Feeding of lactating ewes.

Abstract

Milk production with dairy ewes requires more intensive systems and more nutrients per animal than are usually necessary for meat or wool production systems. During lactation, nutrient requirements may be very high. Inadequate feeding may reduce both the daily milk production and the length of the lactation. Adequate feeding requires proper balancing of rations. This, in turn, requires estimation of the nutrient requirements and feed intake of the animals and of the nutritive value of the feed. Proper feeding strategies for the lactating ewe cannot be based simply on what is known about dairy cows. Even though much of the information available for dairy cattle is valid for dairy sheep, it is necessary to be aware of the differences between the two species to avoid using inappropriate feeding strategies for the lactating ewe.

Effects of short-term feed restriction on milk yield and composition, and hormone and metabolite profiles in mid-lactation Sarda dairy sheep with different body condition score

“…The decrease in milk production at the last day of FR (Day 3) was of 38 and 35% of the milk yield of the Prel period in H-BCS and L-BCS ewes, respectively. The observed reduction in milk yield associated with FR was expected given the design of the experiment: the energy balance, calculated as the difference between energy intake and energy requirement (for milk fat and protein yields and maintenance) as a function of live weight (Cannas, 2004;NRC, 2007) was negative (mean -1.35 Mcal/d) in the FR period for both BCS groups.…”

“…Temporary undernutrition can also be a result of inappropriate management practices (e.g. regrouping of animals) which can lead to competition among sheep, incorrect evaluation of feed intake or inadequate nutritive value of the ration (Cannas, 2004).…”

Models for estimating feed intake in small ruminants

“…Indeed, compared with cattle, sheep and goats (Cannas, 2004): i) have to eat more (higher level of intake) to satisfy their maintenance requirements, which results in a higher passage rate of feed and lower fiber (forage) digestibility; ii) tend to have more selective feeding behavior; iii) have their intake more affected by the particle size and the fiber content of the forage and can ruminate feed particles of smaller size; iv) have to spend more time eating and ruminating each kilogram of feed; and v) tend to have higher digestibility of grains and highenergy diets.…”

“…Unfortunately, very few data are available to define the optimal dietary fiber concentration and dietary particle size of sheep and goats (Cannas, 2004). Indeed, these dietary factors can have a large impact on the DMI of small ruminants and are usually considered by prediction equations of DMI for cattle.…”

“…The comparison included animals of different BW, milk yield and BW gain. The CP concentration was estimated by using the optimal values reported by Cannas (2004) for animals varying in milk yield and BW. In one scenario, DMI was also calculated by considering a CP excess, i.e., 19.1% of dietary CP content instead of the 16.6% suggested by Cannas (2004).…”