Hematological profile of beef cattle with divergent residual feed intake, following feed deprivation

The objective of this work was to characterize the hematological profiles of steers and bulls, according to residual feed intake (RFI), after feed deprivation. Twenty‑month‑old Nellore steers and bulls were fed feedlot diets for 70 and 56 days, respectively. RFI was calculated as the difference between actual feed intake and expected feed intake. More and less efficient steers and bulls, according to RFI, were subjected to 24 hours of food deprivation. Blood was sampled prior to and following the withdrawal period. Hematological analyses included total and differential white blood cell count, red blood cell count and morphology, and plasma glucose concentration. Variation in RFI did not influence plasma glucose concentration or blood cell profiles. Glucose concentrations in bulls decreased from 114 to 97 mg dL‑1, but remained unchanged in steers, and the neutrophil:lymphocyte ratio increased from 0.39 to 0.57 following deprivation. Hematological profiles do not differ between more and less efficient steers and bulls, according to RFI.

Carbon and nitrogen cycling in an integrated soybean-beef cattle production system under different grazing intensities

Abstract:The objective of this work was to evaluate the effect of grazing intensity on the decomposition of cover crop pasture, dung, and soybean residues, as well as the C and N release rates from these residues in a long-term integrated soybean-beef cattle system under no-tillage. The experiment was initiated in 2001, with soybean cultivated in summer and black oat + Italian ryegrass in winter. The treatments consisted of four sward heights (10, 20, 30, and 40 cm), plus an ungrazed area, as the control. In 2009-2011, residues from pasture, dung, and soybean stems and leaves were placed in nylon-mesh litter bags and allowed to decompose for up to 258 days. With increasing grazing intensity, residual dry matter of the pasture decreased and that of dung increased. Pasture and dung lignin concentrations and C release rates were lower with moderate grazing intensity. C and N release rates from soybean residues are not affected by grazing intensity. The moderate grazing intensity produces higher quality residues, both for pasture and dung. Total C and N release is influenced by the greater residual dry matter produced when pastures were either lightly grazed or ungrazed.

Bulletin / Chambre du commerce d'exportation

1902/10 (N8).

Bulletin / Chambre du commerce d'exportation

1907/04 (N4).

Bulletin / Chambre du commerce d'exportation

1903/10 (N8).

Bulletin / Chambre du commerce d'exportation

1921/06 (N6).

Bulletin / Chambre du commerce d'exportation

1909/01 (N1).

Bulletin / Chambre du commerce d'exportation

1904/08 (N8).

Bulletin / Chambre du commerce d'exportation

1922/07 (N7)-1922/09.

Bulletin / Chambre du commerce d'exportation

1902/06 (N6).

Bulletin / Chambre du commerce d'exportation

1922/04 (N4).

Bulletin / Chambre du commerce d'exportation

1912/02 (N2).

Bulletin / Chambre du commerce d'exportation

1903/03 (N3).

Bulletin / Chambre du commerce d'exportation

1907/02 (N2).

Bulletin / Chambre du commerce d'exportation

1899/10 (N8).