Neutral Detergent Fiber Intake Research Articles

Bamboo forage in Peruvian Amazon: a potential feed for cattle.

During the dry and rainy seasons of the Northeastern Zone of Peru, a chemical characterization of five species of bamboo prevalent in the area (Guadua lynnclarkiae, G. takahashiae, Bambusa vulgaris, G. weberbaueri, and Dendrocalamus asper) was conducted. Then, the effect of supplementing bamboo leaves (0, 20, and 40% inclusion of D. asper) on the intake and live weight gain of 18 Gyr × Holstein heifers was evaluated for 28 days. Among the species evaluated, D. asper has the greatest crude protein (CP) concentration (158-166 g/kg Dry matter- DM), post-ruminal CP supply (127 g/kg DM), and in vitro organic matter digestibility (444-456 g/kg DM) but similar concentrations of crude ash (124 g/kg DM), calcium (2.4-2.8 mg/g), phosphorus (0.7-2.1 mg/g), protein fractions A, B1, B2, B3, C (45, 5, 35, 56, and 17g/kg DM, respectively), rumen-undegraded CP (31% CP), neutral detergent fiber (NDF, 685g/kg DM), and acid detergent fiber (ADF,357 g/kg DM) than the other species evaluated. Dry matter intake was higher in the control treatment and in the 20% bamboo leaf inclusion treatment than in the 40% bamboo inclusion treatment. Intake of CP and NDF decreased with the increase in bamboo inclusion. Despite the differences in DM, CP, and NDF intake, the live weight gain remained similar across treatments. However, there was a greater feed conversion in the 20% bamboo leaf inclusion treatment. During the dry season, bamboo leaves can be used as an alternative supplement at a maximum inclusion of 20% without affecting the live weight gain.

Licury Cake in Diets for Lactating Goats: Intake, Digestibility, Feeding Behavior, Milk Production and Composition, and Nitrogen Metabolism.

The objective of this study was to determine the effects of licury cake (LC) inclusion in the diets of lactating goats on productive and metabolic performance. Twelve lactating goats, eight Saanen and four Anglo-Nubian, were distributed in a triplicate 4 × 4 Latin square design, with four treatments (0, 66.7, 133.3, and 200 g kg-1 of dry matter-DM). On the one hand, the LC inclusion increased neutral detergent fiber, indigestible neutral detergent fiber, and potentially digestible neutral detergent fiber (p < 0.001) intake. On the other hand, LC inclusion reduced ether extract and non-fibrous carbohydrate (p < 0.001) intake. There was a reduction in dry matter digestibility (p = 0.018) and an increase in neutral detergent fiber digestibility (p = 0.036). Feeding (p = 0.005) and rumination (p < 0.001) efficiencies increased with LC inclusion. The nitrogen balance was similar for all tested diets; however, we observed recycling metabolism. Based on the studied parameters, mainly milk production and composition, we recommend the LC inclusion of up to 200 g kg-1 DM in diets for lactating goats.

Mathematical Models to Predict Dry Matter Intake and Milk Production by Dairy Cows Managed under Tropical Conditions

This study aimed to create an equation to predict dry matter intake (DMI) and milk production and N-ureic in the milk of dairy cows managed in tropical conditions in Brazil. We used 113 observations from three experiments using lactating Jersey, Girolando, and Holstein cows. The goodness of fit of the developed equations was evaluated using the coefficients of determination (r2) and root mean square error (RMSE). There was a positive correlation between body weight and milk yield (MY) of r = 0.73. The equation considered DMI to be the most important variable to estimate the MY (r2 = 0.65). Four equations were adjusted to estimate the DMI, where, by a stepwise procedure, the first variable included in the equation was the neutral detergent fibre intake, which explained 92% of the DMI of the cows. However, when the variables BW, MY, and milk fat were included in the equation, there was a reduction of 0.06 in RMSE and an increase in precision (r2 = 0.94). The nutrient intake, milk production, and characteristics prediction equations present satisfactory precision and accuracy for dairy cows managed in tropical conditions in Brazil.

Effect of NDF levels of complete pelleted diet and dietary transition period on rumen pH, growth performance, digestibility, and blood indices in fattening male goats

