Effects of replacing ground corn with Nopalea cochenillifera meal on the intake, performance, and economic viability of grazing steers.

The objective of this study was to evaluate the effects of replacing different levels of spineless-cactus meal instead of ground corn on supplements for crossbred steers grazing in Urochloa brizantha cv. Marandú pastures. Forty crossbred steers with an average body weight (BW) of 261 ± 7.46 kg were distributed in a completely randomized design. In supplements, the ground corn grain was substituted with 0%, 30%, 60%, and 90% spineless-cactus meal. The substitution of spineless-cactus meal instead ground corn promoted a linear decrease in the ether extract (EE; P = 0.03) and non-fibrous carbohydrates (NFC; P < 0.01) intakes. The apparent digestibility of EE was influenced (P < 0.05) showing a linear decrease. The apparent digestibility of NFC had a quadratic effect (P = 0.03). For the neutral detergent fiber corrected for ash and protein, the apparent digestibility increased linearly (P = 0.01). The average daily gain showed a quadratic effect (P < 0.01), with a maximum response estimated at 44.94% (1055.52 g/day) substitution with spineless-cactus meal for ground corn. The cost per animal per period and the cost per hectare decreased linearly (P < 0.01). The revenue, net revenue, exchange rate, and monthly revenue of the activity showed quadratic responses to the spineless-cactus meal supplements (P < 0.01), with maximum effects at 44.99%, 47.46%, 61.25%, and 57.35%, respectively. The substitution with up to 44.94% of spineless-cactus meal for ground corn provided daily gains, increased the feed conversion, and was favorable as a cost to the production system. Moreover, the profitability increased with maximum animal performance and improved use of fiber from pastures.

Inclusion of palm kernel cake in the supplement reduces nutrient digestibility but does not interfere with the performance of steers finished on tropical pasture.

The aim of this study was to evaluate the effect of increasing inclusion levels of palm kernel cake (PKC) in the supplement of steers finished on a Urochloa brizantha cv. Marandu pasture on intake, digestibility, feeding behavior, weight gain, and carcass traits. Forty 1/2 Holstein × 1/2 Zebu crossbred steers with an average body weight of 352.80 ± 3.32 kg, at 36 months of age, were supplemented with concentrate at 0.4% of their body weight. Four treatments were formulated (supplement containing 0, 15, 30, or 45% PKC, dry matter [DM] basis) and the animals were monitored for 240 days, weighed, and slaughtered. The inclusion of PKC in the supplement did not influence the intakes of total DM, crude protein, or neutral detergent fiber, but increased (P < 0.05) ether extract intake and reduced (P < 0.05) non-fibrous carbohydrate intake. The apparent digestibility of DM, crude protein, and neutral detergent fiber decreased (P < 0.05), whereas intake and rumination efficiencies by the dietary treatments. Average daily gain, carcass weight, and backfat thickness did not change in response to the inclusion of PKC in the supplement. We recommend the inclusion of 45% palm kernel cake in the concentrate of steers supplemented at 0.4% of their body weight and finished on Urochloa brizantha cv. Marandu pasture.

Ingestive behaviour of steers grazing Brachiaria brizantha cultivar Marandu and in feedlot in Brazil.

The objective of this study was to evaluate the ingestive behaviour of steers grazing Brachiaria brizantha cv. Marandu and in feedlot regimen in Brazil. Fifty crossbred steers, with an average weight of 275 ± 8.18 kg, were distributed in a completely randomised design with five treatments and ten replicates per treatment (mineral supplementation, nitrogen supplementation, and concentrate supplementation at 0.1 and 0.2% of body weight and under feedlot conditions). Ingestive behaviour was assessed every 5 min for 24 h. No difference (P > 0.05) was found for grazing time among grazing systems. Conversely, rumination, idle, feeding, and chewing times showed differences (P < 0.05) only for feedlot animals. The time spent feeding at the trough was higher (P < 0.05) in animals receiving concentrate supplementation. The bite rate and the number of bites per day were similar (P > 0.05) among grazing systems. Feed and rumination efficiencies of dry matter and neutral detergent fibre corrected for ash and protein showed differences (P < 0.05) only in feedlot animals. Therefore, ingestive behaviour of steers varies with the raising system. Overall, feedlot animals showed better performance than grazing animals did, most likely due to longer rest periods.

