In This Issue

Neospora

Neosporosis continues to be a major cause of abortions in California dairies and in other parts of the world. The definitive host of Neospora caninum, the protozoan responsible, was unknown until recently. Dr. Milt McAllister, University of Illinois, has shown that dogs are a definitive host and cats or rats are not. Coyotes are suspect and more research may indicate other animals are involved. Dr. McAllister stated in the recent South Valley Dairy Day that wild canids should be tested along with dogs, especially where abortion storms have occurred.

Dr. McAllister stressed that producers take measures to prevent dogs and coyotes from defecating in stored feeds. This includes those in commodity barns, plus hay and silage and other feeds on slabs.

Once the dog fecal material is mixed in a TMR it could potentially infect several cows. Preventing this feed contamination is easier said than done. Possibilities include fencing, additional coverings, and training owner's pets to stay away from feed areas. Also stressed was to dispose of as many aborted fetuses before canids could get to them, and to control the number of canids on the farm.

Currently there is no therapeutic treatment for N. Caninum infected cattle. Abortions affect fetal brain and other tissues that are used for diagnostic verification. Serology lab tests can also lead to a presumptive diagnosis. A new vaccine will be introduced for neosporosis in February. This will be followed by efficacy studies on dairies. Obviously this is a complex problem that must be controlled by more than any one route. Reduction of the problem by prevention clearly will help.

DOPP

The Dairy Options Pilot Program, DOPP, is scheduled for March 16th in the Visalia Ag Building at the corner of West Main and Woodland. This is where the Ag Commissioner and University of California Cooperative Extension offices are located. This training session is from 10 to 2 with a no-host lunch break. For more information call the Farm Advisor's office, 733-6488. This meeting is required if you wish to use this USDA program, and it is suggested to call ahead to reserve a seat.

TC Dairies

As of January 1999 Tulare County now has 312,340 cows (milking and dry) on a total 291 dairies. This raises the herd size average to 1073 cows per herd. One year ago the figures were 305,390 cows on 293 farms, for an average size of 1,040. This continues the trend that has been seen over the years toward larger herds, as farm numbers hold fairly constant and total cow numbers grow. The graphs on the following page illustrate this with a 5-year comparison between 1994 and 1999.

Number of farms with less than 200 cows remains relatively unchanged and represents 5% of the total dairies. A noticeable drop has occurred in the numbers of herds with 200 to 600 cows, while herds with 600 to 1000 cows increased slightly during the 5-year span. Herds with 1000 to 1500 cows grew from 56% in 1994 to 59% now. The other noticeable growth has been in the 1500 to over 2500 cow herds during this same time frame, and indications are this trend will continue.

Meetings

• Western Dairyman's Seminars, Tulare Farm Equipment Show, Feb. 9-11, at 11 and 12 a.m.
• Southwest Nutrition Conference, Phoenix, AZ (Call farm advisor for details.)
• UC Davis Dairy Day, UC Davis main campus, March 24th (details in next month's Milklines)