Search Results (12)

For cattle raised on tropical grass pastures, it is essential to explore strategies that circumvent climatic seasonality that affect forage availability and quality. We hypothesize that the intensification of grazing systems, with rotational and deferred methods, combined with ammonium nitrate or urea supplementation, are excellent strategies to increase ruminal efficiency and animal productivity. For this purpose, 8 cattle with cannulas were distributed in rotational and deferred grazing systems, supplemented with urea or ammonium nitrate, and evaluated throughout the four seasons of the year over a period of two years. Dry matter intake and digestibility were measured using indigestible neutral detergent fiber, titanium dioxide and chromium oxide markers. Ruminal kinetics and degradability of DM and nutrients were measured using the nylon bag technique. Urine parameters were used to estimate microbial nitrogen compounds synthesis and efficiency of microbial protein synthesis. The rotational grazing improves NPN intake, NDF and ADF digestibility, and gross energy. Ammonium nitrate supplementation showed improved efficiency in microbial protein synthesis without negatively affecting feed intake, positioning it as a valuable nitrogen source for grazing cattle. Full article

Total mixed ration silage has been used as a strategy to optimize the use of dry and wet feed in ruminant feeding. Another promising technique is silage reallocation, which allows producers to divide the ensiled material in large silos into smaller units that can be easily transported and marketed. Thus, this study aimed to improve food preservation through the development of total mixed rations (TMRs) based on relocated sorghum silage (RSS) and cactus pear for sheep diets. A completely randomized design was used with five treatments (0, 15, 25, 30, and 35% RSS inclusion on a dry matter basis) and five replicates. Ninety days after ensiling, the silos were opened. The fermentation characteristics, nutritional aspects, aerobic stability, and microbial populations of TMR silages were evaluated. The inclusion of RSS showed a quadratic effect on pH, density, permeability, lactic acid bacteria and yeast counts, and total carbohydrates (p < 0.05). It reduced gas and effluent losses, porosity, ammonia nitrogen, buffer capacity, ash, crude protein, ether extract, and non-fibrous carbohydrates (p < 0.05) while increasing dry matter, neutral and acid detergent fiber, hemicellulose, and cellulose contents (p < 0.05). There was an interaction effect between the levels of RSS inclusion and exposure times to air on CO₂ and dry matter content (p < 0.05). Regarding carbohydrate fractionation, there was a reduction in fraction A + B1 (non-fibrous carbohydrates) and an increase in fractions B2 (fibrous carbohydrates from the cell wall and of slow ruminal availability, susceptible to the effects of the passage rate) and C (indigestible neutral detergent fiber) (p < 0.05). For protein fractionation, a quadratic effect was observed for fractions A (non-protein nitrogen) and C (insoluble protein, indigestible in the rumen and intestine), an increase in fraction B1 (soluble protein rapidly degraded in the rumen) + B2 (insoluble protein with intermediate degradation rate in the rumen), and a reduction in fraction B3 (insoluble protein with slow degradation rate in the rumen) (p < 0.05) as RSS levels increased. Under the experimental conditions, it is recommended to include up to 30% RSS in the total mixed ration silage to improve microbiological characteristics, reduce gas and effluent losses, and increase dry matter recovery and nutritional aspects of silage when associated with cactus pear. Full article

Objective: The experiment was conducted to determine the apparent or standardized ileal digestibility (AID or SID) of crude protein (CP) and amino acids (AA) in 10 rapeseed cake samples fed to pigs, and to construct predictive models for the SID of CP and AA based on the chemical composition of rapeseed cakes. Methods: Twenty-two cannulated pigs (initial body weight: 39.8 ± 1.2 kg) were assigned to two 11 × 3 incomplete Latin square designs, including an N-free diet and 10 diets containing rapeseed cake. Each experimental period included 5 days of adaptation and 2 days of ileal digesta collection. Titanium dioxide (TiO₂) was added at 0.3% to all the diets as an indigestible marker for calculating the ileal CP and AA digestibility. Results: The coefficients of variation (CV) of the content of crude fat (EE), crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF), and total glucosinolates (TGS) in 10 samples of rapeseed cake were greater than 10%. The standardized ileal digestibility (SID) of crude protein (CP), lysine (Lys), methionine (Met), threonine (Thr), and tryptophan (Trp) in rapeseed cake was 73.34% (61.49 to 81.12%), 63.01% (41.41 to 73.10%), 69.47% (50.55 to 88.16%), 79.61% (74.41 to 87.58%), and 94.43% (91.34 to 97.20%), respectively. The best prediction equations for SID_CP, SID_Lys, and SID_Val were as follows: SID_CP = 90.124 − 0.54NDF (R² = 0.58), SID_Lys = 100.107 − 1.229NDF (R² = 0.94), and SID_Val = 151.012 − 2.990TGS (R² = 0.57). Conclusion: Overall, great variation exists among the 10 rapeseed cakes, and the NDF, TGS, and heating temperature can be used as the key predictors for the SID of CP and AA. Full article

