH3-N concentration and milk nitrogen excretion. The studies indicated that the increase of CP content up to 100 g RDP/kg DM increased the DMI and the productive performance of the cows, but also increased urine N. Thus, it is desirable that the increase of the CP through the increase of the RDP is carried out up to 100 g of RDP/kg DM, since there is elimination of nitrogen, decrease of milk yield and decrease of propionic acid in values above that level.

Lactation performance, nitrogen utilization, and profitability in dairy cows fed fermented total mixed ration containing wet corn gluten feed and corn stover in combination replacing a portion of alfalfa hay

To effectively use corn by-products for ruminants, lactation performance, nitrogen utilization, and profitability in lactating dairy cows fed fermented total mixed ration (FTMR) that contained wet corn gluten feed (WCGF) and corn stover in combination replacing a portion of alfalfa hay were studied. Thirty-six multiparous Holstein dairy cows (602 ± 46.8 kg of body weight; 109 ± 18.5 day in milk; 30.1 ± 1.53 kg of milk production; and 2.44 ± 0. 51 of parity; mean ± SD) were blocked into 12 groups based on DIM, milk production, and parity and were allocated randomly to 1 of 3 diets for a 14-week period, with the first 2 weeks allowed for adaptation to the diets. The TMR was prepared with same mixed ration of concentrate mixtures and corn silage but different proportions of alfalfa hay, corn stover and WCGF. The treatments were designed as (1) TMR A containing 220 g/kg DM alfalfa hay; (2) TMR B containing 118 g/kg DM alfalfa hay, 68.8 g/kg DM WCGF, and 34.4 g/kg DM corn stover; and (3) Fermented TMR (FTMR) prepared with same ingredient as TMR B. The FTMR diet had higher crude protein (CP) and lactic acid contents content, the ratio of ammonia nitrogen to total N while decreased pH value, neutral detergent fiber (NDF), acid detergent fiber (ADF) and dry matter (DM) content compared to other two diets. The milk fat concentration, milk fat yield, DM and CP degradation, estimated microbial CP yield and feed efficiency were higher (P < 0.05) in the cows fed FTMR treatment but DM intake was lower (P < 0.05) in the cows fed the FTMR treatment than the cows fed the other treatments. The concentrations of rumen volatile fatty acids, except for butyrate, were highest (P < 0.0001) in cows fed the FTMR diet followed by cows fed TMR B and TMR A diets. The cows fed the FTMR diet had a higher molar proportion of acetate, total-tract apparent digestibility and ammonia-N concentration and a lower molar proportion of butyrate, organic matter, NDF, and ADF intakes than the cows fed the other diets. The cows fed the FTMR diet decreased fecal N excretion and retention N, increased the urea nitrogen concentration in the urine and milk and improved income over feed cost per cow per day compared with the cows fed the other diets. The results confirmed that FTMR prepared with WCGF and corn stover in combination replacing a portion of alfalfa hay is a suitable choice for improving lactation performance of dairy cows.

Influence of nutrient restriction on finishing Morada Nova lambs.

Our objective was to evaluate the effect of 15% crude protein (CP) and total digestible nutrient (TDN) restriction vis-á-vis that recommended by NRC (2007) on feed intake, digestibility, and average daily gain (ADG) of confined Morada Nova lambs. Twenty lambs with 18.8 ± 2.8kg liveweight were assigned to a randomized 2 × 2 factorial experiment with either early- or late-maturity feed formulation according to "Nutrient Requirements of Small Ruminants" with or without 15% CP and TDN restriction. The early-maturity diet, independent of restriction, resulted in greater dry matter and organic matter intake and increased rumination efficiency and feed conversion. Early-maturity diets also had the greatest nutrient digestibility as well as ADG and total gains. With late-maturity diets, independent of restriction, there were greater CP and TDN digestibilities as well as neutral detergent fiber (NDF) feed efficiency. However, when 15% of nutrients were restricted for late-maturity lamb diets, there was greater NDF intake and greater ether extract digestibility. Unrestricted early-maturity lamb diets was the better diet for confined Morada Nova lambs. Attention should be given to minimum effective NDF consumed and physically effective for this diet formulation. The use of late-maturity diets as recommended by NRC (2007) allows for 15% restriction of CP and TDN in Morada Nova lambs without negative effects on performance. This restriction should be tested in other tropical breeds to determine wider application.

