Source Of Neutral Detergent Fiber Research Articles

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.

Partial corn replacement by soybean hull, or hay supplementation: Effects of increased NDF in diet on performance, metabolism and behavior of pre-weaned calves

The solid diet is a determining factor for ruminal development in calves. However, it is still unclear what is the optimal content and the best way to include fiber in the diet of pre-weaned calves. Thirty-five Holstein calves were used in a randomized block design, considering the sex, weight and birth date of the calves as blocking factor. Animals were housed in individual suspended cages without bedding and assigned to one of three treatments: (1) 22NDF: conventional ground starter concentrate with 220 g neutral detergent fiber (NDF)/kg dry matter (DM); (2) 31NDF: ground starter with 310 g NDF/kg DM, with partial replacement of corn by soybean hull; and (3) 22NDFhay: conventional starter with 220 g NDF/kg DM plus coast-cross hay fed separately ad libitum. The calves received 4 L of milk replacer with 12.5% solids, divided into two meals daily. Feed intake was measured daily. Weight gain and metabolic indicators of intermediate metabolism were evaluated weekly. Ruminal fluid was collected on week 4, 6 and 8 of age. The experiment lasted for 56 days. The increase of the NDF content in the concentrate starter up to 310 g/kg DM with replacement of corn by soybean hull or hay supplementation did not change the starter intake and performance of calves at weaning. The 31NDF diet resulted in higher concentration of short chain fatty acid (SCFA) at week 4, but 22NDF diet increased total SCFA concentration at week 8. Hay supplementation increased rumination time, and decreased non-nutritive oral behaviors during last week preweaning. Dietary NDF levels used in the ground starter concentrate may be higher than current recommendations without reducing intake and performance, as long as the NDF source has low ADF and lignin.

Neutral detergent fiber increases endogenous ileal losses but has no effect on ileal digestibility of amino acids in growing pigs

Two experiments were conducted to determine the effect of neutral detergent fiber (NDF) on endogenous amino acids and protein ileal losses; and also apparent ileal digestibility (AID), and standardized ileal digestibility (SID) of amino acids and crude protein. Sixteen barrows were fed four protein-free diets containing graded NDF levels in Experiment 1. NDF was a mixture of sugarcane bagasse and corn leaves (SBCL). Twenty-four barrows were fed diets with soybean protein concentrate (SPC) or casein as protein sources and SBCL or corncobs (CC) as NDF sources in Experiment 2. In Experiment 1, a linear increase (P < 0.05) in endogenous amino acid and protein ileal losses was observed with increased NDF levels, except for arginine, histidine, methionine and proline. In Experiment 2, protein (P < 0.001) and NDF (P < 0.01) sources significantly affected AID of dry matter, which was higher in casein diets (71.7%) and CC diets (70.7%). Protein and NDF sources significantly affected (P < 0.05) SID of crude protein, which was higher in casein diets (92.8%) and CC diets (92.7%). NDF source had no effect (P > 0.05) on SID of amino acids. Overall, this study showed that NDF increased endogenous amino acid and protein ileal losses, but did not affect ileal digestibility of amino acids.

Effects of corn-based diet starch content and neutral detergent fiber source on lactation performance, digestibility, and bacterial protein flow in dairy cows

An experiment was conducted to evaluate the effects of corn-based dietary starch content and source of neutral detergent fiber (NDF) on lactation performance, nutrient digestion, bacterial protein flow, and ruminal parameters in lactating dairy cows. Eight ruminally cannulated multiparous Holstein cows averaging 193±11d in milk were randomly assigned to treatments in a replicated 4×4 Latin square design with 21-d periods. Treatment diets were high corn grain (HCG; 38% corn silage, 19% dry ground corn, and 4% soy hulls), high soy hulls (HSH; 38% corn silage, 11% dry ground corn, and 13% soy hulls), high corn silage (HCS; 50% corn silage, 6% dry ground corn, and 4% soy hulls), and low corn silage (LCS; 29% corn silage, 15% corn, and 19% soy hulls). The HCG, HSH, HCS, and LCS diets contained 29, 23, 24, and 22% starch; 27, 32, 30, and 32% total NDF; and 21, 21, 25, and 17% forage NDF (dry matter basis), respectively. Mean dry matter intake and milk yield were unaffected by treatment. Cows fed LCS had reduced milk fat content compared with HSH and HCS. The concentration of milk urea nitrogen was greater for cows fed HCS compared with the other treatments. Total-tract digestion of NDF was reduced for cows fed the HCG diet. Total-tract starch digestion was increased for cows fed the HSH and HCS compared with HCG and LCS diets. Bacterial protein flow was unaffected by treatment. Ruminal ammonia concentration was reduced in cows fed the HCG and LCS diets compared with the HCS diet. Ruminal propionate increased and the acetate:propionate ratio decreased in cows fed the LCS diet compared with the HCS diet. Ruminal pH was greater for cows fed the HCS diet compared with cows fed the LCS diet. Diet digestibility and performance of mid- to late-lactation cows fed reduced-starch diets by partially replacing corn grain with soy hulls or corn silage was similar to or improved compared with cows fed a normal-starch diet.