Increasing levels of supplementation for crossbred steers on pasture during the dry period of the year.

The aim of this study was to evaluate the effect of increasing concentrate supplementation levels on the intake, nutrient digestibility, and performance of crossbred steers during the dry period of the year. The experiment was developed on Princesa do Mateiro farm, in the municipality of Ribeirão do Largo, located in the southwest region of Bahia State, Brazil. Forty uncastrated male crossbred (½ Holstein-Zebu) steers with an average body weight (BW) of 232.55 ± 24.97 kg were distributed into four treatments in a completely randomized design with ten replicates. The animals were managed in an experimental area formed by Brachiaria brizantha cv. Marandu, in an intermittent grazing system. Treatments consisted of the following supplementation levels: 0.2% BW, with 60% crude protein (CP); 0.3% BW, with 40% CP; 0.4% BW, with 30% CP; and 0.5% BW, with 24% CP. The intakes of forage dry matter in kg/day and %BW and neutral detergent fiber corrected for ash and protein (NDFap) in %BW decreased linearly, whereas the intake of non-fibrous carbohydrates corrected for ash and protein in kg/day and average daily gain increased linearly. Therefore, the use of supplementation at 0.5% BW (24% crude protein) to provide gains of up to 0.500 kg/day is recommended for grazing steers during the post-weaning period in the dry season of the year.

Ingestive behavior of grazing steers fed increasing levels of concentrate supplementation with different crude protein contents.

This study aimed to evaluate the ingestive behavior of steers on Brachiaria brizantha pasture fed diets with increasing levels of concentrate supplementation. Thirty-two crossbred steers in the finishing phase with average weight of 420 ± 8 kg were distributed in a completely randomized design with four treatments and eight replicates per treatment. Their behavior was assessed every 5 min for 24 h, in the middle of the experimental period. Variance and regression analyses at 0.05 % probability were adopted. The times spent grazing and ruminating reduced linearly (P <0.05), whereas the times spent at the trough (eating) and on other activities increased linearly (P <0.05) as the supplementation levels were elevated. The total feeding and chewing times decreased linearly (P <0.05) as the concentrate levels in the diet were elevated. By increasing the supplementation levels, the number of bites per day decreased linearly (P <0.05), and the feed efficiency of dry matter increased quadratically. Rumination efficiency of dry matter increased linearly (P <0.05) with increasing levels of concentrate supplementation. Grazing and rumination activities are reduced when the time devoted to other activities and at the trough are increased, as a result of the substitution effect.

Comparison of protein and energy supplementation to mineral supplementation on feeding behavior of grazing cattle during the rainy to the dry season transition.

The aim of this study was to evaluate the effects of protein-energy or mineral supplementation on the ingestive behavior of dairy steers on pasture in the post-weaning phase during the rainy to dry season transition. Twenty-two ½ Holstein-Zebu dairy steers with an average initial body weight of 234 ± 16 kg were distributed into a completely randomized design into two groups: protein-energy supplementation and mineral supplementation offered ad libitum. The steers receiving protein-energy supplementation showed higher (P < 0.05) intake of dry matter (DM) and neutral detergent fiber (NDF) than those fed diets composed of mineral salt only. In addition, the animals that received protein-energy supplementation had longer period in grazing and spent on average more time per period eating at the trough (P < 0.05), however no significant differences were observed in the time per period in rumination and time per period in idle (P > 0.05). The supply of protein-energy supplement does not change the feeding behavior, except for an increase in the time spent feeding at the trough. The intake of protein-energy supplement improved the of DM and NDF feed efficiencies in grazing cattle during the rainy to the dry season transition.