Female fertility is essential to any beef breeding program. However, little genetic gain has been made due long generation intervals and low levels of phenotyping. Days calving (DC) a trait that may provide lead an increased weaning rate. Genetic parameters correlations were estimated compared for DC across multiple joinings (first, second third+) lactation status (lactating non-lactating) trop...

Increased Milk Production, Concentration of Unsaturated Fatty Acids and Conjugated Linoleic Acid in the Holstein Lactating Cows using Monensin

BACKGROUND Fifteen lactating Holstein dairy cows were assigned to three diets in a 3 × 3 Latin square design to evaluate the effects of dietary forage sources on rumen microbiota, rumen fermentation and biogenic amines. Diets were isonitrogenous and isocaloric, with a forage/concentrate ratio of 45:55 (dry matter basis) but different main forage sources, namely cornstalk (CS), Leymus chinensis ...

The objective of this study was to determine the long-term effects of feeding monensin on methane (CH4) production in lactating dairy cows. Twenty-four lactating Holstein dairy cows (1.46 +/- 0.17 parity; 620 +/- 5.9 kg of live weight; 92.5 +/- 2.62 d in milk) housed in a tie-stall facility were used in the study. The study was conducted as paired comparisons in a completely randomized design w...

The US dairy sector is facing structural changes including a geographical shift in dairy production and a tendency toward the implementation of more intensive production systems. These changes might significantly affect farm efficiency, profitability, and the long-term economic sustainability of the dairy sector, especially in more traditional dairy production areas. Consequently, the goal of t...

bioavailability of three rumen protected methionine (met) sources with different protection methods (mepron® m85, evonik industries, germany; methioplus®, soda nutrition, italy and methilock®, tehrandaneh co. iran) were evaluated in 2 experiments with 6 canulated non-lactating holstein cows. in experiment 1, the ruminal in situ and mobile bag techniques were used for assessing ruminal degradabi...

1. The present paper reports the effects of dietary modifications on the diurnal pattern of concentrations of certain metabolites and hormones in the peripheral blood of lactating dairy cows. The cows were given fixed rations of hay and high-cereal concentrates in the proportions of 30:70 or 10:90 (w/w). The concentrates were given in either two or six equal meals daily; the hay was given twice...

The objectives of this study were to determine the effect of the dry cow management system (pasture or confined) on: (1) lying behaviour and activity; (2) feeding and heat stress behaviours; (3) intramammary infections, postpartum. Non-lactating Holstein cows were assigned to either deep-bedded, sand freestalls ( n = 14) or pasture ( n = 14) using rolling enrollment. At dry-off, cows were equip...

The automated, reliable, and early detection of lameness is an important aim for the future development of modern dairy operations. One promising indicator of lameness is a change in the feeding behavior of a cow. In this study, the associations between feeding behavior and lameness were evaluated. A herd of 50 cows was investigated during the winter season in a freestall barn. Feeding behavior...