The effects of feeding system and breed on the performance and meat quality of weaned lambs

Abstract Selecting proper animal genotype that suits particular environment, management systems, market requirements and food processing is a fundamental step to achieve efficiency in livestock operations. Thus, this study compared the performance and meat quality of the fat-tailed, Akkaraman (AKK) and crossbred, Anatolian Merino (AMR) lambs under the feeding systems of annual forage mixture (AFM), perennial pastures (PAS) or concentrated-based (CON). There were no consistent breed differences for liveweight gain (LWG) but AKK lambs that were fed AFM had greater NDF intake and digestibility than AMR lambs (P

Incorporating oldman saltbush hay and prickly pear in diets for red Sindhi calves

This study was designed to evaluate the nutrient intake, digestibility, degradability, and ruminal characteristics of Sindhi heifers fed diets that contained a combined total of 75% oldman saltbush hay (hereafter saltbush hay) and prickly pear cactus. Eight 12-month old intact male red Sindhi calves (four fistulated and four non-fistulated) with an initial mean weight of 170 ± 5 kg were assigned to 4 × 4 Latin squares, where factors consisted of four diets, namely 15% hay and 60% cactus; 30% hay and 45% cactus; 45% hay and 30% cactus; and 60% hay and 15% cactus, and four times at which rumen fluid was collected. Neutral detergent fibre (NDF) and acid detergent fibre (ADF) intakes in kg/day and NDF in percentage live weight (LW), water intake, salinity, and conductivity increased with hay level. Intake and digestibility of non-fibrous carbohydrates were curvilinear with higher values in diets containing 30% saltbush hay. The apparent digestibility of dry matter (DM) and organic matter decreased linearly as the concentration of saltbush hay increased in the diet. The pH of the rumen fluid was within the acceptable range for favourable microbial growth. The low temperature and high salinity and conductivity indices in the diets should be viewed with caution at higher concentrations of saltbush hay, because of a possible decrease in nutrient absorption and the development of health problems in the animals. Apparent degradability coefficients of DM and NDF were affected significantly by inclusion of prickly pear and saltbush hay in the diets.Keywords: animal nutrition, apparent digestibility, Atriplex nummularia Lindl, Opuntia ficus, ruminal degradation, semi-arid environment

Significance of Feeding Practices for Small Ruminants: A Reveiw

Current study was carried in order to understand the significance of feeding practices for small ruminants. In this regards a detailed review of already conducted researches was performance, whereby obtained facts were found to be much interesting and valuable. It was indicated that the profitable small ruminants farming depends upon feeding practices because the feed cost about 70% in farming. Small ruminants are often offered grazing on summer and winter fodders for maintenance and production requirements. However, commercial production demands a change in feeding practice with a trend for more efficient utilization of scarce feed resources. It was further stated that goats spent more time on eating than sheep, while ruminating time remain higher in sheep than goats. Drinking time appears different among these species. Goats spent more time on playing and resting than sheep. Moreover, in extensive, semi-intensive and intensive feeding systems, dry matter intake was noticed higher in sheep than goats. Crude protein intake was reported significantly higher in sheep than goats fed intensively. NDF and ADF intake was higher in goats than sheep. Average daily weight gain was higher in sheep than goats on the extensive system followed by the semi-intensive system. Feed efficiency was similar in both species, while the cost of gain per kg was more economical in goats compared sheep. In conclusion both species performed better on extensive feeding system than the other systems. It might be because of natural grazing behavior.

A simplified feeding system did not affect milk production compared with a total mixed ration system in dairy cows

