Levels Of Neutral Detergent Fiber Research Articles

The effects of diets containing two corn stubble levels and three non-hydrogenated lipids sources on fattening performance, carcase, and meat quality of male hair-lambs

Research regarding the association of fatty acids (FA) with corn stubble in feedlot lambs is limited. FA dietary supplements can reduce the digestibility of neutral detergent fibre (NDF). However, it is not known if the NDF amount added with corn stubble and FA source in the diet can influence the content of polyunsaturated fatty acids (PUFA) and the conjugated linoleic acid (CLA), all of which are related to meat quality. In this study, 96 male-lambs (29 ± 4.9 kg) were assigned in two dietary NDF levels [25% (NDF-25) and 29% (NDF-29)] and four supplemental fat treatments [no supplemental (C), 3% CLA-60, 3% Safflower oil (SAF) and 3% linseed oil (LIN)] evaluated in a 2 × 4 factorial arrangement of treatments. Compared with CLA diets, diets supplemented with SAF and LIN contained more C18:2. Dietary forage level did not affect average daily gain, feed efficiency, or carcase characteristics (p = .56). With NDF-29 increased meat protein content (2%, p < .05). Meat chromatic b* values were greater (p = .02) with NDF-25. Control vs. supplemental lipids (SL) MUFA and PUFA increased in the muscle with SL. The endogenous level of CLA in muscle improved (p < .05) in the muscle with SL. Juiciness meat increased with both NDF levels and lipid supplements (p = .06). In conclusion, protein content and juiciness in the meat improve with NDF-29 (as corn stubble) on a diet. Similarly, SAF and LIN increase the content of PUFA and CLA in meat. Highlights A slight increase of NDF from 25% to 29% added with corn stubble within an iso-energetic diet, change the colour and some sensory variables of the lamb meat. Safflower and linseed oils included in the diet at 3% improve the content of conjugated linoleic acid in lamb meat. The General Quality index in the meat sensory analysis is not affected by inclusion levels of fibre (NDF 25 vs. 29) and lipids (3%) in the diet of hair lambs.

Effect of level of dietary neutral detergent fibre on the ultrastructure of M cells and mucosa integrity in rabbits’ appendix

Membranous (M) cells are believed to special gateways of the mucosal immune system because of sampling antigens from the gut lumen. However, little is known regarding the effect of diets on regulating M cells. So, we examined the ultrastructural characteristics of microfold (M) cells in rabbits fed different dietary fibre-to-starch ratios (I: 2.3, II: 1.9, III: 1.4, and IV: 1.0). Appendix tissues were obtained from rabbits at 52, 62, 72, and 82 d. Diet I had higher M cell area than diet IV (p < .01) during total experiment. Using electron microscope, we observed apparently intestinal damage and M cells apoptosis in diet I and IV compared to diet II and III (p < .001), except for 62d. By estimation of M cell deviations from normal structure and TNF-a mRNA expression in appendix from different diet treatments, it is apparent that degree of deviations from normal structure in diet I, IV was higher than diet II, III, except for 62 days. The appendix TNF-a mRNA levels were significantly (p < .01) increased in diet I, IV at 52, 62, 72, 82 days compared to diet II, III. These data elucidated that an imbalance dietary fibre-to-starch ratio induced the structural damage of M cell. Highlights High fibre diet can increase M cell area compared to low fibre diet for rabbits. High fibre or starch diets caused rabbits’ appendix mucosal damage and M cell apoptosis. High fibre or starch diets significantly increased the appendix TNF-A mRNA levels.

ASSESSMENT OF CONTENTS OF STRUCTURAL CARBOHYDRATES AND LIGNIN OF PERENNIAL FODDER HERBAGES DEPENDING ON VEGETATIVE STAGE GROWTH

The purpose of this study is to evaluate cereal grasses – Bromus inermis, Festuca pratensis, Phleum pratense, and legumes: Trifolium pratense, Medicago varia in terms of their content of acid-detergent fibre (ADF), neutral detergent fibre (NDF), acid-detergent lignin (ADL) and hemicellulose (HC), cellulose depending on phases of vegetation – grasses: at vegetative, earing and flowering; legumes– vegetative. It was found that as the herbs grow, an increase in all fractions of the cell walls of leguminous herbs is observed, the cell walls occupy a smaller fraction of dry matter than in grasses, due to the lower HC content in them –10-12%, compared with 25-30% in grasses. The contents of ADF, NDF and ADL (% of dry matter) in grasses prior earing are 31-31, 50-55, 4-6: in earing – 32-37, 55-65, 5-6; in flowering – 40-45, 65-70 and 70-72, 7-9, respectively. Legumes have a higher content of ADL. As plants grow, the relative proportion of ADF in NDF increases, but it does not exceed 50% in grasses. In legumes – 70-80% regardless of the growth phase, explains the lower digestibility of legumes than grasses. To judge the levels of ADF and NDF in herbs, depending on the content of crude fibre (CF), the corresponding regression equations were calculated for grasses and feed prepared from them. The relationship between CF and ADF was closer (n = 64, s = 2.4%, r = 0.93) than between CF and ADL (n = 64, s = 4.4%, r = 0.87). Based on these studies and generalisation of the literature data, ADF and NDF in hay and haylage standard are recommended.

