Tropical grass silages with spineless cactus in diets of Holstein × Zebu heifers in the semiarid region of Brazil.

One of the factors that limit ruminant production in the semiarid region is the lack of roughage in the dry season. The management of forage plants adapted to edaphoclimatic conditions is a strategy to improve animal production. This study was conducted to examine the effects of biomass sorghum silage (BSS; Sorghum bicolor (L.) Moench) and BRS capiaçu grass silage (CGS; Pennisetum purpureum Schum) with or without spineless cactus (Opuntia spp.) in crossbred Holstein × Zebu heifers' diets on the intake, apparent digestibility of the nutrients and animal performance (e.g., final weight, daily weight gain) (experiment 1). Also, to evaluate the ruminal kinetics of dry matter (DM) and neutral detergent fiber (NDF) of roughages used in diets using two animals cannulated in the rumen (experiment 2). In experiment 1, ten heifers with an initial body weight of 200 ± 2.74 kg (mean ± standard deviation) and a mean age of 10 months were used. The animals were distributed in an experimental design in two simultaneous 5 × 5 Latin squares. Five experimental diets were used: diet 1, Volumax sorghum silage (VSS); diet 2, biomass sorghum silage (BSS); diet 3, BRS capiaçu silage (CGS); diet 4, biomass sorghum silage (60%) with spineless cactus (40%) (BSS + SC); and diet 5, BRS capiaçu grass silage (60%) with spineless cactus (40%) (CGS + SC). The diets were formulated with sorghum silage or BRS capiaçu grass silage with or without spineless cactus (roughage) and a maize- and soybean-based concentrate (75:25 roughage-to-concentrate ratio) on DM basis. The experiment lasted 105 days, divided into five periods of 21 days (17 days for the adaptation of the animals to the diets and management and 4 for data collection and samples). The diets containing CGS and CGS + SC resulted in lower dry matter intake (DMI; 5.61 kg day-1; P < 0.01), which was 19.4% lower than the diets with VSS, BSS, and BSS + SC (7.00 kg day-1). The BSS + SC and CGS + SC diets showed higher crude protein digestibility (P < 0.01) at 21.9% than the other treatments (Volumax, BSS, CGS). The different diets did not change the final weight or the daily weight gain of the heifers. The BRS 716 biomass sorghum silage and BRS capiaçu grass combined with spineless cactus increased (P < 0.05) the intake of nonfibrous carbohydrates and did not interfere (P > 0.05) with the final weight or average daily gain of the crossbred Holstein × Zebu heifers. The standardized potentially degradable fraction (Bp) of the NDF was 13.91% higher (P < 0.01) for BSS and BSS + SC (61.6%) compared to the others (53.0%). A diet based on BSS + SC is recommended for feeding crossbred heifers in the growing phase.

Effects of different banana crop wastes on nutrient intake and digestibility, microbial protein synthesis, feeding behavior, and animal performance of ¾ Holstein × Zebu heifers in a semiarid rangeland.

The objective of this study was to evaluate the use of banana crop wastes in diets of ¾ Holstein × » Zebu heifers on the intake and digestibility of nutrients, microbial protein synthesis, feeding behavior, and animal performance. Eight ¾ Holstein × » Zebu heifers were utilized with an average age of 18 ± 1.0 months and an average body weight (BW) of 298 ± 3.06 kg. The experiment was distributed in two simultaneous 4 × 4 Latin squares. The treatments were as follows: Diet 1 (SS)-sorghum silage as exclusive dietary roughage; diet 2 (SSL)-sorghum silage (50%) associated with 50% leaf hay of banana trees (on a DM basis); diet 3 (SSBP)-sorghum silage (50%) associated with 50% banana peel hay; and diet 4 (SSPS)-sorghum silage (50%) associated with 50% pseudostem hay of banana trees. The roughage:concentrate ratio was 75:25. The greatest dry matter intake (DMI; p < 0.01) was found in heifers that received the SS and SSBP diet, mean of 10.19 kg/day. The SS diet showed greatest dry matter digestibility (DMD; p < 0.01) and crude protein digestibility (CPD; p < 0.01). The concentration of total purines (p < 0.01) and absorbed purines (p < 0.01), microbial protein synthesis (p < 0.01), and microbial efficiency (p < 0.01) was higher in the SSBP diet in comparison with SS and SSL diets. The longest eating time was observed in animals that received the SSL diet, being 17.79% higher (p = 0.01) than the SSBP diet. The final BW (p = 0.39) and BW gain (p = 0.39) were similar, with averages of 319.84 kg and 1.08 kg/day, respectively. Biometric measurements were not altered as a function of bedtime (p > 0.05). Banana wastes can be used to feed ¾ Holstein × » Zebu heifers in partial replacement for sorghum silage as they do not alter the animals' weight gain and body development.