The consumption of maternal feces (coprophagy) is commonly observed in healthy foals and is a proposed contributor to microbial colonization of the foal’s gastrointestinal tract (GIT). This study investigated the role of coprophagy in the establishment of fibrolytic bacteria in the foal GIT. Nine thoroughbred mares were dosed with chromic oxide, an indigestible marker, as a method to detect the occurrence of coprophagy by their foals. Foal fecal samples were collected from 12 h to 21 d after birth to measure chromic oxide and neutral detergent fiber (NDF) and to enumerate cellulolytic bacteria using culture-based techniques. Milk yield was estimated at 7 and 14 d postpartum. Coprophagy was detected as early as 3 d after birth and detected in all foals by 7 d of age. There were strong relationships between coprophagy and cellulolytic bacteria and NDF in foal feces at 7 d of age (r = 0.9703 and r = 0.7878, respectively; p < 0.05). Fecal NDF and chromic oxide concentrations were negatively related to milk yield (r = –0.8144 and r = –0.6966, respectively; p < 0.05), suggesting milk availability affected the incidence of coprophagy. Based on the relationships identified, maternal feces are an important source of fiber and live microbes for the foal, contributing to the development of the microbial community. Full article

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. Full article

To improve the utilization efficiency of rape straw, anaerobic calcium oxide (CaO) alkalization was conducted, and advanced molecular spectroscopy was applied, to detect the internal molecular structural changes. Rape straw was treated with different combinations of CaO (3%, 5%, and 7%) and moisture levels (50% and 60%) and stored under anaerobic conditions. We investigated the carbohydrate chemical constituents, the ruminal neutral detergent fiber (aNDF) and acid detergent fiber (ADF) degradation kinetics, and the carbohydrate molecular structural features. CaO-treated groups were higher (p < 0.05) for ash, Ca, non-fiber carbohydrate, soluble fiber, and the ruminal degradability of aNDF and ADF. In contrast, they were lower (p < 0.05) for the contents of aNDF, ADF, and indigestible fiber. With CaO levels rising from 3% to 7%, the content of aNDF and ADF linearly decreased (p < 0.05). CaO treatment and anaerobic storage changed the molecular characteristics, including structural parameters related to total carbohydrates (TC), cellulosic compounds (CEC), and structural carbohydrates (STC). Alterations in cellulosic compounds’ spectral regions were highly correlated with the differences in carbohydrate chemical constituents and the ruminal digestibility of rape straw. In summary, CaO treatment and anaerobic storage altered the molecular structural parameters of carbohydrates, leading to an enhancement in the effective degradability (ED) of aNDF and ADF in rape straw. From the perspective of processing cost and effectiveness, 5% CaO + 60% moisture could be suggested as a recommended treatment combination. Full article

The objective of this study was to evaluate the use of calcium oxide (CaO) on the nutritive profile, digestibility, and carbohydrate fractionation of three sugarcane (Saccharum officinarum hybrids) genotypes: IAC-862480, SP-791011, and CTC-3. Four CaO levels (0, 1.5, 3.0, and 4.5% on a fresh matter basis) were used in a 3 × 4 factorial scheme, whose factors were the three sugarcane genotypes and the four levels of calcium oxide. The chemical composition, carbohydrate fractionation, total digestible nutrients, and in vitro dry matter digestibility (IVDMD) were evaluated. The chemical composition of the treated sugarcane was affected by the genotype and the use of CaO. The CTC-3 genotype showed lower values of crude protein (CP), ether extract (EE), neutral detergent fiber (NDFap), acid detergent fiber (ADF), and phosphorus (p < 0.01) contents when compared to the IAC-862480 genotype. A decreasing linear effect (p < 0.01) of CP, EE, ADF, lignin, cellulose, non-fibrous carbohydrates, and total digestible nutrients was observed with increasing levels of CaO. A quadratic effect was observed for the contents of DM, organic matter, NDFap, and hemicellulose when the sugarcane was treated with CaO (p < 0.05). The treatment of sugarcane with CaO resulted in the reduction (p < 0.05) in the indigestible fraction of sugarcane. The IAC-862480 and SP-791011 genotypes showed a better nutritional profile compared to the CTC-3 genotype. On the other hand, CaO treatment improved IVDMD and decreased the non-digestible fraction of sugarcane. Full article