Replacing soybean hulls with grass hay on growth, intake, total tract digestibility, and rumen microbial nitrogen production of weaned Holstein dairy calves from 8 to 16 weeks of age

The objective of this experiment was to determine the effects of replacing soybean hull (SBH) pellets with grass hay (GH) on growth, intake, total-tract digestibility, and rumen microbial nitrogen production of weaned dairy calves from 8 to 16 wk of age. Holstein calves (n = 16) were randomly assigned to 1 of 4 rations containing, on a dry matter (DM) basis, 76% grower with the remaining 24% being made up of different amounts of SBH pellets and GH [0% GH, 24% SBH (0GH); 8% GH, 16% SBH (8GH); 16% GH, 8% SBH (16GH); and 24% GH, 0% SBH (24GH)]. Calves were weaned at 6 wk, housed individually, and studied from 8 to 16 wk of age. From 8 to 9 wk of age calves were offered a ration consisting of 50% of texturized starter (20% CP and 35% starch), which was offered from 3 d of age, and 50% of their assigned ration. From 9 wk until the end of the study, calves were offered 100% of their assigned ration. Intake and body weight were measured weekly, and frame measurements were taken at the beginning and end of the study. Animal behavior observations were recorded every 5 min over a 24-h period at 10 and 14 wk of age. Total fecal and urine collection was conducted for 4 d consecutively at 11 and 15 wk of age. Feed and feces were evaluated for DM, N, neutral detergent fiber, acid detergent fiber, and starch to determine total-tract digestibility. Feces were evaluated for geometric mean particle length (Xgm) and particle size distribution. Urine was evaluated for N, creatinine, urea, and total purine derivatives to estimate microbial N yield. Calves offered 0GH and 8GH had a 20% increase in intake, average daily gain (1.23, 1.27, 0.89, and 0.71 kg/d for 0GH, 8GH, 16GH, and 24GH, respectively), and feed efficiency compared with 16GH and 24GH. Calves offered 8GH had the greatest levels of neutral detergent fiber and acid detergent fiber digestibility, as well as the greatest estimated microbial N yields. Inclusion of forage increased rumination time (2.75, 6.89, 7.18, and 8.16 h/d for 0GH, 8GH, 16GH, and 24GH, respectively) and decreased fecal Xgm by ~35% compared with calves offered 0GH. In the current study, increasing the replacement of SBH with GH beyond 8% was detrimental to weaned calf performance. These results indicate that when diets containing 8% GH and 16% SBH were fed to recently weaned calves, rumen functionality and feed efficiency were optimized compared with the other GH-SBH combinations.

Effect of source and level of forage in the diet on in vitro ammonia emission from manure of Holstein and Jersey dairy cows

Reducing overall reactive N losses from dairy production systems depends substantially on reducing the atmospheric emission of manure ammonia (NH3). The objective of this study was to determine potential NH3-N emission of reconstituted manure using an in vitro protocol. Feces and urine were collected from a companion study designed as a Latin square in which 4 Holstein and 4 Jersey cows were fed diets containing 2 levels of forage neutral detergent fiber (NDF) [low-forage NDF (19%) vs. high-forage NDF (24%; dry matter basis)] from either alfalfa silage or corn silage (70:30 vs. 30:70 ratio of alfalfa silage NDF:corn silage NDF) arranged as a 2 × 2 factorial. All diets contained similar levels of crude protein (17%) and starch (23%), and had forage-to-concentrate ratios of 55:45 and 68:32 for low- and high-forage NDF diets, respectively. Measurements of NH3-N emission were conducted in a laboratory-scale chamber with 16 g of reconstituted manure (urine plus feces) incubated for 48 h at 15°C with sampling at 1, 3, 6, 12, 24, 36, and 48 h. Hourly NH3-N emissions data were analyzed using a repeated-measures mixed model in R (https://www.r-project.org/). The fixed effects were breed, forage NDF level, forage NDF source, time of sampling, and all possible interactions; cow was included as a random term. The cumulative 48-h NH3-N emissions and the scaled-up emissions accounting for daily output of manure from each cow were analyzed using the same model but without time of sampling. Level and source of forage in the diet tended to influence the pattern in hourly rate and 48-h cumulative emission, respectively. Accounting for daily manure volume differences, low-forage NDF diets led to lower estimates of daily NH3-N emissions than high-forage NDF diets (20% on a cow basis, 15% on a raw manure basis, and 18% on a manure-N basis). Compared with Holsteins, Jerseys emitted 17% lower estimated NH3-N on a cow basis, mainly due to lower manure excretion but tended to emit 15% more NH3-N expressed on a manure-N basis. Findings of this study suggested that cow breed and dietary forage NDF level should be considered in the prediction of NH3-N emission from the dairy industry.