This study aimed to evaluate the effects of low and high NDF levels in complete pelleted diets (CPD) on early diet transition in fattening male goats. Forty male goats were blocked by their initial body weights (BW), and within each block, animals were randomly assigned to one of the four diets using a randomized complete block design. The treatments were arranged in a 2 × 2 factorial comprising of two levels of NDF (20.2% and 32%) and two diet transition strategies (day 7 and 15). All the diets were iso-nitrogenous, having a 15:85 forage-to-concentrate ratio. In the high NDF diet, a higher level of 32% was achieved by replacing corn grain with soy hulls and wheat bran. The goats were housed individually and had ad libitum access to feed and water. During the transition phase, conventional feeding was replaced by the CPD in three steps, and thereafter, all animals had free choice access to their respective diets. Body weight and blood samples were conducted weekly, while rumen samples were collected on day 0, 7 and 15, and then fortnightly. Feeding behavior data was recorded on day 7 during the transition period using video cameras. Nutrient digestibility was performed twice, with n = 4 animals/treatment: 1) after 15 days and 2) at the end of the study. The results revealed that goats fed on a high NDF diet had higher (P < 0.05) DMI and ADG than those fed on a low NDF diet during the transition. Additionally, there was an interaction between NDF and transition days after the transition period and the entire study period. The feed-to-gain ratio was lower (P = 0.05) in goats fed on the LNDF-15 compared with the LNDF-7. The rumen pH of low NDF-7 goats was lower (P < 0.05) throughout the study compared with other treatments. Moreover, the odds for diarrhea were higher (P = 0.03) in the low NDF-7 goats compared to other treatments during and after the diet transition. Male goats fed on a high NDF diet had higher (P < 0.05) nutrient digestibility after transition, but no effect thereafter. Animals fed on a high NDF diet had higher (P < 0.05) DMI, NDF intake, laying, standing time, and rumination time during the diet transition period. Feeding behavior was not recorded after the dietary transition period. In conclusion, feeding HNDF-7 to goats during the diet transition period resulted in improved growth performance, key feeding behavior parameters, and nutrient digestibility. Whereas, during the post-diet transition period, both LNDF-15 and HNDF-7 goats displayed comparable growth performance without any adverse effects on animal health.

Effect of nitrate supplementation, dietary protein supply, and genetic yield index on performance, methane emission, and nitrogen efficiency in dairy cows

The objective was to investigate the effect of nonprotein nitrogen source, dietary protein supply, and genetic yield index on methane emission, N metabolism, and ruminal fermentation in dairy cows. Forty-eight Danish Holstein dairy cows (24 primiparous cows and 24 multiparous cows) were used in a 6 × 4 incomplete Latin square design with 4 periods of 21-d duration. Cows were fed ad libitum with the following 6 experimental diets: diets with low, medium, or high rumen degradable protein (RDP):rumen undegradable protein (RUP) ratio (manipulated by changing the proportion of corn meal, corn gluten meal, and corn gluten feed) combined with either urea or nitrate (10 g NO3-/kg of dry matter) as nonprotein nitrogen source. Samples of ruminal fluid and feces were collected from multiparous cows, and total-tract nutrient digestibility was estimated using TiO2 as flow marker. Milk samples were collected from all 48 cows. Gas emission (CH4, CO2, and H2) was measured by 4 GreenFeed units. We observed no significant interaction between dietary RDP:RUP ratio and nitrate supplementation, and between nitrate supplementation and genetic yield index on CH4 emission (production, yield, intensity). As dietary RDP:RUP ratio increased, intake of crude protein, RDP, and neutral detergent fiber and total-tract digestibility of crude protein linearly increased, and RUP intake linearly decreased. Yield of milk, energy-corrected milk, and milk protein and lactose linearly decreased, whereas milk fat and milk urea nitrogen concentrations linearly increased as dietary RDP:RUP ratio increased. The increase in dietary RDP:RUP ratio resulted in a linear increase in the excretion of total purine derivatives and N in urine, but a linear decrease in N efficiency (milk N in % of N intake). Nitrate supplementation reduced dry matter intake (DMI) and increased total-tract organic matter digestibility compared with urea supplementation. Nitrate supplementation resulted in a greater reduction in DMI and daily CH4 production and a greater increase in daily H2 production in multiparous cows compared with primiparous cows. Nitrate supplementation also showed a greater reduction in milk protein and lactose yield in multiparous cows than in primiparous cows. Milk protein and lactose concentrations were lower for cows receiving nitrate diets compared with cows receiving urea diets. Nitrate supplementation reduced urinary purine derivatives excretion from the rumen, whereas N efficiency tended to increase. Nitrate supplementation reduced proportion of acetate and propionate in ruminal volatile fatty acids. In conclusion, no interaction was observed between dietary RDP:RUP ratio and nitrate supplementation, and no interaction between nitrate supplementation and genetic yield index on CH4 emission (production, yield, intensity) was noted. Nitrate supplementation resulted in a greater reduction in DMI and CH4 production, and a greater increase in H2 production in multiparous cows than in primiparous cows. As the dietary RDP:RUP ratio increased, CH4 emission was unaffected and RDP intake increased, but RUP intake and milk yield decreased. Genetic yield index did not affect CH4 production, yield, or intensity.

