 |
||||
|
||||
|
||||
A new study by Texas A&M University researchers indicates that neosporosis has a greater impact on beef production and feed efficiency than earlier studies indicated.
"This new information is extremely important and significant," Barling says. "For the first time, it clearly shows that neosporosis is a subclinical disease that substantially affects efficient beef production - quite possibly more than we thought just a year ago." Neosporosis is a parasitic disease that can trigger spontaneous abortions or abnormal births in beef and dairy cattle. It primarily affects the brain and nervous system of the developing calf which may result in an aborted fetus, a calf with abnormalities or an infected calf that has no obvious symptoms. Neospora caninum is transmitted, in part, by dogs that ingest infected tissues from aborted fetuses and set the parasite eggs, or Neospora ocysts, in their feces. The causative agent of the disease - a coccidian protozoan parasite known as Neospora caninum - is transmitted, in part, by dogs and was first identified in 1988. Barling's latest study, recently published in the Journal of the American Veterinary Medical Association (JAVMA), showed average daily gain (ADG) inNeospora-positive steers was .37 pounds lower than that in the seronegative test animals. This figure was substantially greater - more than three times - than the ADG results Barling saw in his first study and, according to Barling, better reflects Neospora caninum's impact on ADG. The lower ADG wasn't because the seropositive steers were eating less. When it came to feed intake, Neospora caninum did not significantly affect dry matter intake (DMI) - infected animals consumed only about .35 pounds less of feed each day than uninfected steers. However, the research determined that a Neospora-positive steer required 2.16 pounds of additional feed to increase live body weight by one pound. "In other words, Neospora didn't suppress appetite but it did suppress feed conversion," Barling says. "That's our most important finding in this latest research." Additional Texas A&M studies are underway in conjunction with Intervet. Intervet a researcher of Neospora caninum and developer of NeoGuard(TM), the only vaccine for bovine neosporosis. USDA recently granted full approval to NeoGuard(TM) and determined the vaccine "is efficacious as an aid in reducing abortions caused by Neospora caninum in pregnant cattle." As a fully licensed vaccine, NeoGuard(TM) - which has had limited availability on a conditional license since 1998 - will now be available to beef and dairy producers in all 50 states through veterinary clinics and animal health suppliers. The USDA approval culminates six years of research and development into bovine neosporosis and a Neospora caninum vaccine. NeoGuard is administered in the first trimester of pregnancy with a 5 mL subcutaneous injection followed by a second 5 mL dose three to four weeks later. Revaccination with two doses is recommended for subsequent pregnancies. |
||||
|
|
||||
|
||||
|
All information is copywrited by Feed Lot magazine and cannot be printed or re-printed
without the publishers express consent. Please contact
Feed Lot Magazine for reprint and copy authorization.
|
||||