Comportamento ingestivo de cordeiros e digestibilidade dos nutrientes de dietas contendo alta proporção de concentrado e diferentes fontes de fibra em detergente neutro

Dois experimentos foram realizados para avaliar os efeitos da substituição da fibra em detergente neutro (FDN) do bagaço de cana-de-açúcar in natura pela FDN da casca de soja em dietas com alta proporção de concentrado sobre o comportamento ingestivo de cordeiros e a digestibilidade dos nutrientes. No primeiro experimento, 60 cordeiros com 16,4 ± 0,3 kg de peso corporal e idade inicial de 67 ± 2 dias foram distribuídos em delineamento de blocos completos casualizados, em esquema fatorial 2 × 2 + 1, composto de duas fontes de FDN (bagaço de cana in natura ou casca de soja), dois teores de FDN (14 ou 18%) e uma dieta controle contendo 100% de concentrado. No segundo experimento, cinco cordeiros foram distribuídos em quadrado latino 5 × 5 e submetidos às mesmas dietas do experimento 1. As dietas contendo as fontes de fibra promoveram maior consumo de matéria seca, matéria orgânica e FDN e maior tempo de ingestão, ruminação e mastigação (minutos/dia) em comparação à dieta contendo 100% de concentrado. As dietas contendo o bagaço de canade-açúcar in natura proporcionaram maior atividade de ruminação que aquelas com casca de soja. Entretanto, a utilização da casca de soja proporcionou menor atividade de mastigação e maior digestibilidade dos nutrientes em relação ao bagaço de cana-de-açúcar in natura. A casca de soja pode ser utilizada como única fonte adicional de FDN em dietas contendo alto teor de concentrado para cordeiros.

Dietary level and source of neutral detergent fiber and ileal endogenous nitrogen flow in pigs

Two experiments were conducted to study the effect of dietary level and source of neutral detergent fiber (NDF) on ileal dry matter flow and on total and endogenous N flow at the terminal ileum. Twenty-two crossbred 6-wk-old castrated male pigs with an average BW of 9 kg were used. The pigs were fitted with a post-valvular T-cecal cannula and two indwelling blood catheters. During the experimental period of 10 d, the pigs were 11 wk of age with an average BW of 14 kg. They were fed 2.6 times their maintenance requirement for energy of a corn starch-based, semisynthetic diet. The diets contained 178 g of soy isolate/kg as the only source of nitrogen (N). In diets of Exp. 1, purified NDF was included at 0 and 200 g/kg of feed at the expense of glucose. The diets of Exp. 2 contained one of the three different NDF sources (purified NDF, wheat bran, or sunflower hulls) at a level of 144 g of NDF/kg of DM. The purified NDF (pNDF) was isolated from the same batch as the wheat bran (WB) used in Exp. 2. The endogenous N flow at the terminal ileum of these pigs was determined with the 15N-isotope dilution method. The inclusion of NDF in the experimental diets increased (P < .05) the daily DM flow at the terminal ileum. Dry matter flow was increased .697 g for every g/kg increase in NDF in the diet. The different sources of dietary NDF gave similar (P > .05) ileal DM flows.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of Source of Neutral Detergent Fiber and Starch on Nutrient Utilization by Dairy Cows

Two diets were formulated to contain 30% NDF (DM basis) but differed in source of NDF and type of concentrate. One diet contained approximately 70% alfalfa silage and 30% corn grain (89% of NDF from forage) and the other diet contained about 50% alfalfa silage and 50% barley grain (65% of NDF from forage). Diets were fed to 12 cows in a short production trial, a total collection digestion experiment, and a rate of passage study. Cows fed the alfalfa-corn diet produced more 4% FCM (22.4 vs. 20.7 kg/d) than did cows fed the alfalfa-barley diet. Intake of DM (3.7% of BW), NE1 (35 Mcal), and NDF (1.1% of BW) were similar between diets, but due to differences in diet composition, intake of ADF was greater by cows fed alfalfa-corn than by cows fed alfalfa-barley. Digestibilities of DM, NDF, and CP were not affected by diet, but hemicellulose digestion was higher and cellulose and ADF digestibilities were lower by cows fed alfalfa-barley diets. Cows fed alfalfa-corn diet had a higher ruminal acetate to propionate molar ratio. No effect of diet was observed on turnover kinetics of the forage, concentrate, or liquid markers. These data show that forage to grain ratio and source of starch must be considered prior to recommending that diets be balanced for NDF.