Between-individual variability on reticulorumen digesta passage rate in goats

Identifying factors that influence an individual’s ability to utilize nutrients is a strategy for enhancing livestock sustainability. Digesta passage rate (kp) is one of the most important determinants that influence nutrient utilization. However, there is limited knowledge regarding the individual’s variability on kp. The objective of this study was to investigate between-individual variability of reticulorumen (RR) kp of solutes and particles in goats, and its relationship to total NDF digestibility (NDFd). A dataset consisting of 103 individual records from two studies of castrated male (n = 36), female (n = 34), and intact male (n = 33) growing Saanen goats fed ad libitum and slaughtered at around 16.62 ± 0.96 (n = 21), 23.09 ± 1.33 (n = 19), 30.67 ± 2.25 kg (n = 29), 38.02 ± 1.61 (n = 16), and 44.12 ± 1.95 (n = 18) kg BW was used. The RR kp of solutes and particles were measured using Cr-EDTA and indigestible NDF (iNDF), respectively. Using mixed-effect models, considering sex and BW as fixed effects and study as random effect, we aimed to identify meaningful between-individual variance of RR kp of solutes and particles. Given the characteristic of our dataset (i.e., one observation per individual), our approach focused on exploring the variance between individuals described by the residuals of our fitted models. The RR kp of solutes and particles showed significant (P < 0.05) between-individual variation (CV ≈ 27%). Only 10% of RR kp of solutes variance was explained by DM intake (DMI) (g/d and g/d and g/kg BW) and NDF intake (NDFI); g/d), while 51.8% of the variance in RR kp of particles was explained by DMI and NDFI (g/d and g/kg BW), RR wet pool size, and iNDF:NDF intake ratio. The between-individual variation of RR kp of particles explained 19.5% of the between-individual variation in NDFd (P < 0.001). However, the nutritional and individual traits cited above (i.e., DMI, NDFI, RR wet pool size, and iNDF:NDF intake ratio) explained only 51.8% of the between-individual variation of RR kp of particles, while the remaining 48.2% was attributed to the individual’s inherent characteristics, which in turn explained only 1.24% of the between-individual variation of NDFd (P = 0.146). The RR kp of particles and solutes showed meaningful between-individuals variance, which was partially related to both individual inherent characteristics and nutritional and animal traits. However, the NDFd was found to be unrelated to the inherent characteristics of RR kp of particles.

Effect of dietary inclusions of different types of Acacia mearnsii on milk performance and nutrient intake of dairy cows

This study investigated the effects of including different types of Acacia mearnsii (tannin extract and forage) on nutrient intake and milk performance in dairy cattle. Holstein-Friesian x Jersey dairy cows (n per Experiment = 24) that had 200 days in milk were selected for this study in a completely randomized study design. This study was conducted under on-farm conditions at Springfontein dairy farm, a farm that lacked a functional bodyweight scale to measure the cow bodyweight and a computer system to register cow parity. Cows were assigned Acacia mearnsii tannin extract (ATE) pellets which were added with 0 (0ATE), 0.75 (0.75ATE), 1.5 (1.5ATE) or 3 (3ATE) % ATE in pellets while 0ATE was a commercial protein concentrate (Experiment 1). Cows were assigned Acacia mearnsii forage (AMF) at a rate of 0 (0AMF), 5 (5AMF), 15 (15AMF) or 25 (25AMF) % AMF inclusion in corn silage-based diet (Experiment 2). For both Experiments, treatments had six cows each, in which they were adapted (14 d) to diets before data collection (21 d). All AMF inclusions decreased (P<0.0001) dry matter intake (DMI), crude protein intake (CPI), neutral detergent fibre intake (NDFI), acid detergent fibre intake (ADFI) and organic matter intake (OMI) at 25AMF. Linear (P<0.0001) and quadratic (P<0.001) effects were observed on DMI, CPI, NDFI, ADFI and OMI. Inclusions of AMF in corn silage diets affected milk yield, protein yield, lactose yield and milk protein percentage (P<0.001). Linear effect was present in milk yield per DMI (P<0.0001). In conclusion, the dairy cow diet supplemented with ATE pellets did not have a beneficial effect on the nutrient intakes and milk yield. However, the AMF supplemented in corn silage of the dairy cow diet, increased milk production due to positive effects on nutrient intake, which was favourably influenced from a nutritional point of view.

Comparison of sheep and goat preferences for different forms of stoned olive cake.

The objectives of this experiment were to investigate voluntary intake of stoned olive cake (SOC) in sheep and goats. The feeding experiment was carried out with a total of 10 animals consisting of five Karya yearlings and five Saanen goats (28.0 ± 2.0 and 37.0 ± 2.1kg initial body weight (BW), respectively). Three feeds were offered as free-choice: alfalfa hay-maize silage mix (40:60 in dry matter basis), pelleted SOC, and ensiled SOC. Goats had higher (P < 0.001) dry matter (DM) and neutral detergent fiber (NDF) intakes than sheep, although digestible DM and NDF intakes were similar. Goats consumed more (P < 0.05) pelleted SOC and ensiled SOC than sheep as a percentage of total intake (29.2 and 22.4%, respectively). Both sheep and goats preferred (P < 0.001) the silage form of SOC compared to the pelleted form of SOC.