The objective of our study was to compare animal performance of a simplified feeding system, named easy feeding (EF), with animal performance of a total mixed ration (TMR) feeding system, using high yielding dairy cows in early lactation. Two treatments, TMR (n = 16) and EF (n = 16), were evaluated in a completely randomised design. Holstein cows (617 ± 85.1 kg of body weight and 52 ± 16 days in milk) were used. The TMR treatment consisted of a mix of concentrates, corn silage and alfalfa hay, mixed and offered twice a day, while EF treatment involved the same diet components offered separately, with concentrate offered individually in the milking parlour, alfalfa hay offered as bales and corn silage offered straight from the silo bag, with no intervention of machinery in the feeding process. The feeding system had no effect on milk production, fat and protein yield, total net energy intake, total dry matter intake, body weight, body condition score plasma metabolites and eating and ruminating time. Cows in EF system had higher non-fibrous carbohydrates intake, lower intakes of crude protein and neutral detergent fibre and longer drinking time than cows in TMR system. Cows in EF selected a diet according to their preferences, which may have allowed them to achieved similar milk yield to TMR cows, despite the advantages of mixed diets in TMR treatment. Thus, the EF system is an attractive alternative to traditional TMR system, provided that costs of feeding operations are effectively reduced. Highlights A new simplified feeding system was compared to TMR system Milk production was similar in both feeding systems Simplified feeding system is an attractive alternative to traditional TMR systems, provided that costs of feeding operations are effectively reduced in EF

Balanced protein/energy supplementation plan for beef cattle on tropical pasture

The objective of this study was to evaluate the effects of the amount of balanced protein/energy supplement adjusted according to the protein content of the pasture on intake, digestibility, and performance of young bulls managed on tropical pasture. Thirty-six crossbred bulls (½ Angus × ½ Nellore) averaging 8 months of age and 217.2 ± 4 kg were distributed to eight 1-hectare paddocks with tropical grass. The treatments were based on the amounts of balanced protein/energy supplement (0, 2.8, 5.5 and 7.4 g/kg of body weight - BW). The amounts of supplement were chosen to achieve dietary protein levels of 110, 130 and 150 g/kg of dry matter (DM). The increase of supplementation had a positive linear pattern (P < 0.05) on intakes of DM, crude protein (CP), organic matter (OM), digestible organic matter (DOM) and CP:DOM ratio. However, the intakes of forage and neutral detergent fiber (NDF) did not change (P > 0.05) with supplementation. The apparent digestibility of DM, OM, CP and NDF were not affected (P > 0.05) by increasing supplement amounts. Conversely, the grazing time decreased linearly (P = 0.022) with increasing supplementation. Moreover, a linear increase in the final body weight (P = 0.002) and average daily gain (P = 0.002) and, a linear decrease in the efficiency of supplement use (P = 0.021) were observed with increasing supplementation. Increasing the amount of balanced protein/energy supplementation increases the DM intake, digestibility and animal performance with no substitution effect on forage intake.

Levels of substitution of corn by soybean hulls in high-concentrate diets for finishing beef heifers

We examined the production performance of Nellore heifers fed high-concentrate (90%) diets in which ground corn (GC) was substituted by ground soybean hulls (SH) at increasing levels (0, 33, 66, and 100%), in the concentrate portion. A total of 144 heifers (263.40 ± 13.90 kg average initial weight; 27 months old) received the test diets in a feedlot for 112 days. The experiment was set up as a completely randomised design with four treatments. Data were subjected to ANOVA and orthogonal contrasts, adopting ? = 5%. The sum of squares of treatments in the contrast analysis was decomposed into two orthogonal contrasts (L - linear and Q - quadratic effect) for the level of SH substituting GC. Dry matter intake was not changed by the GC substitution levels, averaging 2.51% of body weight. There was a linear increase in neutral detergent fibre intake (1.08, 2.03, 2.92, 3.78, 4.85 kg/day) and feed conversion (6.20, 7.08, 7.77, and 8.67 kg/kg); and a linear decrease in total digestible nutrient intake (5.78, 5.16, 5.03, 5.12, and 3.66 kg/day), average daily gain (1.24, 1.11, 1.02, and 0.89 kg/day), and slaughter weight (383.52, 374.71, 363.25, and 366.27 kg) as the substitution level was increased (0, 33, 66, and 100%, respectively). Subcutaneous fat thickness and loin-eye area were not influenced (P &gt; 0.05), averaging 5.30 mm and 53.09 cm2, respectively. Substituting ground corn by ground soybean hulls in high-concentrate diets determined a reduction in production performance of feedlot-finished Nellore heifers.