Forage yield and nutritive value of hay from sorghum-sudangrass hybrids

The objective was to evaluate agronomically nine sorghum-sudangrass hybrids (Sorghum bicolor × Sorghum sudanense) and the nutritive value of their respective hays. The experimental design used was randomized blocks in a 3 × 9 factorial scheme, with three replications. Three cuts were made: 42 days after germination, 29 days after regrowth, and 28 days after the second regrowth. All hybrids showed a higher number of plants ha–1 (P &lt; 0.05) in the second cut. For the green matter and dry matter production of the hays, the values ranged from 49.16 to 62.07 t ha–1 and 9.07 to 11.43 t ha–1, respectively. There were no differences (P &gt; 0.05) in dry matter, mineral matter, or ether extract. The hybrids 1013020, BRS 810, 1013016, and 1624F016 showed higher values of crude protein (CP) of 16.49, 16.17, 16.08, and 15.88%, respectively. Differences were observed (P &lt; 0.05) in neutral detergent fiber (NDF) content. The hybrids 1013020, BRS 802, 1013021, 1013016, BRS 810, and 1624F006 presented lower levels of NDF (60.57, 60.74, 62.15, 62.37, 62.58, and 64.70%, respectively). The hybrids BRS 802, 1013016, BRS 810, and 1624F006, stood out above the others, presenting high forage yield and adequate nutritive value (CP content &gt;13% and NDF content &lt;65%).

73 Effects of dietary neutral detergent fiber and standardized ileal digestible lysine levels on growth performance and carcass characteristics of growing-finishing pigs

Abstract Our objective was to determine the effects of feeding different neutral detergent fiber (NDF) and standardized ileal digestible (SID) lysine (Lys) levels on performance of growing-finishing pigs from 30- to 130-kg. A total of 2,016 barrows and gilts (PIC 280×Camborough, initial BW of 29.6±0.53 kg) were allotted to a randomized complete block design with a 2×2 factorial arrangement. Dietary treatments (Table 1) consisted with two NDF levels (13% or 20%) and two SID Lys curves (PIC2008 or PIC2016). There were 21 mixed-sex pigs per pen, and 24 pens per treatment. The experiment diets were fed in 3 phases. Wheat, wheat by-products, peas, and canola oil were used with NRC (2012) loading values to achieve treatments, and all diets were formulated to be iso-caloric (2,420 kcal NE/kg). Experimental data were analyzed using generalized linear mixed models with pen as the experimental unit. Increasing NDF level resulted in a reduction (P&amp;lt; 0.05) in average daily gain (ADG), average daily feed intake, hot carcass weight, carcass yield, carcass ADG, and backfat depth (Table 2), and tended to decrease percentage of removals and mortality (P=0.10). Pigs fed PIC2016 Lys curve had greater ADG and carcass ADG as compared to those fed PIC2008 Lys curve (P&amp;lt; 0.05). There were NDF×Lys interactions (P&amp;lt; 0.10) for ADG, gain to feed ratio (G:F), carcass ADG, and carcass G:F. These response criteria were improved for pigs fed PIC2016 Lys curve compared to those fed PIC2008 Lys curve when NDF level was 13%; while no evidence of differences was observed at 20% NDF. Results indicate that increasing NDF level from 13 to 20% deteriorate performance of 30- to 130- kg pigs; and the improved growth performance of pigs fed PIC2016 Lys curve as compared to those fed PIC2008 Lys curve was only observed when lower NDF level was presented.