Growth performance, blood metabolites, ruminal fermentation, and bacterial community in preweaning dairy calves fed corn silage-included starter and total mixed ration

The objective of this study was to evaluate the effects of the inclusion of whole-plant corn silage (WPCS) in a starter or total mixed ration (TMR) on growth, blood metabolites, ruminal fermentation, and microbial community in preweaning dairy calves. A total of 45 healthy dairy calves were blocked by date of birth and randomly assigned to 1 of 3 treatments: 100% calf starter (CONS), a mix of 85% calf starter and 15% WPCS [dry matter (DM) basis; CSCS], or 100% WPCS-based lactation TMR (CTMR). Pasteurized normal milk was fed to all the animals under the same regimen. The experiment ran from when the calves were 2 d old to weaning at 63 d. Milk and feed intakes were recorded daily. Growth performance data and blood samples were collected on wk 3, 5, 7, and 9 of the experiment. Rumen fluid was sampled at 40 and 60 d. The 3 treatments had different particle size fractions. The CSCS group had greater medium fraction (<19 mm, >8 mm) and particles retained on 8-mm sieves than the other 2 groups, whereas the CTMR group had the greatest long (>19 mm) and fine (<4 mm) fractions and physically effective neutral detergent fiber (NDF) on 8- and 4-mm sieves, but had the smallest short fraction (<8 mm, >4 mm) and particles retained on 4-mm sieves. The 24-h in vitro digestibility of DM, crude protein (CP), NDF, and acid detergent fiber (ADF) were decreased in order by the CONS, CSCS, and CTMR groups. Compared with the CONS group, the digestibility of ether extract (EE) was lower in the CSCS and CTMR groups, whereas the digestibility of starch was similar among treatments. During the experimental period, the DM, CP, and metabolizable energy intakes from milk, solid feed, and total feed were not affected by treatments. The NDF, ADF, and EE intakes and potentially digestible intakes were greater in the CTMR group than in the other 2 groups. With the exception that body barrel was greater for calves fed CSCS, growth parameters and blood metabolites were similar among treatments. Compared with the CSCS group, the CTMR group had greater rumen pH and total volatile fatty acids, propionate, and isovalerate concentrations, but a lower acetate:propionate ratio. The CTMR group had greater relative abundances of some cellulolytic bacteria (Rikenellaceae RC9 gut group, Christensenellaceae R7, Ruminococcaceae NK4A214, Ruminococcaceae UCG, Ruminococcus, and Erysipelotrichaceae UCG) in the rumen, which may be beneficial for the early acquisition of specific adult-associated microorganisms. In summary, a WPCS-based lactation TMR, but not the WPCS-included starter, had the potential to be an alternative starter in preweaning calves without having significant adverse effects. These findings provide theoretical and practical implications for the rational application of TMR in the early life of dairy calves.

Inclusion of calcium oxide in sugarcane silage under different particle sizes on performance of dairy cows.

Our objective was to evaluate voluntary intake, apparent digestibility, performance, and nitrogen balance of dairy cows fed sugarcane silage under different particle sizes treated or not with calcium oxide (CaO). Eight F1 Holstein/Zebu cows, with body weight of 521.5 ± 55.17kg, and 60 ± 10days in milk were used, distributed into two simultaneous 4 × 4 Latin squares. The treatments were composed of sugarcane into two particle sizes (15 and 30mm) with and without the addition of CaO (10g/kg of natural matter), being the treatments compared according to a 2 × 2 factorial arrangement. Data were analyzed by the MIXED procedure of SAS. The intake of dry matter (13.05kg/day), crude protein, non-fibrous carbohydrates, and neutral detergent fiber was not modified (P > 0.05) by the inclusion of the calcium oxide, nor by particles size and interaction among both. However, there was interaction between CaO and particle size on dry matter digestibility (P = 0.002), being that the CaO was effective in promoting greater DM digestibility in silages with larger particle size. The milk yield and composition were also not affected by the diets (P > 0.05), similarly for nitrogen balance (P > 0.05). The addition of CaO to sugarcane silage with different particle sizes (15 and 30mm) does not affect the milk yield and composition of dairy cows, nor the nitrogen balance. However, when CaO is added to the sugarcane silage under larger particle sizes, there are benefits in DM digestibility.

Effect of partial replacement of Dichanthium spp. hay with Guazuma ulmifolia foliage on hair lambs’ intake, digestibility, and blood metabolites

Extensive livestock management is a common practice in the dry tropics. However, summer conditions can cause high fiber and low protein concentrations, even in grasses adapted to tropical soils, such as Angleton (Dichanthium spp.), widely used in producing small ruminants. On the other hand, Guacimo (Guazuma ulmifolia) is a tree that overcomes high temperatures and hydric stress. This research evaluated the effect of replacing Angleton with four foliage levels of Guacimo on hair lambs’ intake, digestibility, and blood metabolites. Twelve male hair lambs with an average of 22.0 ± 1.3 kg of body weight were used in an experimental 4 × 4 square design. Treatments were as follows: 100 % Angleton hay; 85 % Angleton hay + 15 % Guacimo foliage; 70 % Angleton hay + 30 % Guacimo foliage, and 55 % Angleton hay + 45 % Guacimo foliage. Dry matter (DM), organic matter (OM), crude protein (CP), and neutral detergent fiber (NDF) intake, as well as CP digestibility and glucose concentrations, increased linearly as the level of Guacimo rose (P &gt; 0.05). Guacimo foliage improves intake, blood metabolites, and in vivo digestibility of DM and can be used to replace part of the hay in lamb rations.

