Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
18 Cards in this Set
- Front
- Back
|
% BLV positive animals that become critical
|
-.5-5%
|
|
|
BLV
-clinical signs |
-lymphadenopathy (abdominal & subcutaneous)
-exophthalmos (eye bulge) -diffusely thickened uterus -melena -CHF --> brisket and ventral edema |
|
|
Lymphadenopathy
-presentation |
-off feed
-low production -discover intra-abdominal lymphadenopathy via trans-rectal palpation |
|
|
BLV
-transmission |
Vertical
-in utero Horizontal -insects (minor) - blood carrying mosquitos & flies that are found in warmer areas in the summer and fall -Iatrogenic (multiple use needles, multiple use palpation sleeves, ultrasound probe, contaminated vaccines, dehorning instruments) -Milk -Colostrum |
|
|
BLV
-effects |
-milk production (mixed conclusion on effect)
-reproduction ( -economic-productive life (mixed association b/n BLV +/- cows and length of productive life) |
|
|
BLV
-control |
-test & cull all positives (purchase only neg. animals as replacements)
or -test and isolate positives + management practices (single use needles, single glove use, ultrasound probe disinfection, pasteurized milk, fly control) or -Management practices (single use needles, single glove use, ultrasound probe disinfection, pasteurized milk, fly control) |
|
|
BLV control
-issues with test and cull |
-what if the prevalence is high
-what does it cost to raise/purchase and test a replacement |
|
|
BLV control
-issues with test, segregate, and use management practices |
-how often will tests need to be done to find new positives
-do cows ever get put into the wrong pen |
|
|
BLV control
-issues with management practices |
-cost of needles and sleeves (shouldn't be significant)
-cost of added labor -possibly need people to change routines -difficult to affect management-practice changes concerned with diseases whose effects are not measured or observed |
|
|
BLV control
-what compnents are easier to discuss with management |
Disease entities that can be observed
-high death rate -clinical mastitis rates -elevated bulk tank SCC -poor reproductive performance |
|
|
Link between BLV and human health
|
-currently no link recognized
-BLV milk at grocery stores probably won't go over well though |
|
|
BVDV
-evidence it may circling in a herd |
-inc. early embryonic death rates
-sudden late term abortion storm -several adult milk-cow pneumonias or common fresh-cow disorders (non-responsive to treatment) |
|
|
First step to diagnosing a health problem
|
-decide if the apparent problem is real
|
|
|
BVDV
-if you have confirmed that a disease process is occuring, what can be presumed? |
-there is a PI animal somewhere in the herd
|
|
|
BVDV
-how to screen populations most likely to contain the PI |
-conduct pen/barn-wise bulktank BVDV test
-if a positive shows, test all animals within that population (make sire no animal is moved from the pen/barn between milk and tissue sampling) |
|
|
BVDV
-if a PI animal is somewhere in the herd but cannot be pinopinted, what should you do? |
-conduct a whole herd bulk-tank sample
|
|
|
Down-side of completing a testing program looking for BVDV?
|
-PI might not be in the herd any longer (succumb to other illnesses)
-investigation reveals no PI -No PI found (makes it difficult to convince the producer the testing is still needed) |
|
|
BVDV control
-closed herd -open/expansion herd |
Closed herd
-not really a thing -active vaccination program designed by the DVM Open herd -test all incoming animals for BVDV before entry -isolate the animals away from all breeding age animals for 30-45 days -test all newborn calves for PI status -complete bulk tank BVDV tests for surveillance -do these things FOREVER |