79 Effects of dietary net energy and neutral detergent fiber levels on growth performance and carcass characteristics of growing finishing pigs

Abstract Our objective was to determine the effects of feeding different net energy (NE) and neutral detergent fiber (NDF) on performance of growing-finishing pigs from 30- to 135-kg. A total of 2,058 barrows and gilts (PIC 380×Camborough, initial BW 33.4±0.60 kg) were used in a 97-d growth trial with 21 pigs per pen and 14 pens per treatment in a randomized complete block design. Treatments were formulated to contain 2.11, 2.21, 2.32, 2.42, 2.53, 2.63, and 2.73 Mcal NE/kg; and 24.2, 19.7, 15.1, 10.6, 10.2, 9.8, and 9.5% NDF throughout the experiment. Wheat, wheat byproducts, barley, rye, peas, fababeans, and canola oil were used with NRC (2012) loading values to achieve the treatments. Dietary lysine levels were set to meet PIC2016 lysine requirements for finishing gilts. Experimental data were analyzed using generalized linear mixed models and linear and quadratic polynomial contrasts were built with pen as the experimental unit. Increasing NE or decreasing NDF improved (linear and quadratic, P&amp;lt; 0.05) average daily gain (ADG), gain-to-feed ratio (G:F), carcass ADG, and carcass G:F (Table 1); but reduced (linear and quadratic, P&amp;lt; 0.05) average daily feed intake (ADFI). Comparing to pigs fed 2.42 Mcal/kg diet (energy equivalent to a corn-soybean meal diet), even though those fed 2.11 Mcal/kg diet had 8.7% increment on ADFI, daily NE intake was still 5.4% less. Hot carcass weight, backfat depth, and carcass yield increased (linear and quadratic, P&amp;lt; 0.05) and lean yield decreased (linear and quadratic, P&amp;lt; 0.05) with increasing dietary NE and decreasing NDF. No evidence for differences (P &amp;gt;0.10) were observed for loin depth. Removal and mortality rate was reduced (quadratic, P&amp;lt; 0.05) with increasing dietary NE and decreasing dietary NDF. In summary, increasing dietary NE while reducing dietary NDF resulted in improvements on growth performance, carcass characteristics, and removal and mortality rate.

209 Appropriation of feedlot rations’ nutrient levels of imported cattle in central region of Turkey

Abstract An experiment was conducted to determine the nutrient contents of concentrated feed and Total Mixed Ration (TMR) samples taken from 6 feedlot farms in Kirikkale province and their compensation of bulls’ requirements. In the province, 6 farms active in the feedlot business were identified, and their manufactured feed and TMR samples were taken at 15-day intervals, starting from cattle received either from Europe or South America. For all periods, in each sample, crude fat (EE), crude protein (CP), crude ash (CA), crude cellulose (CS), dry matter (DM), acid detergent fiber (ADF) and neutral detergent fiber (NDF) levels were determined based on Association of Official Analytical Chemists (AOAC) methods. Metabolizable Energy levels of Total Mixed Rations (TMR) and concentrate part of feeds were calculated based on Turkish Standard Institute (TSE) method. The determined values were evaluated according to animal numbers (herd size) in feedlot and fattening periods. It was determined whether the size of the feedlot farm has an effect on TMR preparation and the nutrients in TMR are matching with the beef cattle requirements during the fattening period. Data was analyzed by using one-way ANOVA and means were separated by using LSD. Results showed that CP levels of the TMRs were significantly higher than the requirements listed in Nutrient Requirements of Beef Cattle published by National Research Council (NRC) in both cattle receiving fattening periods (0–45 days and 45–90 days) (P &amp;lt; 0,05). Additionally, cattle feeders fed their cattle with similar protein levels independent from the size of feedlot (P &amp;gt; 0,05), unexpectedly. Although it was compared with requirements, energy levels were similar in all feedlots (P &amp;gt; 0,05). All determined nutrients levels of concentrate parts of TMRs in large and small herds were similar (P &amp;gt; 0,05). In conclusion, considering that this situation absolutely increases cost of fattening and may cause metabolic diseases.

PSVII-11 Fecal parameters as indicators of starch digestibility and feedlot performance of water buffaloes

Abstract This study evaluated fecal parameters indicative of starch digestibility of water buffaloes (Bubalus bubalis) of three genetic groups (GG: Jafarabadi, Mediterranean, and Murrah). Seventy-eight non-castrated males [n = 26 of each GG; 200 kg of initial body weight (BW); 210 days of age] were used. Animals were finished in feedlot, receiving a diet rich in starch [38.76% in dry matter (DM) basis]. Samples of feces, diet offered, and orts were collected for digestibility test during 3 consecutive days. Diet samples were incubated in situ in the rumen of cannulated buffaloes. The remaining material was submitted to analysis to quantify the indigestible neutral detergent fiber levels. Fecal starch (FS) determination was performed by near infrared reflectance spectroscopy. Final BW (BW, kg), metabolic BW (BW0.75, kg0.75), average daily gain (ADG, kg/day), DM intake (DMI, in kg/day, and %BW) were recorded. Data were analyzed using MIXED and CORR procedure in SAS, with significance considered if P ≤ 0.05. Starch digestibility and FS concentration are not influenced by GG (P ≥ 0.23), unlike fecal DM and fecal pH (P ≤ 0.04; Table 1). Although weak, negative correlations were detected between FS and BW (r = -0.247; P = 0.05) and BW0.75 (r = -0.261; P =0.03), as well as between fecal DM and BW (r = -0.245; P = 0.05), ADG (r = -0.341; P &amp;lt; 0.01), DMI, kg/day (r = -0.374; P &amp;lt; 0.01), and DMI, %BW (r = -0.335; P &amp;lt; 0.01) variables. The results demonstrate that there are differences among GG of water buffaloes regarding fecal parameters. Furthermore, the high FS content and the low fecal pH may indicate the low capacity of water buffaloes to digest starch. Thus, the research results provide evidence that water buffaloes are not able to use high-grain diets, and fecal parameters proved to be potential tools to evaluate the feedlot performance of these animals.

