Nutritional Management of Lactating Dairy Cows

Abstract

Nutritional management of lactating dairy cows varies with type of production system, but an effective feeding system allows cows to achieve maximum intake of a properly balanced ration to optimize production, health, and reproduction. Specifi c feeding strategies are used by the different production systems, and diet formulation and feed delivery will be completely different for cows subjected to a grazing system compared with herds in total confi nement. As production per cow continues to increase with genetic selection and improvements in management, the need to provide the correct amount of nutrients and certain dietary compounds such as forage and fi ber become more critical, particularly during late gestation and early lactation. Dairy cows in early lactation undergo a period of negative nutrient balance, which can be exacerbated by diseases or external factors that impair feed intake. Formulating diets that maximize nutrient intake in the fi rst weeks postpartum not only improves yields of milk and milk components, but also minimizes losses of body reserves and reduces the risk of postparturient health problems. This is critical because a large component of the success of a nutritional program of a dairy herd relies on feeding cows to minimize health problems. Similarly, as production declines with advancing lactation, so do the nutrient needs of the cow; therefore, tailoring the diet according to feed intake, level of production, and stage of lactation becomes critical to optimize nutrient utilization, reduce feed costs, and minimize the impact of production on the environment.Dairy Production Medicine, First Edition. Edited by Carlos A. Risco, Pedro Melendez Retamal.

Haematological, biochemical and endocrinological profiles in crossbred postpartum anestrus cows under tropical island ecosystem

“…The ovarian inactivity and anoestrus risk are associated with reduced concentration of blood E2 and antioxidant enzymes such as SOD, GSHPx and CAT (El-Bayomi et al 2018). Reduced concentrations of E2 are sufficient to block the pulsatility of GnRH and LH, thus impeding the follicle growth leading to non-cyclicity in PPA cows (Santos 2011). Animals with acyclic smooth inactive ovaries revealed a significant reduction in serum P4 than in cyclic animals (Ahmad et al 2004).…”

Two Possibile Hormonal Treatment Methods for Inducing Follicular Growth in Dairy Cows With Inactive-Static Ovaries

“…This could lead to assumption that smaller doses of GnRH and eCG may have partially effect of the initiation of the follicular growth in cows with inactive ovaries. However, it should be noted that, in the early postpartum period, most of the cows are unable to meet their energy requirements as a result of decreased feed intake at a time when energy requirements are increasing (31). Therefore, an early pospartum cows enter a period of negative energy balance (NEB) which usually demises after 60 days postpartum (8).…”

Effect of Dry Heat Temperature and Moist Heat Pressure on Canola Meal for Ruminant Utilisation. Part I: Nutritional, Protein Solubility and Degradability Characteristics

“…Canola (rapeseed, Brassica spp. napus, rapa, and juncea) meal is a derivative of seed oil production utilised as a protein supplement in dairy cattle feed (Sánchez & Claypool, 1983), due to its desirable AA profile and digestibility (Santos, 2011). Current literature reports RUP in canola meal ranges from 10.1 to 75.0% CP (NRC, 2001;Purser & Woodroofe, 2004).…”