Consumption and ingestive behaviour of lambs fed varying levels of babassu mesocarp bran

Voluntary consumption (VolC) and ingestive behaviour (IB) of lambs fed diets containing different percentages (0.0; 7.5; 15.0 and 22.5%) of babassu mesocarp bran (I-BMB) were evaluated. The trial was at the Federal University of Tocantins, Campus de Araguaína-TO. Twenty lambs were evaluated using a completely randomized design, and five replications were performed. VolC data was obtained by measuring total volumes of both food supplied and food remaining after feeding. IB was evaluated throughout two, non-consecutive 24-h periods, with observations were recorded every five minutes that described the following behavioural variables: resting (REST), rumination (RUM), intake (INT) and chewing (CHEW). The particle size was also measured using a Penn State particle separator. All VolC parameters (dry matter intake, DMI; crude protein intake, CPI; neutral detergent fibre intake, NDFI; and acid detergent fibre intake, ADFI) increased linearly with I-BMB intake. I-BMB consumption did not interfere with water intake, nor did it affect I-BMB did not affect the duration of DMI, NDFI and ADFI. However, linear increases of rumination and chewing activities associated with DMI, NDFI and ADFI were observed as I-BMB levels increased. In summary, effects of inclusion I-BMB in diets of lambs included increased voluntary consumption, and reduced rumination and chewing, but not ingestion, efficiency. When economically favorable, these data suggest that inclusion of up to 22.5% I-BMB within balanced diets should be applied.

Substitution of wheat straw with sugarcane bagasse in low-forage diets fed to mid-lactation dairy cows: Milk production, digestibility, and chewing behavior

Sugarcane bagasse (SB) is a low-quality roughage source that is often plentiful during times of forage shortage. It is generally less costly compared with other conventional sources of forage. We hypothesized that SB could be used as a source of roughage for dairy cattle by replacing wheat straw (WS), another low-quality forage. This study evaluated the effects of replacing WS with SB in diets offered to mid-lactation dairy cows on milk production and fatty acid profile, intake, digestibility, chewing activity, and ruminal fermentation. Nine multiparous Holstein cows averaging (mean ± standard deviation) 105 ± 12 d in milk, 42.1 ± 2.9 kg of milk/d, and 617 ± 59 kg of body weight were used in a replicated 3 × 3 Latin square with 21-d periods. Treatments were (% of dietary dry matter, DM): (1) 0SB, diet containing 0% SB and 27% WS, (2) 9SB, diet containing 9% SB and 18% WS, and (3) 18SB, diet containing 18% SB and 9% WS. Sugarcane bagasse had greater organic matter (OM; 94.1 vs. 85.1% of DM), neutral detergent fiber (NDF; 86.2 vs. 76.4% of DM), acid detergent fiber (ADF; 62.9 vs. 45.2% of DM), and lignin (19.9 vs. 10.3% of DM) concentration, but less crude protein (CP; 2.63 vs. 3.72% of DM) concentration than WS. Sugarcane bagasse also had greater physically effective NDF (total dietary NDF multiplied by % of TMR on the 8-mm + 19-mm sieves, peNDF8; 63.2 vs. 40.6% of DM) and undegraded NDF after 288 h of incubation (uNDF288; 35.5 vs. 21.2% of DM) contents than WS. The undegraded NDF after 30 h of incubation (uNDF30) content was similar for all diets; however, peNDF8 concentration and proportion of long particles (retained on a 19-mm sieve) increased linearly as SB inclusion in the diets increased. Cows increasingly sorted against long particles as SB replaced WS. Intakes of DM (26.53 kg/d) and NDF (8.58 kg/d) did not differ among the treatments, but intakes of OM and CP decreased, whereas ADF and uNDF288 intakes increased with SB inclusion level. Total-tract digestibilities of OM, CP, and NDF decreased linearly as SB replaced WS. Milk yield (37.0 kg/d), energy-corrected milk yield (ECM; 38.2 kg/d), feed efficiency (1.44 kg ECM yield/kg DM intake), and milk composition (fat, 3.89%; true protein, 2.90%) did not differ among diets. Increasing SB concentration of the diet linearly increased rumination time, but ruminal pH (ruminocentesis, 4 h after feeding) decreased. Total volatile fatty acid concentration increased linearly, whereas acetate:propionate decreased linearly, as SB replaced WS. The results indicate that replacement of WS with increasing levels of SB in low-forage diets with similar uNDF30 concentrations did not affect performance of mid-lactation dairy cows. We conclude that SB can be used as a fiber source in diets fed to dairy cows in mid-lactation; however, the decrease in total-tract digestibility of diets may decrease lactational performance when fed to high-producing dairy cows.