Replacing Forage by Crude Olive Cake in a Dairy Sheep Diet: Effects on Ruminal Fermentation and Microbial Populations in Rusitec Fermenters.

Simple SummaryLarge amounts of olive cake are generated after olive oil extraction, representing an environmental pollutant whose disposal is highly expensive for olive-processing companies. Using olive cake in ruminant feeding is a possible alternative, as it is a good source of fiber and contains polyphenols, although its nutritive value needs to be properly assessed. In this study, we evaluated the effects of replacing 33% of the forage (maize silage and barley straw) by olive cake (16.6% of total diet) in a mixed diet for dairy ruminants on in vitro ruminal fermentation using Rusitec fermenters. Olive cake inclusion increased diet degradability, whereas rumen fermentation, microbial growth, and microbial populations were not modified. Results indicate that maize silage and barley straw could be partially replaced by olive cake in a diet for dairy sheep without compromising rumen fermentation. The use of olive cake in ruminant diets could be especially indicated in periods of forage scarcity.Olive oil extraction generates large amounts of a highly pollutant by-product called olive cake (OC), and its use in ruminant feeding could be an alternative. This study was designed to evaluate the effects of partially replacing forage by crude OC (COC) in a mixed dairy diet on rumen fermentation and microbial populations in Rusitec fermenters. The COC replaced 33% of the forage (66% maize silage and 33% barley straw) and was included at 16.6% of the total diet. Four fermenters were used in a cross-over design with two 13-day incubation periods. Experimental diets had a 50:50 forage-to-concentrate ratio and were formulated to contain the same protein (16.0%) and neutral detergent fiber (32.5%) levels. Compared with control fermenters, those fed the COC diet showed greater (p ≤ 0.02) pH (6.07 vs. 6.22), diet disappearance (0.709 vs. 0.748), and butyrate proportions (18.0 vs. 19.4), but there were no differences in volatile fatty acids and ammonia production. Microbial growth, bacterial diversity, protozoal abundance, and relative abundance of fungi and archaea were unaffected by diet, although the solid phase of COC-fed fermenters showed greater (p = 0.01) bacterial abundance than control ones. Results indicate that COC could replace 33% of the forage in a mixed dairy diet.

Evaluation of Feed Value of Barley Fodder as an Alternative Feed Ingredient

Barley is an important cereal gain which is traditionally used in some nations of Asia and North Africa, and there has been growing interest in using barley as an ingredient in food due to their nutritional value and high content of phyto-constituents. However, no study report on comparative feed value between sprouted barley, cornflake and alfalfa hay. Therefore, in this study we aimed to evaluate the chemical composition, amino acid profile and mineral content of 6 day sprouted barley fodder (SBF) compared with cornflake and alfalfa hay using by AOAC method, as an alternative feed ingredient. Results showed that SBF had higher content of crude protein, acid detergent insoluble crude proteins and neutral detergent insoluble crude protein than alfalfa hay and cornflake; cornflake had higher crude fiber, neutral detergent fiber content than SBF and alfalfa hay; alfalfa hay had higher crude fiber, crude ash, acid detergent fiber, neutral detergent fiber and lignin level than SBF and cornflake. Also, significant differences were found on amino acid content among them (p<0.01). The most abundant amino acid in SBF was glutamate (123 g/kg DM), which is higher than in alfalfa hay (1.27%) or cornflake (1.58%). However, methionine (1.33%) and cysteine (1.53%) were the least abundant amino acids in SBF compared with cornflake or alfalfa hay. Furthermore, our study results exhibited that SBE comprise a good sources of minerals including ferrous (90.01 mg/kg) followed by zinc (20.50 mg/kg), magnesium (0.20 mg/kg) and sodium (0.03 mg/kg) as compared to cornflake and alfalfa hay. The present research findings, confirmed that the nutritional values of SBF are comparable to those of cornflake and alfalfa hay. Hence, SBF can be a better alternative feed ingredient for cornflake or alfalfa hay. However, feeding trials will be required to determine acceptability of SBF for ruminant production.

