There has been much discussion recently on the competitiveness of dairying in the Midwest. Attention is usually focused on producing milk at the lowest possible cost. Profit-conscious dairy managers should know what it costs to produce a hundred pounds of milk. Usually it is feed, labors and capital investment related costs that concern producers the most. This is logical as these make up from 70 to 80 percent of the cost of producing milk. However, energy costs, although a smaller expense than these, also deserves close attention as the dairy producer attempts to produce milk at the least cost possible and widen the profit margin.

Energy audits conducted on dairy farms show considerable variation in energy use. Liquid fuel (usually measured in terms of gallons of gasoline) will average 40 gallons per animal unit annually. Nearly 75% of this is used in forage and grain production and the balance in manure disposal and miscellaneous tractor use and farm truck travel. The manure disposal use can increase where it is necessary to have some distance to spread manure. Injecting or incorporating manure will raise the energy requirement some 15 to 20 percent. However, incorporating the manure into the soil reduces nutrient loss and consequently the need to purchase commercial fertilizer.

Because of environmental concerns - odor control and pollution potential - the entire area of waste disposal need to be considered and will most certainly take on added significance in the near future. Waste handling systems will be planned based on the nutrient load in the soil. This could increase fuel requirements in some instances. It may well be necessary to travel greater distances to balance the nutrient load as opposed to spreading on the nearest available field.

Soil tests reported by some dairy and swine producers have indicated some high phosphorus readings on some fields. This may become more prevalent as more operators move toward some type of rapid incorporation. Nitrogen build up has seldom been a concern because nitrogen losses in most conventional systems are quite high and normal cropping procedure utilizes enough to prevent excesses. Again, changes in methods may alter this picture.

Table 1 shows the averaage manure production and nutrient content. More precise numbers can be obtained for any individual farm by having manure samples analyzed. The volume will also vary depending upon the amount of bedding or if it is a solid or liquid system. These values are the numbers needed when considering such questions as: 1) what is manure worth? 2) what is the volume to be stored or spread? 3) what is the possiblity of nutrient building?

Figure 1. Percent of the BTU energy used in dairy farming (Source: USDA).

Energy use associated with the dairy operation (excluding feed production) are shown in Chart 2. Larger herds will use a greater percentage of energy cooling milk and a lower percentage heating water. The reverse is true on smaller farms. Some kind of heat transfer and/or heat recovery units are becoming standard equipment on dairy farms. Energy savings are sufficient to show a 3-4 year payback period.

A trend in recent years has been to have more open housing for the dairy herd. Many recently built structures have open ridges, open eaves, and curtain sides to provide more natural ventilation. These structures reduce ventilation costs and the amount of air provides a drier environment that is more conducive to animal foot health and cleanliness.

Cleanliness is important to both cow comfort and performance. Workers at Wisconsin's Marshfield Station assigned ratings for mud, snow, or manure to replacement heifers on a trial looking at cold stress. Heifers with no mud on their bodies were scored as none. Those with mud on their legs and abdomen were scored as medium. Heifers that had mud on their legs, abdomen, sides or flanks or both were scored as heavy. Heifers with no mud gained 1.83 pounds per day as compared to 1.79 for those considered medium. Heifers with heavy body mud and/or manure scores had an average daily gain of 1.65 pounds, a reduction of 10%.

Similar studies on producing cows are not well documented. However it would seem that they could be affected in a similar manner. Wet and/or muddy conditions would no doubt increase cold stress and impair performance. This line of thought would say that keeping cows dry and clean could result in a 10% increase in production.

Keeping floors as dry and clean as possible not only makes it more comfortable for cows, it reduces the chance of foot lesions. English workers found a direct relationship between the number of hours per day that cows stood in wet conditions and the percentage of cows with lesions of various kinds.

Surfaces should allow for animals to move freely, sure footed, without the fear of slipping. Surfaces that are too smooth cause cows to slip and can cause injury. These kinds of surfaces impair cows willingness and/or ability to mount, thus making heat detection difficult.

Finishes that are too rough may cause excess wear on the hoof wall. This puts aditional pressure on the sole of the foot and can cause bruises and/or lesions leading to lameness.

Bedding is another consideration in keeping cows confortable and healthy. Many products are being used successfully by dairy managers in the midwest. The amount of bedding is probably more important than the kind. If there is insufficient amount or if stalls are not regularly cleaned and maintained, the results will likely be unsatisfactory no matter what material is used.