Characteristics of Nutrition, Growth, Carcass and Meat of Male Goats Fed Babassu Mesocarp Flour

Twenty-eight Boer × Saanen castrated male goats (21.6 ± 3.0 kg of initial body weigh) were distributed in a randomized complete block design to evaluate the effects of increasing levels (0, 100, 200 or 300 g/kg, in dry matter basis) of dietary babassu mesocarp flour (BMF) on performance, nutrient digestibility, carcass characteristics, and meat physical and chemical composition. When significant treatment effects were found, data were submitted to orthogonal polynomials for treatment responses. BMF did not change the intake and digestibility of dry matter and crude protein. However, it increased linearly the total carbohydrates intake (p = 0.013), neutral detergent fiber intake (p &lt; 0.001) and digestibility (p = 0.027), while it decreased linearly the intake of non-fibrous carbohydrates (p &lt; 0.001) and ether extract (p &lt; 0.001), without changing their digestibility (p &gt; 0.05). The dressing percentage (p = 0.003) and rib eye area (p = 0.024) had a quadratic effect with increasing levels of BMF. The total gastrointestinal weight (TGI) had an increased linear effect (p = 0.001), while the proportion of rumen (p = 0.010), omasum (p &lt; 0.001) and abomasum (p = 0.001) increased linearly with BMF addition. The same effects were presented in leg weight (p = 0.045) and muscle weight (p = 0.049). Weight and yields of commercial cuts and meat physicochemical composition did not change (p &gt; 0.05) with inclusion levels of BMF. The addition of babassu mesocarp flour up to 200 g/kg in the diet of male goat can improve the dressing percentage without major changes in meat physical and chemical traits, representing an attractive alternative feed.

Ingestive behaviour and performance of feedlot lambs fed saccharine sorghum and corn silages

This study evaluated the ingestive behaviour and performance of feedlot lambs fed saccharine sorghum and corn silages. Ten animals were randomly selected from a group of 32 uncastrated male Suffolk lambs. The four treatments consisted of diets with 50% of silage made from forage sorghum (BD 1615), two varieties of saccharine sorghum (BRS 506 and BRS 511), and corn (BRS 2223). Ingestive behaviour was observed by a scan sampling method using seven strategically positioned video cameras so as not to interfere with the usual animal behaviour. The animals were observed for three 48-hour periods at 15-day intervals, with a total of 144 hours of observation. Video recordings were then examined to identify the time spent in ruminating, eating, drinking water and idling. Times spent feeding or drinking water were not significantly affected by the treatments. Animals fed forage sorghum silage had higher neutral detergent fibre (NDF) intake (0.41 kg of NDF), thus spent more time ruminating (342 min/day). Rumination time was similar for the BD 1615 and BRS 506 silages and was 85 min/day greater than for the BRS 511 and BRS 2223 silages, which were similar. Average daily gain was greater for BRS 2223 (275 g/day) than for BRS 506 and BRS 511 silages, which were similar (196 g/day). Ingestive behaviour for BRS 511 was similar to that observed for BRS 2223. Ingestive behaviour for BRS 506 was similar to that observed for BD 1615. Average daily gain was related to intake and ruminating efficiency.&#x0D; Keywords: eating, idling, roughage, rumination, sheep (Ovis aires)

Replacement of soybean meal with levels of inclusion of soya waste in the diet of growing goats.

An experiment was conducted to investigate the effect of replacing soybean meal with soya waste at different levels on intake, digestibility and growth in goats. Eighteen male goat kids with initial body weight (BW) of 13.0kg were distributed equally to three dietary groups. They were fed Napier grass (Pennisetum purpureum) and concentrate mixture, and each goat was assigned to an individual pen. Soybean meal in the concentrate mixture was replaced with soya waste at 0% (T1), 50% (T2) and 100% (T3) levels in respective dietary groups. These diets were isocaloric and isonitrogenous. Results showed that animals fed T3 diet exhibited higher Napier grass intake than those fed T1 or T2 diet. There was no influence on total intakes of dry matter (DM), organic matter (OM), crude protein (CP), metabolic BW, per cent BW and metabolisable energy by the dietary groups. However, there was an increasing trend on intake and digestibility of neutral detergent fibre (NDF) with increasing levels of soya waste in the diets. Animals fed T3 diet showed higher intake and digestibility of NDF than those fed T1 diet. There was no influence of the dietary groups on digestibilities of DM, OM and CP. Similarly, there was no effect of them on the final BW, total BW gain, daily BW gain, feed conversion ratio and feed cost. Soya waste can replace 100% soybean meal in diets for growing goats, because no change was observed in nutrient intake, digestibility and growth performance; inclusion of soya waste enhanced the intake and digestibility of NDF.