Methane emission, intake, digestibility, performance and blood metabolites in sheep supplemented with cupuassu and tucuma cake in the eastern Amazon.

The use of co-products as a feed supplement for ruminants makes livestock sustainable and optimizes the use of available areas and animal performance. Furthermore, when cakes are used, the residual fat composition can influence ruminal metabolism and methane (CH4) production. This study aimed to assess the effects of a diet containing cupuassu (CUP; Theobroma grandiflorum) and tucuma (TUC; Astrocaryum vulgare Mart.) cakes on intake, digestibility, serum metabolites, performance, and CH4 emissions in confined sheep in the Amazon. Approximately 28 animals, Dorper-Santa Inês, castrated, with an average initial live weight (ILW) of 35 ± 2.3 kg, were distributed in metabolic cages, in a completely randomized design, with four treatments and seven replications: (1) Control (C40), without the addition of Amazonian cake and with 40 g of ether extract (EE)/kg of dietary dry matter (DM); (2) CUP, the inclusion of the CUP cake and 70 g of EE/kg; (3) TUC, the inclusion of the TUC cake and 70 g of EE/kg; and (4) Control (C80), without the addition of Amazonian cake and with 80 g of EE/kg of dietary DM, with roughage to concentrate ratio of 40:60. The use of the TUC cake as a feed supplement reduced the intake of DM, crude protein (CP), and EE compared to the inclusion of the CUP cake (p < 0.05); however, it increased the intake of neutral detergent fiber (NDF) by 32% (p < 0.01). The highest averages of DM (732 g/kg) and CP (743 g/kg) digestibility were presented in C40, while the highest digestibility of NDF was presented in TUC (590 g/kg). Albumin levels stayed above and protein levels were below the reference values, and the C40 diet also obtained below results for cholesterol, triglycerides and High Density Lipoprotein (HDL) (P < 0.05). Sheep fed CUP (91 g) and TUC (45 g) had lower daily weight gains (DWGs) than those fed with diets without the inclusion of cakes (C40 = 119 g; C80 = 148 g), and feed efficiency (FE) was also lower in CUP (84) and TUC (60) diets than in C40 (119) and C80 (137) diets. CH4 emissions were lower in animals fed TUC (26 L/day) and higher in C40 (35 L/day); however, TUC resulted in higher CH4 emissions in grams/body live weight (BW) gain/day (353 g/BW/day) vs. 183 g/BW/day (C40), 157 g/BW/day (C80), and 221 g/BW/day (CUP). The supplementation with cakes did not improve intake, digestibility and performance, did not compromise blood metabolites and did not reduce the enteric CH4 emission in confined sheep in the Amazon; however, the use of CUP cake showed similar results to the control treatments and did not increase CH4 emissions, as occurred with the inclusion of TUC cake.

Replacing ground Rhodes grass hay with soyhulls in the pelleted diet: effects on ingestive behavior, nutrient digestibility, blood metabolites, growth performance, and economic viability of intensive fattening Lohi lambs.

This study aimed to evaluate the effects of replacing soyhulls (SH) for ground Rhodes grass hay (RGH) in a pelleted diet on ingestive behavior, digestibility, blood metabolites, growth performance, and economic viability of fattening Lohi lambs. A total of thirty male lambs (age: 5months; body weight 20.4 ± 0.24kg) were allotted to one of the three diets (n = 10 lambs/diet) under a completely randomized design. The diets were with 25% RGH inclusion (control), replacing 15% RGH with 15% SH as a fiber source (SH-15), and containing only 25% SH inclusion on a dry basis (SH-25). Ingestive behavior parameters like time spent (min/day), bouts frequency (number/day), and bout length (min/bout) for feeding, drinking, rumination, chewing, standing, and lying were not influenced (P > 0.05) by replacing RGH with SH. The dry matter (DM) and neutral detergent fiber (NDF) chewing rate, rumination rate, and feeding efficiency were also not changed (P > 0.05) by dietary treatments, whereas total dry matter and NDF intakes, and their rumination efficiencies were lower (P < 0.05) for the SH-25 than for the rest of the treatments. The digestibility of NDF and acid detergent fiber (ADF) was higher (P < 0.05) for the SH-25 than for the rest of the treatments. The concentrations of blood metabolites like glucose, blood nitrogen, and cholesterol were not changed (P > 0.05) among the treatment groups. Similarly, performance parameters like dry matter intake, initial and final body weight, average daily gain, and feed conversion ratio were similar (P > 0.05) across the treatments. However, the incidence of loose fecal consistency was higher (P < 0.05) for SH-25 than for the control. The values of economic efficiency were better for SH-25-fed lambs than those fed the rest of the treatments. Based on the results, substituting SH for RGH in a pelleted diet improved the digestibility of fiber fractions, and economics without affecting the growth performance, and blood metabolites of fattening lambs. However, lower rumination efficiency and loos fecal consistency are evidencing less effectiveness of SH fiber.

