Effects of supplementing cassava root silage to grazing dairy cows on nutrient utilization, milk production and composition in the tropics.

The current study evaluated the effects of supplementing cassava root silage (CRS) to dairy cows grazing on Megathyrsus maximus cv Mombasa on nutrient intake and digestibility, as well as on milk production and composition. Ten primiparous Girolando cows with average body weight ± (SEM) of 373.45 ± (63.55) kg were used in a replicated 5 × 5 Latin square. Animals were subjected to five treatments: (I) grazing cows without supplementation (WCS); (II) grazing cows provided with 5 kg DM of supplement without CRS (0 g/kg DM of CRS) or including (III) 260, (IV) 520, and (V) 780 g/kg DM of CRS. Statistical analyses were performed using the PROC MIXED of SAS with significance at P < 0.05. Intake of neutral detergent fiber (NDF) and ether extract decreased (P < 0.01), while intake of non-fiber carbohydrates increased (P < 0.01), with increased CRS in the diets. Total DM intake and digestibility of DM, and digestibility of nutritional components were lower (P < 0.03) in WCS animals compared to supplemented animals, except for intake and digestibility of NDF, which was the opposite. Milk yield (MY) and fat corrected milk (FCM), as well as all milk components were unaffected (P > 0.05) by CRS inclusion. In contrast, MY, FCM, protein, lactose, casein, and non-fat milk solids (NFMS) were greater for animals that received supplementation (P < 0.05), compared to animals WCS. Milk fat and total dry extract (TMS) did not differ (P > 0.11) between two groups. In conclusion, CRS may be a potential corn meal replacer in the supplement of dairy cows under tropical conditions.

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 = 0 g/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 ± 14.7 g PKC/kg DM. In grazing animals, exploration of the quadratic relationship of intake of CP with PKCInclusion, revealed an MSL value of 96.23 ± 9.01 g 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.

Carcass traits and meat characteristics of grazing Nellore cattle submitted to different supplementation strategies in the tropics.

This study explored the effects of different supplementation strategies during the dry and rainy seasons in the tropics on the carcass traits and meat quality of Nellore cattle produced under grazing conditions. Additionally, a cost assessment of the supplementation strategies was conducted to define the most suitable ones from an economic standpoint. Twenty-eight non-castrated male animals (18 months) with an initial body weight of 327.9 ± 4.2 kg were used. The animals were equitably distributed in a randomized complete design thorough four supplementation strategies as follows: (i) mineral supplementation (MS) in both dry and rainy seasons (MS/MS), (ii) MS during the dry season and concentrate supplementation (CS) during the rainy season (MS/CS), (iii) CS during the dry season and MS during the rainy season (CS/MS), and (iv) CS in both dry and rainy seasons (CS/CS). Thereafter, carcass traits, primary carcass cut yields, meat quality traits, and chemical composition of the meat of cattle produced across different supplementation strategies were determined. Data revealed that animals under CS/CS showed the greatest (P < 0.01) hot carcass weights among the other supplementation strategies evaluated. Conversely, supplementation strategy did not affect (P > 0.10) the carcass traits (the ribeye area, final pH, and forequarter), meat quality traits (shear force, myofibrillar fragment index, sarcomere length, and color), and meat chemical composition (crude protein, fat, and moisture) of the animals. A cost assessment of the supplementation strategies revealed that CS/CS had the highest production costs. Nevertheless, CS/CS had the greatest income and profit, while MS/MS had the lowest ones. In conclusion, data suggest that cattle grazing on tropical forage under CS during at least one season (i.e., dry or rainy) produce similar meat quality traits and chemical composition of meat to those observed for animals under CS in both seasons. Additionally, the last supplementation strategy revealed the greatest profit indicators among the other explored.

Nutrient utilization, performance, and milk fatty acid composition of grazing cows fed supplements with babassu coconut.

This study evaluated the effects of dietary inclusion of cracked babassu coconut (CBC) in the supplement on nutrient utilization, performance, and milk fatty acid (FA) composition of dairy cows grazing Megathyrsus maximus cv. Mombasa. Five multiparous Holstein × Zebu mid-lactation cows (125 ± 16.5 days in milk) were assigned to five dietary treatments (replacement of 0%, 20%, 40%, 60%, and 80% of ground corn with CBC, on a dry matter (DM) basis) in a 5 × 5 Latin square design. The intake of DM from the supplement, crude protein (CP), non-fiber carbohydrate (NFC), fat (ether extract (EE)), and total digestible nutrients (TDNs) decreased linearly (P < 0.05), while the intake of DM from forage increased linearly (P < 0.05), with the increase in CBC inclusion in the supplement. Conversely, total DM intake was unaffected (P > 0.05). The DM, NFC, EE, and TDN digestibility decreased linearly (P < 0.05), while organic matter (OM) digestibility decreased in a quadratic fashion (P < 0.05), as CBC inclusion in the supplement increased. Nevertheless, digestibility of CP was unaffected (P > 0.05). Milk yield and composition (lactose, fat, protein, casein, and majority of FA) showed a linearly decreasing pattern (P < 0.05) with the increasing of CBC inclusion. However, proportions of trans-vaccenic acid, rumenic acid, total monounsaturated FA, and odd- and branched-chain FAs increased linearly (P < 0.05). On the opposite, total saturated FA (SFA) and the n-6:n-3 FA ratio in milk fat decreased linearly (P < 0.01). Hence, replacement of corn meal with CBC up to 80% in the supplement decreases nutrient intake and digestibility, as well as milk yield response in grazing dairy cows. However, CBC inclusion may enhance the nutritional properties of milk fat.