Effect of arbuscular mycorrhizal inoculation on the quality and in vitro gas production of einkorn wheat straw

The purpose of this study was to determine the effects of arbuscular mycorrhizal (AM) inoculation on the quality of einkorn wheat straw (EWS) and in vitro gas production (GP). It was found that AM inoculation of EW seed before sowing caused significant increases in crude protein (CP), ether extract (EE), neutral detergent fibre (NDF), zinc (Zn), copper (Cu), and iron (Fe) levels of straw, and a (P &lt;0.05) decrease in crude ash (CA), metabolizable energy (ME), and organic matter digestibility (OMD) compared with the straw of non-inoculated EW. The observed difference in the average GP among the between EWS from plants grown from inoculated seed and those from the untreated control was significant at all times between the third and 96th hour. However, when the GP kinetics of the groups was examined after 96 hours’ incubation, only the difference in the gas amount of the easily soluble fractions of feeds was significant. The GP from the slowly fermented part, the GP rate constant and the potential GP of the straws were not affected by the AM inoculation (P &gt;0.05). Thus, inoculation of einkorn wheat with AM altered the nutritional value of the straw produced creating a roughage with decreased value for feeding ruminant livestock.&#x0D; Keywords: artificial rumen, fermentation kinetics, nutrient digestibility

Yield of milk and milk constituents of lactating dairy cows fed on paddy straw plus non-forage fibre sources based complete rations having varying levels of neutral detergent fibre

A study of six months duration was conducted to assess the yield of milk and milk constituents of lactating dairy cows fed on paddy straw plus non-forage fibre sources based complete rations containing different levels of NDF, in two phases, viz., early and mid lactation. Three isonitrogenous and isocaloric complete rations, T 1 , T 2 and T 3 with 25, 30 and 35 per cent NDF, respectively were formulated as per the recommendations of ICAR-NIANP (2013). Paddy straw was the sole source of roughage NDF, in all the three rations. Eighteen dairy cows yielding approximately 10 kg of milk per day were divided into three groups of six each and allotted to the three experimental rations. The average daily milk yield of cows fed on the experimental rations, T 1 , T 2 and T 3 , in phases I and II were similar (P 0.05). All these yields were highest in cows of T 3 , followed by T 2 and T 1 , in descending order, with the values in the three dietary treatments being significantly different (P<0.05), among themselves in phase II as well as the total experiment. A thorough evaluation of the results obtained in the present study, reveal that the animals in all the three dietary treatments performed well, with the complete rations T 3 with 35 per cent NDF and T 2 with 30 per cent NDF, showing better performance than T 1 with 25 per cent NDF. Among T 2 and T 3 which were more or less comparable in milk yield, the cows fed on diet T 3 remained in peak milk yield for longer period than those in T 2 . The cows fed on diet T 3 had a significantly higher (P<0.05) FCM, fat and protein yield in early, mid and total lactation than those fed on the diet T 2 , indicating that T 3 was better than T 2 . These results suggest that complete rations with 25 to 35 per cent NDF, containing paddy straw as the sole source of roughage NDF, can be recommended for use among early and mid lactation dairy cows, with 35 per cent being the ideal NDF level.

Harvest period and baking industry residue inclusion on production efficiency and chemical composition of tropical grass silage

The seasonality of forage production is a challenge for livestock production in Brazil. Elephant grass (Pennisetum purpureum Schum.) silage is a widely cultivated forage however, this plant may represent high moisture levels and other unfavorable traits for ensiling and conservation during the ideal harvest period. The purpose of this experiment was to evaluate the effect of harvest period and the inclusion of bakery residue on silage traits and chemical composition. Elephant grass was harvested and ensiled into mini-silos 70, 84, and 98 days after regrowth, with the addition of 0, 5, 10, or 15% of bakery residue. After 45 days, the mini-silos were opened to evaluate the chemical composition and traits of the silage. The design was completely randomized in a full factorial arrangement with three harvest periods and four doses of bakery residue (3 × 4), with four replicates (mini-silos) per treatment (n = 48). The tests for all the assumptions of variance analyses were conducted. The effects of harvest period (days) and concentration of residue (%) were evaluated using orthogonal polynomial contrasts, adopting the polynomial with a greater degree of significance (p < 0.05). Harvest period did not influence the dry matter content of elephant grass silage (p = 0.2126). Similarly, the inclusion of bakery residue in elephant grass silages did not affect the pH (p = 0.1466); however, it linearly increased the temperature (p < 0.0001), NH3/N total (p < 0.0001), non-fibrous carbohydrates (p = 0.0024), and dry matter recovery (p < 0.0001). The increases in bakery residue linearly reduced (p = 0.0497) effluent production of elephant grass harvested at 70 days. The inclusion of bakery residue in elephant grass silages decreased the neutral (p < 0.0001) and acid detergent fiber (p < 0.0001) levels. The inclusion of bakery residue decreases effluent production, increases dry matter recovery, and improves the chemical composition of elephant grass silage.