Effect of different roughage sources associated banana pseudostem hay on the nutritional and behavioral parameters and performance of F1 Holstein/Zebu lactation cows.

The objective of this study was to evaluate the association of pseudostem hay of banana trees of different roughages in the diet of F1 Holstein/Zebu cows on their nutrient intake and digestibility, nitrogen balance, microbial synthesis, ingestive behavior, and milk production. The experiment was distributed in two simultaneous 4 × 4 Latin squares. The treatments were as follows: diet 1-sorghum silage as exclusive dietary roughage; diet 2-sorghum silage (70%) associated with 30% pseudostem hay of banana trees (dry matter basis); diet 3-70% elephant grass with 30% pseudostem hay of banana trees (dry matter basis); and diet 4-70% sugarcane with 30% banana pseudostem hay (dry matter basis). The roughage/concentrate ratio was 75:25. The animals fed with sorghum silage presented 14.45% higher intake (p = 0.01) to that of animals fed hay and elephant grass. The diets containing silage and silage with hay showed digestibility of neutral detergent fiber corrected for ash and protein that was 57.75% higher (p < 0.01) than that of other diets. Cows fed elephant grass spent more time intake (p = 0.01). Diets did not influence milk yield (p = 0.47), and the milk yield corrected for 3.5 fat (p = 0.22), final weight (p = 0.06), and intake efficiency (p = 0.57), presenting a mean of 14.16 kg/day, 15.94 kg/day, 590 kg, and 0.9 kg of milk/kg of ingested dry matter, respectively. The utilization of pseudostem hay associated with other roughage can be an alternative to milk yield in F1 Holstein/Zebu cows.

Combinations of cactus pear with different roughage sources on the production, chemical composition, and milk fatty acid profile of F1 Holstein/Zebu cows.

The qualities of food, mainly of animal origin, have always been of concern to consumers. It is known that the composition of animals' diets can influence the composition of the foods produced, such as milk. Thus, the objective of this study was to evaluate diets with cactus pear in combination with different forages for F1 Holstein/Zebu cows on the chemical composition and fatty acid profile of milk. Two simultaneous 4 × 4 Latin squares were used in the experimental design. Four experimental diets were used: Diet 1, sorghum silage as the only roughage; Diet 2, sorghum silage combined with cactus pear in a proportion of 50% of the roughage (dry matter basis); Diet 3, elephant grass (Pennisetum purpureum cv. Roxo) as the only roughage; and Diet 4, elephant grass combined with cactus pear in a proportion of 50% of the roughage. The roughage:concentrate ratio was 75:25. The milk urea nitrogen was higher (16.08 mg/dL) in the milk of cows fed the diet with only elephant grass than that of milk from the other diet groups. The other analyzed variables of the chemical composition of milk were not influenced by the diets. However, there was a change in the sum of the saturated and monounsaturated fatty acids. The content of C16:0 fatty acid was higher and that of C18:0 was lower in the milk of cows fed the cactus pear diets than in that of cows fed the other diets. Higher levels of oleic acid were observed in the milk of cows fed with diets containing elephant grass than those in the milk of the cows in the sorghum forage groups. Conjugated linoleic acid (CLA) was higher in the milk of cows fed cactus pear than in that of the other cows. The combination of cactus pear with elephant grass or sorghum silage in the diet did not alter the chemical composition of milk. However, it influenced the fatty acid profile.