Cultivated Pastures Affect Nutrient Intake and Feeding Behavior of Sheep

Cultivated pastures may increase the meat production of sheep, but it is necessary to understand the plant-animal relationships in a pastoral environment. This study aimed to assess the effect of forage cultivars on the intake and feeding behavior of sheep. Four treatments were evaluated, consisted of the cultivars Panicum maximum cvs. Aruana and Massai and Brachiaria brizantha cvs. Marandu and Piata. Twenty-four sheep, male of the Santa Ines genotype, were used with six replications per treatment. Daily forage and nutrient intakes were evaluated in addition to time in grazing, rumination, and leisure activities. The animals in the pasture of Aruana grass demanded the most extended times of grazing and rumination (p<0.05). The leisure time was higher (p<0.05) in the animals kept in pastures of Piata grass. The highest intakes of dry matter and crude protein in g/day (p<0.05) were found in the animals kept in the pasture of Marandu grass, and a smaller intake was found in the animals kept in the pasture of Massai grass. Intake of leaf blades was higher (p<0.05) in the animals kept in pastures of Massai and Marandu. The neutral detergent fiber intake did not differ among the cultivars. It is concluded that pasture structure and chemical composition of tropical forage cultivars influence the nutrient intake and feeding behavior of sheep. The low leaf blade offer of the pasture of the Aruana grass negatively affects the feeding behavior of the sheep, but the crude protein in forage of this cultivar favors the nutrient intake, feed conversion, and performance of sheep.

Apparent total tract digestibility, ruminal fermentation, and blood metabolites in beef steers fed green-chopped cool-season forages.

An experiment was conducted during the winter of two consecutive years to evaluate the effects of feeding green-chopped cool-season forages on digestibility, ruminal fermentation, and blood parameters in beef steers. Nine ruminally cannulated Angus crossbred steers (year 1: 359 ± 79 kg; year 2: 481 ± 105 kg) received ad libitum green-chopped forages from pastures planted with one of the following mixtures: 1) OAT = Horizon 201 oats (Avena sativa L.)/Prine annual ryegrass (Lolium multiflorum Lam.) at 95 and 17 kg/ha, respectively; 2) RYE = FL401 cereal rye (Secale cereale L.)/Prine annual ryegrass (Lolium multiflorum Lam.) at 78 and 17 kg/ha, respectively; or 3) TRIT = Trical 342 triticale (X Triticosecale spp.)/Prine annual ryegrass (Lolium multiflorum Lam.) at 95 and 17 kg/ha, respectively. Intake was measured using the GrowSafe system and orts were discarded prior to subsequent feeding. After a 14-d adaptation, feed and fecal samples were collected twice daily for 4 d to determine apparent total tract nutrient digestibility using indigestible neutral detergent fiber (NDF) as an internal marker. On day 19, blood and ruminal fluid samples were collected every 3 h during a 24-h period to analyze plasma urea nitrogen (PUN) and glucose, ruminal pH, and concentration of ruminal ammonia nitrogen (NH3-N) and volatile fatty acids (VFA). Data were analyzed as a generalized randomized block design with repeated measures using the PROC MIX of SAS. No effect of treatment (P > 0.05) was observed for intake of dry matter, organic matter (OM), crude protein, NDF, or acid detergent fiber. Apparent total tract digestibility of nutrients was greater (P < 0.05) for OAT and TRIT when compared with RYE, with OM digestibility being 82.7%, 79.6%, and 69.5%, respectively. An effect of time (P < 0.01) was observed for ruminal pH. Plasma concentration of glucose was greater (P < 0.01) in steers consuming OAT, whereas steers fed RYE had greater (P < 0.05) concentrations of ruminal NH3-N and PUN, and the least concentration of total ruminal VFA (P < 0.05), despite having the greatest (P > 0.05) molar proportion of acetate, branched-chain VFA, and acetate:propionate. Increased nutrient digestibility and favorable ruminal fermentation and blood metabolites of OAT and TRIT are potentially conducive to enhanced growth performance when compared with RYE.