Enteric methane, lactation performances, digestibility, and metabolism of nitrogen and energy of Holsteins and Jerseys fed 2 levels of forage fiber from alfalfa silage or corn silage

Our objective was to determine the effects of replacing alfalfa silage (AS) neutral detergent fiber (NDF) with corn silage (CS) NDF at 2 levels of forage NDF (FNDF) on enteric methane (CH4), lactation performance, ruminal fluid characteristics, digestibility, and metabolism of N and energy in Holstein and Jersey cows. Twelve Holstein and 12 Jersey cows (all primiparous and mid-lactation) were used in a triplicated split-plot 4 × 4 Latin square experiment, where breed and diet formed the main and subplots, respectively. The 4 iso-nitrogenous and iso-starch dietary treatments were arranged as a 2 × 2 factorial with 2 levels of FNDF [19 (low FNDF, LF) and 24% (high FNDF, HF) of dry matter] and 2 sources of FNDF (70:30 and 30:70 ratio of AS NDF to CS NDF). Soyhull (non-forage NDF) and corn grain were respectively used to keep dietary NDF and starch content similar across diets. Total collection of feces and urine over 3 d was performed on 8 cows (1 Latin square from each breed). The difference in dry matter intake (DMI) between Holsteins and Jerseys was greater when fed AS than CS. Compared with Jerseys, Holstein cows had greater body weight (48%), DMI (34%), fat- and protein-corrected milk (FPCM; 31%) and CH4 production (22%; 471 vs. 385 g/d). However, breed did not affect CH4 intensity (g/kg of FPCM) or yield (g/kg of DMI), nutrient digestibility, and N partitioning. Compared with HF, LF-fed cows had greater DMI (10%), N intake (8%), and FPCM (5%), but they were 5% less efficient (both FPCM/DMI and milk N/intake N). Compared with HF, LF-fed cows excreted 11 and 17% less urinary N (g/d and % of N intake, respectively). In spite of lower (2.5%) acetate and higher (10%) propionate (mol/100 mol ruminal volatile fatty acids) LF-fed cows had greater (6%) CH4 production (g/d) than did HF-fed cows, most likely due to increased DMI, as affected mainly by the soyhulls. Compared with AS, CS-fed cows had greater DMI (7%) and FPCM (4%), but they were less efficient (5%), and CH4 yield (g/kg of DMI) was reduced by 8%. In addition, per unit of gross energy intake, CS-fed cows lost less urinary energy (15%) and CH energy (11%) than did AS-fed cows. We concluded that, in contrast to level and source of FNDF, breed did not affect digestive and metabolic efficiencies, and, furthermore, neither breed nor dietary treatments affected CH4 intensity. The tradeoff between CH4 and N losses may have implications in future studies assessing the environmental effects of milk production when approached from a whole-farm perspective.

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Performance of sheep grazing &lt;i&gt;Panicum maximum&lt;/i&gt; cv. Massai and supplemented with protein sources during the dry season

The low quality of tropical grasses in the dry season justifies the use of dietary supplements to meet the nutritional needs of sheep. The objective of this study was to evaluate the effect of supplementation with high-protein feed on mutton sheep performance and yield in Massai grass pastures during the dry season. The treatments corresponded to four supplements, namely Leucaena leucocephala leaf hay, Gliricidia sepium leaf hay, soybean meal, and a treatment that received only multiple mixture (protein salt) ad libitum. The pasture was evaluated for canopy height, forage supply, and chemical composition of leaf blade, stem and dead material. Average daily gain, weight gain per area, and the stocking rate were also evaluated. There were four grazing cycles because the grazing method was rotational stocking with seven days of occupation and 35 days of rest. The interaction between supplements and grazing cycles was not significant, and no effects of the supplements were found for any of the variables. The highest forage and leaf blade offerings were observed in the first grazing cycle. The highest levels of crude protein and lower neutral detergent fibre and lignin of pasture components were observed in cycles 3 and 4. The highest average daily gains per animal and per area were observed in cycles 1 and 2. Protein supplementation of sheep in Massai grass pastures promotes satisfactory gains during the dry season, and Leucaena and Gliricidia hays can be used as protein sources instead of soybean meal.&#x0D; Keywords: Gliricidia sepium, leguminous, Leucaena leucocephala, pasture

