We all know that if you can get a cow or heifer through the three weeks pre-calving, calving and then the three weeks post-calving without incident, then it is very likely she will successfully complete the lactation. It is pretty safe to say that the transition is a very critical period in a dairy cow’s life. Let’s face it, you are basically trying to turn a couch potato into an Olympic-class athlete almost overnight.
When the system works, it really works. However, when the 60-day cull rate begins to spike, where is the first place we look to lay the blame? The nutritionist, right? Not quite. University of Wisconsin-Madison studies have shown that unless the diet is way off on protein, fiber and more, it does not even make the list. Fortunately, there are other factors that exert a greater influence and all can be controlled with good management.
1. Adequate Bunk Space — This is the most important factor affecting animal performance. It is likely this is why we tend to think it is a nutritional rather than facilities problem — either way the animals are not getting the diet they require.
Ideally, you want all animals in both the pre-fresh and post-fresh groups to be eating simultaneously to maximize the 90-minute period following fresh feed delivery and milking. If a more timid animal is excluded from eating at this time by more aggressive pen mates, they generally will not eat as much when, or if, they return later on.
Figure on a minimum of 30 inches of bunk space per cow. Bunk length must be calculated on this spacing per cow and not on the number of headlocks at the bunk. Standard headlocks are on 24-inch centers and this is fine for the remainder of the herd. However, for these two groups, the headlocks or vertical dividers must be 30 inches on center. Some sort of indexing barrier is preferable to a simple feed rail because when feeding at a rail, a boss cow will often stand at an angle to the bunk, thereby occupying two or three spaces. Headlocks or vertical bars encourages them to stand perpendicular to the bunk, thus freeing up the other one or two spaces.
To avoid overstocking and reducing bunk space during calving surges, multiply the average number of calvings for the period by 140% and calculate bunk length and pen size based on that number of animals. Yes, this may seem overbuilt, but how much production is lost and money expended to treat early lactation maladies such as retained placentas, metritis, ketosis and milk fever?
2. Appropriately Sized Stalls — Late gestation cows, especially large framed breeds like Holsteins and Brown Swiss, require extra space when negotiating freestalls. On average, cows are not getting smaller so the old freestall standard has been upgraded. This is just for the pre-fresh and post-fresh groups — the previous standard still works for the rest of the herd. However, a smaller freestall will accommodate smaller breeds like Jerseys.
Is it worth it? Ken Nordlund, faculty researcher at UW-M, relates the story of a herd he worked with on some transition cow issues. Prior to upgrading the stalls to the new dimensions there was a disparity in ME corrected milk between the first calf heifers and the mature cows. The first calf heifers did well, but the mature cows showed a 2,000-pound deficit. After retrofitting the stalls, the deficit disappeared.
If the groups are on bedded packs, or composted pack, figure on 100-120-square-feet per animal on the pack. Feed alleys are in addition to this number.
3. Soft Stall Surfaces — We know that deep bedded sand is the gold standard in the milking barn and it is no different here. Time budgets, hock lesions and locomotion scores are all improved on sand. However, when sand is not an option because of your manure handling system or other difficulty, deep bedded sawdust or chopped straw or hay works almost just as well. Unfortunately, according to UW-M studies, mattresses did not fare as well. In fact, they noted that animals housed on stalls with mattresses spent more time standing or perched in the stalls, less time eating, and produced as much as 8 pounds less milk per day. However, mattresses with more than 2 inches of bedding faired almost as well as deep bedded sand and may be a reasonable substitute where sand is not an option. Concrete, however, even with bedding or mattresses, is never an option for transition cows.
For bedded packs and composted packs, figure on a minimum of 3 inches of bedding — sand, sawdust or straw — over a compacted, well drained subgrade.