DHI Notes...

November 2006 | Focus on health and comfort of your cows | Bennet Cassell

State DHI averages for important management areas in October 2006

Management area	October 2006	Change from last year
Rolling herd average milk	21683	+472 lbs.
Peak yield in heifers	76	1 lbs.
Days to first breeding	95	0 days
Days open	166	+5 days
Net Merit of proven service sires	$292	*
Herd turnover less dairy sales (%)	29%	-1%
Monthly average SCS	3.4	0.0
Feed cost per cwt. (milking cows)	$5.64	$0.01
Milk blend price	$13.61	-$2.25

*Net Merit changed in August 2006 and averages are not comparable.

here is one consistent trend in recent months in the table of management areas. Many of you are well aware of it already as you keep track of the bulk tank readings which show the trend much quicker. Rolling herd average milk for the state is dropping. It peaked in July at 21,838 lbs, but the writing was on the wall. That month, the test period average milk for the test period added to the average was 55.8 lbs, but the month dropped (from July of 2004) was 57.1 lbs per cow. The problem continues today – the average from 2005 that was dropped this month was 0.9 lbs higher than the one that was added. The difference is not as great as it was but the trend continues. Those figures of month added and month dropped, by the way, appear at the bottom of the “Yearly production and mastitis summary” section of the Herd Summary DHI-202. Like the DHI rolling herd average itself, average monthly yields are for all cows in the herd, milking or dry. The average reflects production and reproductive performance. As days open lengthen, more cows are milking in late (maybe very late) lactation. At the same time, more cows may actually be in milk than when calving intervals are shorter. It’s a dynamic and complex process. But the strongest factor in moving rolling herd averages up or down in this state is the quality of forages available in the feed bunk. The Virginia dairy industry feeds homegrown forages, and forage quality varies from year to year. In other parts of the US, forage quality is much more consistent. For instance, silage harvested from center pivots in the Panhandle of Texas or irrigated alfalfa along the Rio Grande will be of higher quality and much more consistent than Virginia forages almost every year. The harsh reality is that Virginia dairy producers must compete with milk produced under those conditions. Also, herds with access to high quality forage don’t have to decide how much supplemental feed to NOT buy when milk prices are low. What to do? Supplement variable quality forages as long as the increase in value of milk produced recovers the cost of the supplement plus an ample margin for risk and trouble. Focus on the health and comfort of the cows. Virginia might not have irrigated alfalfa, but producers in this state can take good care of cows.

Bennet Cassell
Genetics and Management