The objective of this study is to investigate the potential of novel neural network architectures for measuring the quality and quantity parameters of silage grass swards, using drone RGB and hyperspectral images (HSI), and compare the results with the random forest (RF) method and handcrafted features. The parameters included fresh and dry biomass (FY, DMY), the digestibility of organic matter in dry matter (D-value), neutral detergent fiber (NDF), indigestible neutral detergent fiber (iNDF), water-soluble carbohydrates (WSC), nitrogen concentration (Ncont) and nitrogen uptake (NU); datasets from spring and summer growth were used. Deep pre-trained neural network architectures, the VGG16 and the Vision Transformer (ViT), and simple 2D and 3D convolutional neural networks (CNN) were studied. In most cases, the neural networks outperformed RF. The normalized root-mean-square errors (NRMSE) of the best models were for FY 19% (2104 kg/ha), DMY 21% (512 kg DM/ha), D-value 1.2% (8.6 g/kg DM), iNDF 12% (5.1 g/kg DM), NDF 1.1% (6.2 g/kg DM), WSC 10% (10.5 g/kg DM), Ncont 9% (2 g N/kg DM), and NU 22% (11.9 N kg/ha) using independent test dataset. The RGB data provided good results, particularly for the FY, DMY, WSC and NU. The HSI datasets provided advantages for some parameters. The ViT and VGG provided the best results with the RGB data, whereas the simple 3D-CNN was the most consistent with the HSI data. Full article

The aim of this study was to evaluate the effect of replacing Tifton-85 hay (Cynodon spp. cv. Tifton 85) with 0, 150, 300, 450 and 600 g/kg dry matter (DM) of spineless cactus (SC, Nopalea cochenilifera Salm-Dyck) plus urea and ammonium sulfate (UAS; 9:1) on DM, digestible organic matter (DOM) and indigestible neutral detergent fiber (iNDF) intakes, as well as ruminal fermentation, N-balance, and microbial protein supply (MPS). Five rumen-fistulated and cannulated crossbred wethers, weighing 43.8 ± 5.80 kg, were randomized in a 5 × 5 Latin square design. Isonitrogenous diets (14% crude protein) were supplied with a roughage/concentrate ratio of 70:30. The DOM intake, N-retained, and MPS showed quadratic responses (p < 0.05), with maximum values estimated at the levels of SC+UAS of 414, 438 and 418 g/kg DM, respectively. Rumen pH and ammonia nitrogen, iNDF intake, N-urinary excretion, and serum urea and plasma ammonia reduced linearly (p < 0.05) with increasing SC+UAS inclusion. Ruminal acetate and propionate concentrations increased linearly with increasing SC+UAS inclusion. In wethers fed diets with a roughage/concentrate ratio of 70:30, roughage constituted of a SC+UAS/hay (Tifton-85) ratio of 41:29 is recommended in order to maximize the DOM intake, N-retention, and MPS. Full article

Three main crop straws including corn straw (Zea mays, CS), rice straw (Oryza sativa, RS), and wheat straw (Triticum aestivum, WS), and two forages including alfalfa hay (Medicago sativa, AH) and corn silage (Zea mays, CSil) were analyzed in order to compare their ruminal degradability, indigestible neutral detergent fiber (iNDF), intestinal digestibility (ID), and their total-tract digestibility (TTD) of crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) using both an in situ nylon bag technique and a mobile nylon bag technique. The forage samples were incubated in the rumen for 6, 12, 16, 24, 36, 48, 72, and 288 h, respectively, to determine their ruminal degradability. Prior to intestinal incubation, forage samples were incubated in the rumen for 12 h and 24 h to determine the ruminal degradable content of CP, NDF, and ADF, respectively, and for 288 h to determine their iNDF₂₈₈ content. Residues from the ruminal undegradable fractions (12 h for CP, 24 h for NDF and ADF) were subsequently inserted into the duodenum through a cannula to determine their intestinal digestible content. Here, the TTD of CP, NDF, and ADF were determined as the ruminal degradable content + intestinal digestible content. The results showed that AH had the highest iNDF_2.4 (calculated as acid detergent lignin content × 2.4) and iNDF₂₈₈ values (379.42 and 473.40 g/kg of NDF), while CS and CSil had the lowest iNDF_2.4 values (177.44 and 179.43 g/kg of NDF). The ruminal degradability of CP, NDF, and ADF for CS, RS, and WS were lower than those of AH and Csil during the first 48 h of incubation. The potential degradation fraction of CP, NDF, and ADF for CSil was the highest; CS, RS, and WS were intermediate; and AH was the lowest (p < 0.05). CS, RS, and WS had a lower intestinal digestibility with respect to their rumen undegradable content of NDF (p < 0.05), and lower TTD of CP, NDF, and ADF (p < 0.05) compared to AH and CSil. General regression equations with satisfactory accuracy (R² ≥ 0.828) were derived to predict iNDF₂₈₈ and TTD based on their chemical compositions and the ruminal degradation kinetics of different forages. Incorporating this information into rations could improve our ability to optimize main crop straws utilization and milk production. Full article

