The public has been critical about the handling of non-ambulatory cows (disabled cows; "downer" cows) during the last five years in California. Senate Bill 692, introduced in 1993 and passed in 1995, eliminated the unloading of "downer" cows at auction yards, but allowed USDA-inspected packing plants to accept these cows for slaughter. A pilot study was designed to examine the critical health and welfare factors of these disabled cows presented at USDA-inspected packing plants.

The study was conducted at two commercial slaughter facilities near San Bernardino County's Dairy Preserve in southern California. This location was selected due to the high concentration of dairies in a relatively small area which enabled researchers to obtain history and records of the cow from the dairy producer within a few days of slaughter. The data was collected during the summer months. Fifty mature dairy cows served as subjects. One criterion of an ante-mortem exam is a rectal temperature below 104 degrees F. All animals received a complete physical examination.

Fecal samples were collected on each cow for the determination of the presence of the Salmonellae species; while 20 rumen samples were collected and submitted for the identification of E. coli 0157:H7. Blood cultures were performed to detect the presence of bacteremia. Serum from venous blood samples was harvested and frozen until immunoassays were performed for concentration of cortisol (Munro and Stabenfeldt, 1985) and the acute phase protein, alpha-acid glycoprotein (AGP) (Development Technologies International, Inc., St. Frederick, MD). Data also documented the handling methods used to unload each animal upon delivery to the facility, the estimated distance traveled between the dairy and the processing facility, and the type of vehicle used for transportation.

Table 1 indicates the distance cows were transported between the dairy and the processing facility. Ninety percent of the cows were located on dairies less than 10 miles from the processing facility; thus, transportation stress under commercial conditions due to distance was minimal. The transport vehicles included flatbed trucks (45), semitrailers (2), goose neck trailers (1), and no data was recorded for two animals. The unloading mechanism of the cows consisted primarily of a specially designed sled (39) which slid the recumbent animal from the bed of the truck to the ground, while chains wrapped around the limbs were used in 10 of the cows; no data was recorded for one animal. The age of the cow was determined by physical examination and/or history documented at the dairy (Table 2). The majority of downed cows were four years of age or older.

The primary diagnosis of the number of cows in each category along with the number of cows in that category which were condemned in the packing plant are shown in Table 3. The largest category was injury which included fractures, splitters, bruising, etc.; often confirmed by history documented at the dairy. The medical conditions of twelve cows were determined to be associated with calving paralysis and three of these carcasses were condemned. Fifty percent of the mastitis-related diagnoses were condemned; while 80 percent of the five cases of lymphosarcoma were condemned. Two cows were diagnosed with metritis; whereas the five cows in the "other" category included diagnoses of pneumonia, gastroenteritis, left displaced abomasum and septicemia.

All rumen samples were collected from 20 cows and submitted for identification of E. coli 0157:H7 were negative. Six cows were identified as Salmonella fecal shedders, while one cow was speticemic (Salmonella dublin and Pasteurella multocida).

Stress is often utilized as an indicator of the welfare status of an animal; thus, cortisol and AGP were quantified. The mean concentration for cortisol in the "downer" cows was 24+17 ng/ml which is approximately three times the upper "normal" limit of 8 ug/ml (Wilkinson, 1980). The mean AGP level of 874+577 ug/mg was quantified in the "downer" cows, which is approximately twice the upper "normal" limit of 450 ug/ml established for cattle (Saikin Kagaku Institute, Sendai, Japan). This data suggests that these cows had experienced severe stress, probably due to their non-ambulatory condition.

Larger numbers of cows at different regions of California or possibly throughout the U.S. need to be examined before broad-based conclusions and recommendations can be developed. The season of the year, transportation distance, and specialized transportation vehicles may influence the data and should be addressed. However, prevention of injuries and improved dry cow nutrition programs at the dairy may significantly decrease the number of non-ambulatory cows presented at slaughter. Options existing for non-ambulatory mature cattle may include the following suggestions:

* "Special processing facility" with special transportation modes;

* Home consumption with the warning of possible food safety concerns; or

* Humanely euthanize animals "on farm."

Tables 1, 2 and 3

References

Munro, C. and G. Stabenfeldt. 1985. Development of a cortisol enzyme immunoassay in plasma. Clincial Chemistry. 31 (6):956.

Wilkinson, J.S. 1980. Pituitary and adrenal function. In: Clinical Biochemistry of Domestic Animals, 3rd ed., J.J. Kaneko (editor), Academic Press, New York, N.Y., pp. 468-469.