Multivariate relationship between the nitrogen excretion and the protein and fiber utilization in hair sheep fed Mombasa grass silage mixed with açai palm seeds.

This study evaluated the multivariate relationship among the crude protein (CP) intake and digestibility, the neutral detergent fiber (NDF) intake and digestibility, and the nitrogen excretion in hair sheep fed Mombasa grass silage mixed with açai palm seeds using canonical correlation analysis (CCA). For this purpose, a dataset was constructed using the information derived from a metabolic experiment with Santa Ines sheep (BW ± SE: 33.9 ± 1.37 kg) allocated into a 5 × 5 Latin square. The following two multivariate relationships were explored using CCA: (1) the N in both feces (Nfeces) and urine (Nurine) (canonical variate U) versus the intake of both CP (CPI) and NDF (NDFI) (canonical variate V). (2) the Nfeces and Nurine (canonical variate W) versus the digestibility of both CP (CPD) and NDF (NDFD) (canonical variate Z). Canonical loadings for relationship No. 1 revealed that Nfeces (0.971) and Nurine (- 0.249) had a positive and negative correlation, respectively, with U. Both CPI (0.960) and NDFI (0.997) had a positive and similar correlation with V. Regarding relationship No. 2, both Nfeces (0.860) and Nurine (0.500) had a positive correlation with W. Conversely, both CPD (- 0.910) and NDFD (- 0.889) had a negative and similar association with Z. In conclusion, our data showed that when a multivariate approach is used, an increase in both CPI and NDFI produces an increase in Nfeces, as well as a decrease in Nurine. Additionally, a decrease in both CPD and NDFD produces an increase in both Nfeces and Nurine.

Intake, digestibility, and milk yield response in dairy buffaloes fed Panicum maximum cv. Mombasa supplemented with seeds of tropical açai palm.

The use of alternative tropical feeds, such as açai seeds, under tropical pasture production systems, may help to optimize buffalo milk production mainly in the Amazon region, which has the largest worldwide açai production. This study evaluated the effects of dietary inclusion of açai palm seeds in the supplement on nutrient utilization and milk yield response of lactating buffaloes grazing Panicum maximum cv. Mombasa. The treatments comprised four levels of açai palm seeds (0, 198.4, 396.8, and 595.2 g/kg of dry matter) and a treatment without concentrate supplementation (WCS). Five half-breed Murrah female buffaloes with average body weight ± (SEM) of 577 ± (20.4) kg were used in a 5 × 5 Latin square design. There was no effect of the inclusion of açai palm seeds on the total dry matter and nutrient intakes (P>0.05). The digestibility of dry matter, organic matter, neutral detergent fiber, and total digestible nutrients showed a linear decreasing pattern (P<0.05), whereas the digestibility of crude protein demonstrated a quadratic pattern, as açai palm seed inclusion level increased (P<0.05). Milk production demonstrated a quadratic pattern as açai palm seed inclusion increased (P<0.05). There was no effect of açai palm seed inclusion on milk composition (P>0.05), except for fat (%), protein (%), and the concentration of total dry extract (P<0.05). There was no difference in nutrient intake and digestibility and milk performance, between supplemented and WCS animals (P>0.05). In conclusion, the inclusion of açai palm seeds at 198.4 g/kg DM in the supplement of grazing buffaloes improves the digestibility of crude protein and milk production, without detrimental effects on nutrient intake. Also, açai palm seeds may be a potential replacer of Panicum maximum cv. Mombasa under tropical conditions.

Production, chemical composition, and economic viability of Minas Frescal cheese from buffaloes supplemented with açai seed.

We aimed to evaluate the chemical composition, production yield, and economic viability of Minas Frescal cheese produced with milk from buffaloes supplemented with açai seed as a substitute for corn meal. The experiment used five Murrah crossbred buffaloes with a mean body weight of 577 ± 20.4 kg, maintained under Megathyrsus maximus cv. Mombaça grazing in a 5 × 5 Latin square design. The treatments comprised four concentrate supplements, in which açai seed replaced corn meal at 0, 33, 66, and 100% substitution, and a control with no concentrate supplementation. Replacement of corn meal with açai seed in buffalo diet had no effect on chemical composition of produced cheese (P > 0.05) nor was there any difference in chemical composition between the control group and animals supplemented with concentrate (P > 0.05). The adjusted cheese yield (kg cheese/cow/day) demonstrated a quadratic pattern with maximum production at 33% açai seed substitution (P < 0.05). Hence, the profitability index (percentage of gross revenue) was greatest at this replacement level. In conclusion, 33% açai seed replacement of corn meal in the supplement of buffalo under a grazing regime improved the individual yield of Minas Frescal cheese without changing its chemical composition.