Nitrogen (N) management affects herbage production and chemical composition; however, information on the impact of tropical herbage on N and carbohydrate fractions is scarce. A two-year study was conducted to investigate the potential use of pintoi peanut (Arachis pintoi) compared with N fertilization of palisade grass (Brachiariabrizantha cv. Marandu) by evaluating the herbage chemical composition (fractionation of protein and carbohydrate), herbage mass and accumulation rate, herbage disappearance rate, and stocking rate of pastures. The experiment was conducted in a completely randomized design with three treatments, and four replications (paddocks) were used with twenty-one non-lactating crossbred dairy heifers. Treatments consisted of pastures of palisade grass without a N source (control), fertilized with urea (150 kg/ha/year; fertilized), or mixed with pintoi peanut (mixed). Inclusion of the legume increased concentrations of fractions A (p = 0.009), which is the soluble N compound, and B3 (p < 0.001), which is slowly degraded true protein, compared with pastures fertilized with N and non-fertilized pastures. Nitrogen fertilization increased fraction B1 + B2 (p = 0.046), mainly true proteins, and decreased fraction C (p = 0.0007), indigestible protein, and neutral detergent fiber concentrations (p = 0.0003), contributing to increasing the nutritive value of the herbage. Additionally, N fertilization increased herbage mass (p = 0.004) and herbage allowance (p = 0.0001). Both N fertilization and biologically fixed N increased herbage allowance (p = 0.02) and accumulation rate (p = 0.02), as well as the crude protein content of herbage (p < 0.0001) compared with non-fertilized pastures. Nitrogen fertilization increased true protein and decreased indigestible protein of herbage and promoted a greater herbage mass production, while the inclusion of legumes increased soluble protein and decreased the slowly degraded true protein of herbage. Both N management strategies increased herbage allowance and accumulation rate. Full article

This study aimed to evaluate the effects of optimal carbohydrase mixture (OCM) on macronutrients and amino acid digestibility and the digestible energy (DE) in growing pigs fed the corn-soybean meal-based diet (CSM) and the wheat-soybean meal-based diet (WSM). A total of 36 ileal-cannulated pigs (50.9 ± 4.9 kg initial body weight) were allotted to four dietary treatments randomly, which included CSM and WSM diets, and two diets supplied with corresponding OCM. These OCMs were screened using an in vitro method from our previous study. After the five day adaptation period, fecal samples were collected from d six to seven, and ileal digesta samples were collected on d 8 and 10. Chromic oxide was added as an indigestible marker. The results show that the addition of OCM improved the apparent ileal digestibility (AID) of dry matter (DM), ash, carbohydrate (CHO), neutral detergent fiber, and gross energy (GE) and the apparent total tract digestibility (ATTD) of DM, CHO, and GE in CSM diet (p < 0.05), but reduced the apparent hindgut disappearance (AHD) of DM in CSM diet (p < 0.05). The ATTD of DM, crude protein (CP), ether extract (EE), ash, and GE and the AHD of DM, CP, EE, ash, CHO, and GE in WSM diet were improved by the OCM addition (p < 0.05), whereas the AID of DM, CP, ash, CHO, and GE were decreased (p < 0.05). The respective DE contents in CSM and WSM diets were increased from 15.45 to 15.74 MJ/kg and 15.03 to 15.49 MJ/kg under the effects of OCM (p < 0.05). Similar to the trend of AID of CP, the OCM addition increased the AID and standardized ileal digestibility (SID) of Ile, Thr, and Cys in CSM diet, but decreased the AID and SID of Ile, Phe, Thr, Val, Ala, Pro, Ser, and Tyr in WSM diet. In conclusion, the OCMs screened by an in vitro method could improve the total tract nutrient digestibility and DE for pigs fed corn-based diet or wheat-based diet but had inconsistent effects on the ileal digestibility of nutrients and energy. Full article