VOLUME 4, No 7 - NOVEMBER 97

Happy Thanksgiving!

Best wishes to everyone for a happy Thanksgiving holiday. The temps are getting colder and most parts of the state have seen the season's first snowfall. If you have weather-related questions or concerns, please feel free to contact us.

This month's issue of the Ranch Hand contains an article on a new law designed to prevent a BSE outbreak in the U.S. I encourage you to contact me if you have questions regarding the new law. The economic impact of a BSE outbreak (whether perceived or real) could be devastating for U.S. cattle producers.

Greg Lardy
NDSU Extension Beef Cattle Specialist

North Dakota Range Plant Book Released

Kevin Sedivec Rangeland Management Specialist

The NDSU Extension Service, along with the NDSU Ag Experiment Station and Animal and Range Sciences Department, have released

a range plant identification book for North Dakota and western Minnesota entitled, "Selected North Dakota and Minnesota Range Plants," by Kevin Sedivec and William Barker.

The book provides educational information about a selected group of range and pasture plants. A total of 123 plants were selected for this book. Each plant comprises 2 pages of the book and includes a color photo, distribution map, and line diagram; species and genus name, common names used in this region, and family name; a thorough plant description, followed by its origin, growing season, habitat, and distribution; a description of the plant's forage and wildlife value. Some plants have another category which may list medicinal value, use by Native Americans, and other pertinent information.

The book is designed for farmers and ranchers, professionals working with rangelands, college students, and high school youth. The North Dakota Range Judging Handbook lists 82 plants for contestants to identify, 64 are in the book.

To order, either call the NDSU Distribution Center at 701-231-7883 or send your check for $19.50 to NDSU Agriculture Communication - Distribution Center, Morrill Hall 7, Box 5655, Fargo, ND 58105-5655.

Bovine Spongiform Encephalopathy (BSE)

Greg Lardy Livestock Specialist

Bovine spongiform encephalopathy belongs to a group of diseases classified as transmissible spongiform encephalopathies (TSE's). The name is related to the fact that the brain in stricken animals becomes sponge-like in appearance. To date, the causative agent for BSE has not been identified. However, it is believed to be related to the presence of a prion, which is a small protein molecule. Ruminants seem to be especially sensitive to TSE's. Scrapie in sheep and chronic wasting disease in deer and elk are also TSE's.

TSE's are progressively degenerative diseases which affect the central nervous system. They generally have long incubation periods and a short clinical course of neurological signs. In all cases the death rate is 100%.

The first clinical cases of BSE were observed in England in 1986. Signs usually begin with apprehension, increased reaction to sound and touch, a swaying gait sometimes associated with high stepping, and kicking in the milking parlor. Other behavioral changes include changes in milking order, standing separate from the rest of the herd while on pasture, disorientation, staring at inanimate objects, and excessive licking of the nose or flanks. Final signs are falling, stumbling, inability to stand, coma, seizures, and death. Postmortem examination reveals few, if any, clinical lesions or signs of disease. Loss of body condition is generally noted. Histopathologically, the disease results in "bilateral symmetrical degenerative changes in the gray matter and neuronal vacuolation," which simply means the cattle get a spongy-looking brain.

To date, BSE has not been detected in the United States. Surveillance is ongoing to monitor the status of the U.S. beef and dairy herds. Scrapie, Transmissible Mink Encephalopathy, and Chronic Wasting Disease do occur in the U.S. In 1989, the U.S. banned imports of ruminant proteins from the United Kingdom. Cattle imports from the U.K. were also banned in 1989. APHIS (Animal and Plant Health Inspection Service; USDA) has attempted to locate and account for all cattle imported from the U.K. to the U.S. One case of BSE has been reported in Canada.

The U.K. has had 167,000 confirmed cases of BSE since December, 1986. Ninety-five percent of the cases have been in dairy cattle. The epidemic affected 60% of the herds in the U.K. The only common link in all the cases was that feeds containing meat and bone meal were fed to the affected animals. BSE has also been reported in France, Switzerland, The Netherlands, Portugal, Republic of Ireland, and Northern Ireland.

