red
Well-known member
This was in the Farm Journal's Beef issue. I found it to be very informative.
For the entire article go to:
http://www.agweb.com/get_article.aspx?src=&pageid=135184
What bovine viral diarrhea (BVD) looks like
Recognizing the presence of bovine viral diarrhea (BVD) virus in a cowherd can be likened to growing older—you may see subtle signs without realizing what has actually happened. Just as wrinkles and stiff knees may indicate the other side of the hill is closer, a number of seemingly isolated problems may suggest BVD is circulating in your herd.
For example, newborn calves that fail to nurse or have difficulty standing or walking can be associated with certain birth defects caused by BVD. Sporadic abortions or even decreased pregnancy rates may be signs of the disease, as well as bouts with respiratory disease or calf scours. On the weird side, BVD can cause a bleeding syndrome where cattle can bleed to death either spontaneously or after a routine procedure like an injection or castration.
Susceptible cattle can get an acute BVD infection any time during life. Most acute infections do not result in detectably sick cattle. Fetal infections frequently occur when pregnant females are acutely infected. The type of damage to the fetus varies, mostly dependent on the stage of gestation at which the infection occurred. Acute BVD is transmitted from animal to animal by inhalation or ingestion of saliva, bodily discharge or feces. In acute cases, you might see the obvious signs—fever, diarrhea, anorexia, ulcers, depression, excess salivation or respiratory problems.
There is also a peracute version of BVD. The animals have basically the same symptoms, but may die quickly. Peracute BVD is related to a specific strain that causes especially severe symptoms.
Chronic BVD infections are also similar, though there may be hair loss, lameness and more death than with acute cases. The animals may be more obvious—the classic poor-doers.
Another outcome of BVD infection is the persistently infected animal. This occurs when the fetus is infected at about 1½ to 4 months gestation. An animal cannot become persistently infected unless born that way. Many PI calves die early early in life from the effects of the infection or from secondary infection like pneumonia.
It’s estimated that half of all PI calves die before weaning and another half will die between weaning and slaughter. While some may be obviously unthrifty, others will appear perfectly normal.
At the extreme end of the scale, BVD can develop into a fatal form—mucosal disease—but only if the animal is a PI. Again, the symptoms are similar, though more severe, and erosions in the digestive tract, including the mouth, may be bad.
However, not all PI animals develop mucosal disease. Chronic BVD infections are a form of mucosal disease. The animals may also be more obvious from a physical standpoint—they are often found in groups of classic poor-doers
I'm sure that DL can add a lot to this but there were signs that I didn't know to look for in cattle.
Red
For the entire article go to:
http://www.agweb.com/get_article.aspx?src=&pageid=135184
What bovine viral diarrhea (BVD) looks like
Recognizing the presence of bovine viral diarrhea (BVD) virus in a cowherd can be likened to growing older—you may see subtle signs without realizing what has actually happened. Just as wrinkles and stiff knees may indicate the other side of the hill is closer, a number of seemingly isolated problems may suggest BVD is circulating in your herd.
For example, newborn calves that fail to nurse or have difficulty standing or walking can be associated with certain birth defects caused by BVD. Sporadic abortions or even decreased pregnancy rates may be signs of the disease, as well as bouts with respiratory disease or calf scours. On the weird side, BVD can cause a bleeding syndrome where cattle can bleed to death either spontaneously or after a routine procedure like an injection or castration.
Susceptible cattle can get an acute BVD infection any time during life. Most acute infections do not result in detectably sick cattle. Fetal infections frequently occur when pregnant females are acutely infected. The type of damage to the fetus varies, mostly dependent on the stage of gestation at which the infection occurred. Acute BVD is transmitted from animal to animal by inhalation or ingestion of saliva, bodily discharge or feces. In acute cases, you might see the obvious signs—fever, diarrhea, anorexia, ulcers, depression, excess salivation or respiratory problems.
There is also a peracute version of BVD. The animals have basically the same symptoms, but may die quickly. Peracute BVD is related to a specific strain that causes especially severe symptoms.
Chronic BVD infections are also similar, though there may be hair loss, lameness and more death than with acute cases. The animals may be more obvious—the classic poor-doers.
Another outcome of BVD infection is the persistently infected animal. This occurs when the fetus is infected at about 1½ to 4 months gestation. An animal cannot become persistently infected unless born that way. Many PI calves die early early in life from the effects of the infection or from secondary infection like pneumonia.
It’s estimated that half of all PI calves die before weaning and another half will die between weaning and slaughter. While some may be obviously unthrifty, others will appear perfectly normal.
At the extreme end of the scale, BVD can develop into a fatal form—mucosal disease—but only if the animal is a PI. Again, the symptoms are similar, though more severe, and erosions in the digestive tract, including the mouth, may be bad.
However, not all PI animals develop mucosal disease. Chronic BVD infections are a form of mucosal disease. The animals may also be more obvious from a physical standpoint—they are often found in groups of classic poor-doers
I'm sure that DL can add a lot to this but there were signs that I didn't know to look for in cattle.
Red