Comparison of milk production, intake, and total-tract nutrient digestion in lactating dairy cattle fed diets containing either wheat middlings and urea, commercial fermentation by-product, or rumen-protected soybean meal

The objective of this study was to evaluate the effects of a commercially available fermentation by-product in a diet containing adequate rumen-degradable protein (RDP) on milk performance, intake, and total-tract nutrient digestion in lactating dairy cattle. Primiparous (n = 48) and multiparous (n = 144) lactating dairy cattle were stratified by milk production and randomly allocated into 12 pens containing 4 primiparous and 12 multiparous animals each. Cattle averaged 118 d in milk and 712 kg of body weight at trial start. Treatment diets, on a dry matter (DM) basis, consisted of 42% corn silage, 13% alfalfa hay and silage, 20% grain corn, and 25% protein premix containing either soybean meal, wheat middlings, and urea (SBM+U), soybean meal and fermentation by-product (SBM+F), or soybean meal and rumen-protected soybean meal (RP-SBM). All 3 diets provided a similar level (DM basis) of neutral detergent fiber analyzed using α-amylase and sodium sulfite and corrected for ash content (31%), crude protein (CP, 14.9%), starch (26%), and metabolizable energy (2.7 Mcal/kg), and differed in sources of RDP. The trial consisted of a 2-wk adaptation and covariate period during which all cows were fed the RP-SBM diet and covariate measurements were taken. Pens were then randomly allocated to treatments, and weekly measurements of milk production, intake, body weight, and condition score were taken for 10 wk. All data were analyzed using the Proc Mixed procedure in SAS (SAS Institute Inc., Cary, NC). Increased DM intake was observed for cows fed SBM+F compared with cows fed SBM+U and RP-SBM (28.3 vs. 26.9 and 26.7 kg/d, respectively). Cows fed SBM+F produced more energy-corrected milk (45.3 kg/d) compared with cows fed SBM+U and RP-SBM (43.6 and 43.7 kg/d, respectively). Milk protein yield was also increased in cows fed SBM+F. No differences were observed with body weight or condition score gain throughout the trial. Apparent total-tract digestibility of fiber was decreased in cows fed SBM+F, likely as a result of increased intake. Responses are consistent with previous research in our laboratory that demonstrated a decrease in ruminal CP degradation, leading to an increase in metabolizable protein supply in the small intestine. The fermentation by-product might be useful in diets containing adequate amounts of RDP from soybean meal or alfalfa. The results from this experiment demonstrate beneficial milk performance responses to fermentation by-product when fed with a source of RDP.

Influences of starter NDF level on growth performance and rumen development in lambs fed isocaloric and isonitrogenous diets.

Neutral detergent fiber (NDF), as the main component of structural carbohydrate in forage, is a vital factor impacting the performance of young ruminants. The objective of this study was to evaluate the effect of starter NDF level on the rumen fermentation and morphometrics of lambs fed isocaloric and isonitrogenous diets. One hundred Hu sheep lambs (18 days of age and 6.1 ± 0.1 kg body weight [BW]) were randomly assigned to one of the four starter diets differing in their NDF levels on a dry matter (DM) basis: 1) diet with 14% NDF (NDF14), 2) diet with 18% NDF (NDF18), 3) diet with 22% NDF (NDF22), and 4) diet with 26% NDF (NDF26). Lambs were fed milk replacer with designed starters from 21 to 60 d of age and then transitioned to the same starter feed until 90 d of age. Six lambs from each treatment (close to the average BW of the corresponding treatment) were selected and slaughtered at 90 d of age for measuring rumen fermentation, anatomical development, and morphometric characteristics. Lambs receiving NDF22 and NDF26 starter diets had greater (P < 0.05) intake of starter and total DM, and average daily gain during the overall period, thereby heavier (P < 0.05) final weights at 90 d of age compared with those fed NDF14 starter diet. At 90 d of age, lambs fed NDF22 and NDF26 starters had higher rumen pH, followed by lower propionate, higher acetate concentrations (P < 0.05), and a higher acetate-to-propionate ratio compared with those fed NDF14 and NDF18 starters (P < 0.05). No significant differences of the full and empty weight of reticulorumen were observed among treatments; however, the reticulorumen weight expressed as a percentage of the complex stomach weight was lower (P < 0.05) in lambs fed NDF22 and NDF26 starters compared with those fed NDF14 starter. Furthermore, NDF14 lambs had the thickest keratin layer and epithelium compared with those in the other treatments but showed the thinnest muscle layer (P < 0.05). These results suggest that increasing starter NDF levels can ameliorate the rumen fermentation environment and alleviate hyperkeratosis and plaque formation in the rumen epithelium. In summary, including 22% and 26% NDF in the pelleted starter can improve the performance of lambs.