Humans can be affected by four TSE's, including Creutzfeldt-Jakob Disease, Gerstmann-Straussler-Scheinker Syndrome, Kuru, and Fatal Familial Insomnia. Creutzfeldt-Jakob Disease (CJD) is a sporadic disease of the central nervous system in humans. There are no known causes or risk factors. CJD occurs at an incidence level of about one case per million people. Symptoms initially manifest themselves as changes in sleeping and eating habits. Over the course of a few weeks, the patient's condition rapidly deteriorates and death occurs (in 90% of cases, death occurs within one year of diagnosis). Generally, CJD affects the older population. In the early 1990's, a new variant form of CJD, nvCJD, was identified in the U.K. This was identified as a new disease because of the neurological profile and the unusually young age of its victims (ages ranged from teens to thirties). Symptoms were similar, but included anxiety, nightmares, and depression. Twenty-one cases have been reported (20 in the U.K. and one in France). A review of patient histories revealed no apparent clues as to the cause of nvCJD. Scientists in the U.K. have stated that the most apparent explanation is exposure to the BSE agent. One other possible explanation given is the exposure to TSE agents from animals other than cattle.

It should be emphasized that these are basically theories at this time and no definite proof exists to link BSE to nvCJD. There is, however, enough evidence to warrant further examination into the cause and effect relationships. The U.S. government has taken action to limit the use of mammalian protein tissues in ruminant feeds. The details of this law are summarized in the following article.

Law Limits Use of Animal Tissue Protein in Feed for Ruminants

Greg Lardy

On August 4, 1997, Title 21, Code of Federal Regulations, Part 589.2000 took effect. Basically, the law, designed to help avoid possible problems with BSE, bans the use of animal tissues in feed for ruminants with the following exceptions:

Non-mammalian Tissues - marine (fish meal); poultry (feather meal, poultry byproduct meal, etc.); vegetable proteins (oilseed meals, etc.).

Non-Protein or Non-Tissue Feedstuffs - grease, tallow, amino acids, dicalcium phosphate, fat, oils.

Exempt Mammalian Protein - swine; equine; blood and blood products; milk and milk products; plate waste.

The regulations establish requirements for compliance which apply to renderers, protein blenders, feed manufacturers, distributors, and individuals or firms which are responsible for feeding ruminant animals. For firms which render animals or produce feed, the law stipulates compliance procedures for mill clean-out which must be followed when using feeds or protein sources of animal origin. In addition, labeling requirements must be met to sell feeds or products which contain feeds of animal origin.

Farmers and ranchers who feed ruminants are required to do the following:

• Maintain copies of all invoices for ALL feeds received that contain animal protein. Maintain copies of labeling for ALL feeds containing animal protein byproducts. Make copies of invoices and labeling available for FDA inspection and copying. Maintain records for a minimum of one year.
• Renderers, feed manufacturers, protein blenders, distributors, and farmers/ranchers are subject to spot checks by FDA or the state Department of Agriculture to monitor compliance.

Feed Quality of Slough Hay

Kevin Sedivec

Seasonal wetlands cover approximately 3 million acres of North Dakota, providing habitat for many wildlife species. These wetlands have also become a significant source for harvested forages used for feeding livestock. Livestock readily graze many plant species associated with wetlands, especially early and late in the growing season. The question commonly asked is what is the feed value, both in terms of palatability and quality, of wetland vegetation (slough hay) put up for hay. To best answer this question, the producer must know the plant species composition of the slough hay. Timing (stage of plant development) of hay harvest must also be accounted for when providing a higher quality feed.

Palatability is a major concern when determining the overall use and importance of wetland vegetation. Even if the quality is high, if livestock limit intake due to low palatability (taste), the importance as feed will be limited unless implementing a grinding process with a total mixed ration. Wetland plant species will vary dramatically in palatability. Palatability will also differ for some plant species due to timing of harvest. Table 1 shows which plants are palatable, which are palatable early (prior to heading) but not palatable once mature, and those that are unpalatable or low in palatability.