With the high cost of pasture and rangeland, alternatives to grassland cow-calf production are being investigated with cows and/or calves being in confinement all or part of the production cycle. There are many management options with year-round confinement in regions where grazing grass or crop residue is not possible or desirable, short-season grassland grazing during summer and confinement during winter, or confinement during summer and crop residue/cover crop grazing during winter. Harvesting and delivering feed to the cow rather than the cow harvesting feed herself always adds cost to the production system, and thus, confinement or semi-confinement cow-calf systems have additional costs that need to be offset in some way.
One advantage of having cows in confinement is improved feed management with control over the quality and quantity of feed consumed by the cow-calf pair. By limit feeding cows a high energy, by-product diet during the confinement period, maintenance energy requirement is reduced 20 to 40% compared with a low-energy, forage diet fed ad libitum. This reduction in maintenance energy requirement decreases the total feed energy necessary to maintain the cow. Additionally, the calf has access to higher quality feed (ration vs. grass) and weaning weight is increased if the confinement period coincides with mid and late lactation. The higher quality and lower quantity of feed consumed by the cow reduced methane emissions and would likely require less land improving the sustainability of beef production.
But, as mentioned above, there are additional costs for feed, facilities and equipment, and labor; studies indicate that the net returns decrease as the length of the confinement period increases. Additionally, even though less total land would be used, the amount of land under intensive crop production would likely increase reducing ecosystem services provided by grasslands. Also, the conversion efficiency of non-human edible protein to human edible protein decreases with the use of high-energy, by-product diets because more human edible protein is used in the diet. Protein conversion efficiency is one of the most positive attributes of using ruminants for food production and should be a primary goal in designing any cattle production system.
Developing an economically and environmentally sustainable cow-calf production system will be difficult. Changing one aspect of the system to cause an improvement in one metric can easily result in moving another metric in the wrong direction. The beef cattle production system needs to be evaluated as a whole and careful analysis should be completed before making decisions.
Figure 1. Cow maintenance energy requirement (MEm, Mcal/kg.75), cow methane emissions (CH4, CO2 equivalents/kg HeP), human edible protein conversion efficiency (HePCE, %), and net returns (Returns, $/cow) for conventional pasture-based and semi-confinement (3-4 months) cow-calf production systems