Bovine Top 20 Reproductive Diseases - Part 2 Flashcards
(49 cards)
what cows are most often affected by milk fever?
high producing dairy cows, cows on their 3rd or more lactation, jersey cows, & multiparous mature dairy or beef cows
when does milk fever occur in cows?
occurs within 72 hours post-parturition
what are the three stages of milk fever & their associated clinical signs?
stage I: ambulatory/weak/ataxia/down with normal head posture, hypersensitive/excitable/restless/aggressive, fine muscle tremors starting in flanks/triceps, & bellowing, stage II: sternal recumbency, obtunded, cool extremities/low temp, anorexic, increased heart rate & decreased heart sounds with weak pulses, neck in ‘s-curve’, & smooth muscle paralysis which can lead to bloat/failure to defecate/loss of anal sphincter tone/inability to urinate, & stage III: comatose, opisthonus, flaccid muscles, increased heart rate & no pulses
T/F: in milk fever cows, death can occur within hours if no intervention
TRUE
what are the three big things you must do when working up a cow for milk fever?
rule out sepsis in any down cow who calved recently, check the uterus for a possible dead twin, & check udder/quarters for milk for possible septic mastitis
whey does hyperglycemia occur in cows with milk fever?
low extracellular calcium inhibits insulin secretion
how is milk fever in a cow diagnosed?
history & physical (weak cow that recently calved or is about to), total blood calcium under 8.0 mg/dl, & ionized blood calcium under 4.5 mg/dl
what are signs that you need to stop giving calcium IV to a cow with milk fever?
calcium is cardiotoxic - stop & wait if bradycardia, arrhythmia, weakened pulse, or cow begins to pant
what signs are seen in a cow being treated for milk fever with calcium that indicates the treatment is working?
decreased heart rate, strong pulses, eructation, able to rise, & urination/defecation
why correct lateral recumbency in a cow down with milk fever?
prevent regurgitation & aspiration
how is milk fever in cows prevented?
low calcium diet during dry periods, dietary cation difference during late dry & early milking period to decrease blood pH, feed vitamin D3 late dry period, administer PTH right before parturition, & avoid diets high in potassium & low in anionic ions
T/F: 75% of cows with milk fever will stand up with treatment within 2 hours & 30% of those will relapse
TRUE
why is completely milking a cow out to decrease calcium reabsorption to prevent milk fever no longer recommended?
it leads to mastitis
what is the prognosis for a cow with milk fever?
good to excellent if no concurrent diseases
what is the normal stage 1 of parturition in cows?
uterine contractions & cervical dilation, completion is marked by amnion & part of fetus eneter the vagina ‘water breaking’, & usually lasts 1-4 hours
what is the normal stage 2 of parturition in cows?
beginning is marked with abdominal contractions, completion marked with fetal expulsion, usually lasts 1-4 hours, in mature cows, under 3 hours
what is the normal stage 3 of parturition in cows?
fetal membranes are expelled, beginning of uterine involution, & usually occurs 12 hours after parturition
what indicates dystocia in the different stages of parturition?
in stage 1 longer than 6 hours, in stage 2 amniotic sac is visible for 2 hours & cow isn’t trying, in stage 2 & cow is trying more than 30 minutes without progress, in stage 2 & cow not trying for over 20 minutes after initial progress
what indicates dystocia in heifers? what about cows?
heifers: deliver within 60-90 minutes of seeing calf’s feet, & cows: should deliver within 30-60 minutes of seeing calf’s feet
what are risk factors for dystocia in cows?
weight loss in late pregnancy, pelvic canal width, male calves, & cold weather leads to longer gestation & higher birth weight
what are some underlying causes of dystocia in cows?
fetopelvic disproportion (dam factors: genetics, age, parity, nutrition, & calf factors: size, genetics/environment, gender, gestational length, & genotype) malpresentation, over-conditioned dam, uterine torsion, milk fever, & uterine inertia
what is primary uterine inertia as a cause of dystocia? what about secondary uterine inertia?
primary: due to hypocalcemia, uterine overstretching, abnormal uterus, hormone levels, & contractions, secondary: exhaustion after prolonged attempts to expel fetus
how is dystocia prevented in cows?
if small pelvic canal width, either cull or breed to a small bull & watch calving closely, choose sires that have low weight calves by using expected progeny differences calculation for determining calf size
how is dystocia treated in cows?
vaginal assistance, traction, c-section (standing or under general anesthesia), or fetotomy if dead calf