Effects of non-protein nitrogen on buffel grass fiber and ruminal bacterial composition in sheep

This study aimed to evaluate different concentrations of non-protein nitrogen (NPN) ruminal infusion in sheep fed buffel grass hay on nutrient intake and digestibility, ruminal parameters, nitrogen balance, and rumen bacterial composition. Five rumen-fistulated adult wethers, weighing 58 ± 5.1 kg were distributed according to a 5 × 5 Latin square design. The control treatment consisted of a 5.5% crude protein (CP) buffel grass hay basal diet only, while the other four treatments consisted of the addition, via ruminal infusion, of increasing amounts of NPN to gradually raise the level of CP in the basal diet (7.44, 9.39, 11.33 and 13.27% CP). There was a quadratic effect for the intake of dry matter (DM), organic matter (OM), CP, ether extract (EE) and neutral detergent fiber (NDF). Values of pH, volatile fatty acids, microbial protein, microbial efficiency and digestibility coefficients were not affected by CP levels in basal diet. On the other hand, there was a linear effect for the concentrations of ammonia nitrogen (NNH3) and nitrogen (N) in urine, and a quadratic effect for ingested and excreted N in feces, as well as for N balance. There was no effect of the different CP levels on the ruminal microbial composition. While the 5.5% CP basal diet provided sufficient NPN supply for the maintenance of ruminal bacterial activity, increased CP concentrations from 7.34 to 8.66% by means of ruminal infusion with NPM optimized the utilization of buffel grass nutrients by sheep.

Effect of kraft pulp inclusion in calf starter on performance, health, and plasma concentration of glucagon-like peptide 2 in calves

Kraft pulp (KP), an intermediate product obtained when wood chips are converted to paper, contains highly digestible fiber. This study evaluated the effect of KP inclusion in calf starters on growth performance, health, and plasma glucagon-like peptide 2 (GLP-2) concentration in calves. Twenty-five Holstein heifer calves were raised on a high plane of nutrition program using milk replacer containing 29% crude protein and 18% fat until 49 d after birth, and were fed calf starters containing KP at 0 (CON; n = 14) or 12% (KPS; n = 11) on a dry matter basis. All calves were fed the treatment calf starters and timothy hay ad libitum. Blood was collected at 4, 14, 21, 35, 49, 70, and 91 d after birth. Dry matter intake (DMI) of milk replacer and hay was not affected by treatment, whereas calf starter DMI was lower for KPS (0.93 kg/d) than for CON (1.03 kg/d). Higher neutral detergent fiber (NDF) content in KPS (31.7%) than in the CON starter (22.1%) resulted in higher NDF intake for KPS (0.55 kg/d) than for CON (0.47 kg/d). However, the consumption of starch was lower for KPS (0.29 kg/d) than for CON (0.33 kg/d). Despite the lower starter intake for KPS, body weight and average daily gain did not differ between treatments. No significant difference was observed in the plasma concentrations of metabolites, except for β-hydroxybutyrate (BHB); BHB concentration was lower for KPS (216 μmol/L) than for CON (257 μmol/L). The area under the curve for plasma GLP-2 concentration was higher for KPS (54.1 ng/mL × d) than for CON (36.0 ng/mL × d). Additionally, the fecal score postweaning (1.19 and 1.48 for KPS and CON, respectively) and the number of days that calves developed diarrhea throughout the experimental period (2.50 d and 8.10 d for KPS and CON, respectively) were lower for KPS than for CON. These results indicate that feeding KP reduces the severity and frequency of diarrhea without adversely affecting growth performance. This could be attributed to the increased plasma GLP-2 concentration induced by higher NDF intake.

Growth performance and economic impact of Simmental fattening bulls fed dry or corn silage-based total mixed rations.