Increasing the content of physically effective fiber in high-concentrate diets fed to beef heifers affects intake, sorting behavior, time spent ruminating, and rumen pH.

AbstractThe importance of fiber particle size in ruminal health is well known, but there are fewer studies to assess the requirements of physically effective NDF (peNDF) in beef cattle than in dairy cattle. The objective of this study was to establish the optimal peNDF proportion in high-concentrate diets fed to beef cattle, to reduce the risk of subacute ruminal acidosis. The experimental design was a replicated Latin Square 4 × 4, with four periods of 21 d. Treatments consisted of four diets with different peNDF proportions: 6.4%, 10.4%, 13.6%, and 15.4%, offered ad libitum as total mixed ration, and containing 15% barley straw and 85% concentrate. Diets, which differed in proportions of straw > 4 mm (considered peNDF) and straw < 4 mm, were manually mixed with concentrate. This concentrate was the same for all diets. A ruminal bolus was orally administered to each heifer for pH measurement. Intake, water consumption, intake by particle size, feed sorting, feeding behavior, behavioral activities, and rumen pH were recorded. Chemical composition and particle sizes of diets offered were assessed in the last week of each period. Data were analyzed using the MIXED procedure of SAS. Orthogonal contrasts determined the linear and quadratic effects of increasing peNDF proportion. T-test procedure determined whether heifers carried out sorting behavior. Particles >4 mm linearly increased (P = 0.001), and particles <4 mm linearly decreased (P = 0.001) as peNDF increased. Water consumption and feeding behavior were unaffected by treatment. As peNDF increased, intakes of DM and NDF linearly decreased (P = 0.001), whereas peNDF intake increased (P = 0.001). Intake of particles > 4 mm linearly increased, whereas intake of particles < 4 mm linearly decreased (P = 0.001) as peNDF increased. Diet 6.4% performed sorting for particles > 4 mm (P < 0.01), and diets 13.6% and 15.4% against particles > 4 mm (P < 0.01). Diet 10.4% tended to sort against particles > 4 mm (P < 0.10). Time spent ruminating linearly increased (P = 0.001) as peNDF increased. Diets did not differ in mean and minimum rumen pH, but time under rumen pH thresholds (5.8, 5.7, 5.6, and 5.5) linearly decreased as peNDF increased (P < 0.05). The results suggested that the diet that best met the requirements of not compromising intake, limiting sorting behavior, and promoting time spent ruminating to reduce the number of hours under rumen pH thresholds, was the 10.4% diet.

Performance and milk composition of Holstein cows fed with dried malt bagasse and selenium-enriched Saccharomyces cerevisiae

• Addition of selenized Saccharomyces cerevisiae did not improve fiber digestibility. • Use of selenium-enriched yeast increased the milk selenium concentration. • Use of selenium-enriched yeast had no effect oxidative stability of the milk. • Inclusion of malt bagasse reduced energy intake and microbial protein synthesis. • Inclusion of 24% dried malt bagasse reduced energy-corrected milk production. The objective of this study was to evaluate the effect of selenium-enriched Saccharomyces cerevisiae on the performance, composition and quality of milk from cows fed diets containing dried malt bagasse. Eight Holstein cows were distributed in a 4 × 4 double Latin square. The treatments were in a 2 × 2 factorial scheme: with or without the inclusion of malt bagasse x with or without the addition of selenium-enriched Saccharomyces cerevisiae . Dried malt bagasse was included at 24% in the dry matter (DM) of the diet; the amount of yeast supplied was 15 g/day and was composed of strain Saccharomyces cerevisiae CNCM I-1077 containing 1.0 × 10 9 CFU/g and 170 mg selenium/kg. Cows fed diets containing malt bagasse presented lower intakes of DM, crude protein and non-fibrous carbohydrates (NFC) and higher intakes of ethereal extract and neutral detergent fiber (P < 0.05). The digestibility of DM and the NFC of the diets with malt bagasse were lower in relation to the diets without this ingredient (P < 0.01). The addition of yeast did not influence the intake and digestibility of nutrients or any blood parameters. The levels of cholesterol and triglycerides of cows fed malt bagasse were higher than those that did not receive this by-product (P < 0.01). There was an interaction for blood urea, wherein the concentrations of the malt bagasse diet were higher than the diets without bagasse and without bagasse with yeast (P < 0.05). Cows fed diets without malt bagasse and with yeast produced more microbial protein than those fed with malt bagasse and yeast (P < 0.05). The use of selenium-enriched Saccharomyces cerevisiae had no effect on the production, composition and oxidative stability of the milk, but increased the milk selenium concentration (P < 0.05). The inclusion of malt bagasse reduced energy-corrected milk production, fat, protein, casein and total solids content of milk (P < 0.05), and increased milk urea nitrogen and the conjugated diene concentration (P < 0.01). Thus, the use of selenium-enriched Saccharomyces cerevisiae in the diet of lactating cows increased the selenium concentration, but did not improve the production and oxidative stability of the milk, whereas the inclusion of dried malt bagasse reduced energy intake, energy-corrected milk production and the milk fat and protein contents.