Nutritional and productive parameters of Holstein/Zebu cows fed diets containing cactus pear

Objective: This study ascertained effects of cactus pear in association with different roughage in the diet of F1 Holstein/Zebu cows on intake, nutrient digestibility, nitrogen balance, ingestive behavior and performance. Methods: Eight cows with 72 ± 11 days of lactation were used. The experimental design was simultaneous in two 4 x 4 Latin squares. Four experimental diets were used: Diet 1 - sorghum silage as exclusive roughage; Diet 2 - sorghum silage associated with cactus pear in a proportion of 50% of the roughage (dry basis); Diet 3 - elephant grass (Pennisetum purpureum cv. Roxo) as exclusive roughage; Diet 4 - elephant grass associated with cactus pear in a proportion of 50% of the roughage. The roughage:concentrate ratio was 75:25. Dry matter intake (P = 0.01) was higher with sorghum silage. Results: There were differences in dry matter intake (P = 0.01), crude protein (P <0.01), ether extract (P = 0.01), non-fibrous carbohydrates (P <0.01) and total digestible nutrients (P = 0.01) among the diets. Cactus pear in the diet reduced water intake by 44.52% (P < 0.01). The nitrogen balance was 59.71% and 27.49% lower in animals treated with exclusive sorghum silage and sorghum silage associated with cactus pear in relation to diets with elephant grass and elephant grass associated with cactus pear, respectively (P < 0.01). The diets did not influence the milk production (P = 0.70), 3.5% fat corrected milk production (P = 0.72) or feed efficiency (P = 0.61). Conclusion: The association of cactus pear with sorghum or elephant grass silage does not alter milk production, reduces the intake of dry matter and water and improves the digestibility of nutrients.

Efeito de níveis crescentes de ureia na alimentação de vacas sobre o rendimento, composição, perfil de ácidos graxos e sensorial do queijo minas frescal / Effect of increasing levels of urea in cows feed on yield, composition, fatty acid profile and sensory of minas fresh cheese

O estudo teve como objetivo avaliar a qualidade do queijo minas frescal processado com leite de vacas alimentadas com dietas com níveis crescentes de ureia (0; 33%; 66% e 100%, que corresponderam a 0, 0,92, 1,84 e 2,77% de PB na forma de NNP) em substituição ao farelo de soja. Foram utilizadas oito vacas F1 Holandês x Zebu, primíparas, com aproximadamente 150 dias de lactação ao início do experimento e produção média de 10kg de leite corrigido para 3,5 % de gordura dia -1 , em dois quadrados latinos 4 x 4, 4 animais, 4 dietas e 4 períodos experimentais. As amostras de leite de cada vaca, da ordenha da manhã e da tarde, foram coletadas e analisadas quanto à composição físico-química. No terceiro dia de coleta, o leite obtido de cada tratamento foi processado para fabricação do queijo minas frescal. Os produtos foram analisados quanto às suas características físico-químicas, textura, rendimento, perfil de ácidos graxos, e aceitação sensorial. Não houve efeito da adição dos níveis crescentes de ureia em substituição ao farelo de soja na dieta das vacas para todos os parâmetros que indicam a qualidade dos queijos analisados. Dessa forma, conclui-se que a substituição total da ureia pelo farelo de soja na dieta com o intuito de reduzir custo de alimentação não altera a qualidade na produção do queijo minas frescal.

The study aimed to evaluate the quality of the minas fresh cheese processed with milk cows fed diets with increasing levels of urea (0, 33%, 66% and 100%, corresponding to 0, 0.92, 1.84 and 2.77% crude protein in the form of NPN) replacing soybean meal. Eight cows F1 Holstein x Zebu, gilts, with approximately 150 days of lactation to the beginning of the experiment and average production of 10 kg of milk corrected to 3.5% fat day-1, in two Latin squares 4 x 4, 4 animals, 4 diets and 4 experimental periods. Samples of milk from each cow, the milking morning and afternoon, were collected and analyzed for physical and chemical composition. On the third day of collection, the milk obtained from each treatment was processed for the production of minas fresh cheese. Products were analyzed as to their physical and chemical characteristics, texture, yield, fatty acid profile, and sensory acceptance. There was no effect of the addition of increasing levels of urea in substitution of soybean meal in the diet of cows to all the parameters that indicate the quality of cheeses analyzed. Thus, it is concluded that the total replacement of soybean meal by urea in order to reduce power cost does not change the quality in the production of minas fresh cheese.