Bull-fattening diets in Europe and most developed countries around the world have traditionally been based on corn silage, starch-rich, and high-energy/ high-protein supplemental feeds. The impact of climate change on crop yields feed availability, and price volatility, requires new and adapted feeding strategies, including for fattening bulls. Therefore, the objective of this study was to compare the growth performance and economic impact of a representative, conventional corn silage-based (CONVL) total mixed ration, and a dry (DRY) total mixed ration (TMR) fed to Simmental bulls. For nine months (272days), 24 bulls (215±10kg BW) were randomly assigned to one of two TMR feeding groups (n=12 per group). The DRY-TMR was primarily characterised by the nutrient fibre source, exclusively based on straw and other by-products. The diets were formulated and balanced based on the Cornell Net Carbohydrate and Protein System. After 272days of fattening, bulls were slaughtered. Feed intake, average daily gain (ADG)/DM intake (DMI) ratio, and nutrient intake were affected by treatment, time, and their interaction (P<0.05). The treatment affected neither acid detergent lignin intake nor starch intake. Compared with CONVL bulls, animals fed DRY-TMR consumed more non-fibre carbohydrates and rumen undegradable neutral detergent fibre, showing lesser dry and fresh matter intake and less metabolisable energy and physically effective neutral detergent fibre intake. Despite differences in nutrient intake (P<0.05), particle size distribution between the two diets and growth performance were not different (P=0.45). Simmental bulls in both treatment groups reached target weight in a shorter time due to high ADG of 1.87kg (DRY-TMR) and 1.84kg (CONVL). Both treatments achieved a positive profit margin (598±28 €/bull). While total income per bull and dressing percentage did not differ between treatments, the substantially higher feed costs (P<0.01) of the DRY-TMR resulted in a higher (P=0.04) income over feed cost in favour of the CONVL treatment group. Despite the higher feed cost of DRY compared with CONVL diets, the better ADG/DMI ratio (P<0.01) of DRY-TMR contributed to lower absolute feed quantity requirements during the fattening period. Due to the positive profit margin and high ADG results, DRY-TMR solutions for fattening bulls based on straw and by-products can be considered a promising alternative feeding strategy.

The effects of ration particle size and live yeast supplementation on dairy cows performance under heat stress conditions

The objectives of this experiment were to evaluate the effects of ration particle size and dietary supplementation of live yeast (LY; Saccharomyces cerevisiae) on dry matter intake, milk yield and milk quality, apparent nutrient digestibility, ruminal fermentation parameters, and ruminal volatile fatty acids in dairy cattle under heat stress condition. Four multiparous Holstein dairy cattle in midlactation were fed 4 diets: high particle size (HPS), high particle size with 1g/d/cow LY (Levucell® Sc 10 ME Titan® CNCM I-1077 (10 × 109cfu/g) (HPS + LY), short particle size (SPS), short particle size with 1g/d/cow LY (Levucell® Sc 10 ME Titan® CNCM I-1077 (10 × 109cfu/g) (SPS + LY). Treatments were arranged in a 2 × 2 factorial within a 4 × 4 Latin square design. Decreasing ration particle size increased intakes of dry matter (DM), neutral detergent fiber (NDF) (P < 0.05) but decreased peNDF intake (P < 0.0001). Milk production and milk fat percentage were similar in cows. Cows fed SPS had lower milk protein percentage (P < 0.05). No treatments had any significant effect on apparent nutrient digestibility. Ruminal pH was higher in cows supplemented LY (P < 0.05). The ruminal total volatile fatty acid (VFA) concentration and percentage of VFAs were not significantly affected by ration particle size or dietary LY supplementing. Rectal temperature (oC) and respiratory rate (breaths/min) were similar between the groups. In conclusion, it may be concluded that decreasing ration particle size increased DM, and NDF intakes, without affecting milk yield or feed efficiency in cows exposed moderate heat stress.

Effects of substituting sericea lespedeza for lucerne on nutrient digestibility and utilization in feedlot lambs

The current study evaluated the effects of dietary increments of sericea lespedeza (SL, Lespedeza juncea var. sericea) as a substitute for lucerne (Medicago sativa L.) in lamb finishing diets on nutrient intake and digestibility, rumen fermentation, microbial nitrogen (N) supply, N balance, and N utilization efficiency. Following a completely randomized design, 25 Dohne Merino intact male lambs (4–5 months old) with an average initial weight of 28.2 ± 1.74 kg were equally assigned to five dietary treatments containing 0, 62.5, 125, 187.5 and 250 g SL per kg diet as replacement for lucerne in total mixed rations. The lambs were acclimatized to the diets and environment for 21 days before data collection during a 5-day period. Daily, the feed offered, refusals and total fecal matter were weighed to determine nutrient intake and digestibility, while urine was collected for the determination of urine nitrogen and purine derivatives excretion. At the end of the data collection period, lambs were humanely slaughtered, and the rumen was opened to determine ruminal pH, and collect representative samples of rumen fluid to determine ruminal fermentation parameters. Dietary increments of SL had no influence (P > 0.05) on the lambs’ nutrient intake except for neutral detergent fiber (aNDFom) intake which increased linearly (P ≤ 0.05) with SL inclusion. As SL increased in the diets, the apparent total tract digestibility of dry matter, organic matter, crude protein, aNDFom, and ether extract linearly declined (P ≤ 0.05). The concentrations of butyrate, valerate, and iso-valerate were quadratically (P ≤ 0.05) influenced by dietary inclusion of SL with maximum concentrations observed at the 125 g SL/kg inclusion level. Dietary inclusion of SL had no influence (P > 0.05) on purine derivatives excretion, microbial N supply, N balance, and N utilization efficiency. Overall, replacing lucerne with SL up to 250 g/kg in lamb finishing diets had no detrimental effects on nutrient intake and utilization.