Enteric methane emissions in crossbred heifers fed a basal ration of low-quality tropical grass supplemented with different nitrogen sources

The aim of the present study was to assess enteric methane (CH&lt;sub&gt;4&lt;/sub&gt;) emissions by crossbred heifers fed a basal ration of low-quality tropical grass supplemented with different nitrogen sources. Four crossbred heifers (Bos taurus × Bos indicus) with an average live weight (LW) of 355 ± 6.01 kg were used in a 4 × 4 crossover Latin square design with four periods of fifteen days each. Basal ration was chopped low-quality tropical grass Pennisetum purpureum fed to cover ~70% of metabolizable energy requirements for maintenance of heifers and it was supplemented with either poultry litter (control ration, T1), urea (T2), canola meal (T3) or soybean meal (T4). Enteric CH&lt;sub&gt;4&lt;/sub&gt; emissions of heifers were measured in open-circuit respiration chambers for 23 hours. Dry matter (DM), neutral detergent fibre (NDF) and acid detergent fibre (ADF) intakes decreased when feeding urea (1.6% of ration) as a source of nitrogen (7.64, 3.78, and 1.83 kg/d, respectively). Rations including urea (T2) or canola meal (T3) given to heifers fed a basal ration of low-quality Pennisetum purpureum grass significantly reduced acetic acid concentration and increased propionic acid concentration in the rumen and decreased the loss of gross energy as methane (P = 0.004). Incorporation of urea or canola meal in the ration of cattle fed low-quality tropical grass can decrease methane emissions and improve rumen fermentation patterns.

Effect of dietary probiotics supplementation on intake and production performance of ewes fed Atriplex hay-based diet

The present study was carried out to evaluate the effects of probiotics on intake, performance, rumen fermentation and blood metabolites of Barki ewes fed Atriplex hay based diet. Thirty pregnant Barki ewes with an average initial body weight (BW) of 45.5 ± 0.98 kg, were blocked according to lambing date and BW into three experimental groups. The treatments were: (1) control diet, (2) control diet + 2 g Saccharomyces cerevisiae (2 × 1010 CFU) per day and (3) control diet + 2 g Bacillus subtilis (1.0 × 1011 CFU/kg) and Lactobacillus casei (1 × 1010 CFU/kg) per day. Probiotics inclusion increased dry matter, organic matter, crude protein and neutral detergent fiber intakes (P < 0.05) but did not affect body weight, milk yield, milk composition or efficiency (milk/dry matter intake). The bacteria diet increased average daily weight gain of lambs (P < 0.05) compared to the yeast and control diets. Compared with the control, the probiotic diets increased (P < 0.05) ruminal ammonia-N concentration. The pH and total volatile fatty acids concentration were not influenced by probiotic supplementation. Blood urea nitrogen was increased (P < 0.05) and total lipids and triglycerides were decreased (P < 0.05) with probiotics supplementation. All the other blood parameters were not affected. The present study demonstrated that supplementing ewes fed Atriplex hay based diets with probiotic bacteria resulted in higher weaning weight, average daily weight gain and improved health status in lambs.