Effects of palm kernel cake on nutrient utilization and performance of grazing and confined cattle: a meta-analysis.

A meta-analysis was conducted to evaluate the effects of dietary palm kernel cake inclusion (PKCInclusion) on the nutrient intake and digestibility, as well as on the performance of cattle under grazing and confined systems. Additionally, potential maximum safe levels (MSL) for PKCInclusion were explored for cattle under those systems using a broken-line approach. Overall, 22 studies for 85 treatment means and 747 experimental units were included in the dataset used for the meta-analysis in which, quantitative responses to increasing PKCInclusion levels were fitted using a mixed model, considering the study as a random effect. Additionally, all studies tested a treatment without the inclusion of PKC (PKCInclusion = 0g/kg DM) in the concentrate and total mixed ration fed to grazing and confined animals, respectively. In grazing animals, intake, and digestibility of dry matter (DM), as well as intake of total digestible nutrient (TDN) and digestibility of crude protein (CP) decreased linearly (P < 0.01) as PKCInclusion increased. Conversely, the intake and digestibility of neutral detergent fiber (NDF) increased linearly (P < 0.01). Additionally, the intake of CP showed a quadratic decreasing pattern (P < 0.01) with the increase in dietary PKCInclusion. In confined animals, intake of DM, CP, NDF, and TDN revealed quadratic patterns (P < 0.01) as PKCInclusion increased. The digestibility of DM, CP, NDF, as well as TDN concentration showed a linear decreasing pattern (P < 0.05) as PKCInclusion increased. For performance, data revealed that average daily gain (ADG) decreased linearly (P < 0.01) in grazing and confined animals with the increase in PKCInclusion. Feed efficiency (FE) decreased linearly (P < 0.01) in grazing animals, whereas it showed a linear increase (P < 0.05) in confined animals. Exploration of the quadratic relationships of intake of DM, CP, NDF, and TDN with PKCInclusion in confined animals revealed MSL values for PKC ranging from 85.56 ± 14.2 to 126.4 ± 14.7g PKC/kg DM. In grazing animals, exploration of the quadratic relationship of intake of CP with PKCInclusion, revealed an MSL value of 96.23 ± 9.01g PKC/kg DM. In conclusion, data revealed that the use of PKC in both confined and grazing systems reduces the nutrient utilization and performance of cattle in a dose-dependent manner without a maximum safe level that does not reduce animal performance.

Effect of waste mango silage on the in vitro gas production, in situ digestibility, intake, apparent digestibility, and ruminal characteristics in calf diets.

Mexico is the fifth largest producer of mangoes in the world. For the conservation of agro-industrial waste and crop residues, the ensiling technique has shown good results. This study aimed to evaluate the effect of increasing the level of mango silage (86% waste mango and 14% pangola grass hay) in calf diets on in vitro gas production, in situ digestibility, intake, apparent digestibility, and ruminal characteristics. The diets contained 0 (T0), 30 (T1), 45 (T2), and 60% (T3) mango silage. The partial (24, 48, and 72 h) and cumulative (72 h) biogas, CH4 production, and degradation were determined in the in vitro evaluation. In situ digestibility and estimators of fermentation kinetics of dry matter (DM) and organic matter (OM) were determined. Intake, apparent nutrient digestibility, and rumen parameters of calves (200 kg) were evaluated in a 4 × 4 Latin square design. Response to increased mango silage was calculated by linear and quadratic orthogonal contrasts. In vitro partial and cumulative biogas production decreased linearly (p < 0.05), and the partial and cumulative CH4 production did not show linear or quadratic contrast (p > 0.05); in vitro DM degradation, in vitro neutral detergent fiber degradation, and in vitro acid detergent fiber degradation showed a linear increase (p < 0.05). In situ dry matter digestibility (DMDis), in situ organic matter digestibility (OMDis), b, a + b, c, and effective digestibility (ED) of DMDis, a, a + b, c, and ED of OMDis increased linearly (p < 0.05). Dry matter intake, OM intake, and crude protein intake showed a linear increase (p < 0.05); NDF intake and ADF intake presented a quadratic behavior (p < 0.05). Apparent digestibility of DM, OM, CP, and hemicellulose, pH, N-NH3, total bacterial count, acetate, propionate, butyrate, volatile fatty acids, acetate: propionate ratio, cellulolytic bacteria, and protozoa did not present a linear or quadratic orthogonal effect (p > 0.05). The in vitro, in situ, and in vivo variables demonstrated that up to 60% mango silage can be used for the intensive fattening of calves in confinement.