Sheep - Dz's and conditions of Sheep Flashcards
Explain the sheep production cycle starting in October
Oct - flush ewes to inc plane of nutrition prior to breeding. Improve ovulation, conception and embryo implantation
Nov - Ram turnout (2 cycles, 1 cycle 17d)
Dec - Pull rams (scan for preg % fetal # 80d later)
Feb-Mar: vx ewe, inc nutrition
April - Lambing (gest 144-151)
May - vx lambs, castrate/tail dog <7 days, max 6wks for elastrators, burdizzo
June - vx booster
July-sept: marketing lambs
What is the ideal age for castration and tail docking? What is the maximum age for elastrators, and burdizzos
<7 days ideal
6 weeks max
What are 3 reasons for a lamb to lose their suckle reflex?
- hypoglycemia
- hypothermia
- dehydration
Explain hypothermia in terms of lost suckle reflex in lambs
prolonged delivery, immature (sm) lamb, vry cold weather
onset within 5 hrs of birth, not usually hypoglycemic
failure to ingest colostrum - low heat prod, onset 12 hrs + from birth, also hypoglycemic
What are the signs and treatment of a lamh with hypothermia?
rectal temp <39C, dull, weak, failure to suckle, separation from ew/flock, recumbency, death
MILD: 37-39, tube fed colostrum (must be able to swallow), make sure lamb + ewe are mothered up in a draft free environment
SEVERE: <37, <5hrs, warm first to 37 then tube feed colostrum. >5hrs, feed by tube if still swallows, give abdominal (IP) dextrose if cannot swallow, move to warming box, give colostrum by tube when recovered (swallow returns)
What is a warming box?
A heater with a fan - warms air to 37-40
check lamb temps every 30 min
remove lamb when temp >37
immersion in 38C (for 28mins)
Describe how to tube a lamb
sit with lamb on lap
use rubber urinary catheter and lubricate it
insert into interdental space and gently advance
check placement as for calves
give colostrum at 50ml/kg body weight
What do you need for a intraperitoneal injection of dextrose?
20gx1” needle, 60mL syringe, 50% dextrose, freshly boiled water, antiseptic spray, warming box, check temp
Dose: 10mL/kg of 2:3 solution of dextrose and H20
Site: 5cm caudal and 3cm lateral to navel, 20ga 1” needle, insert carefully at 90degrees
What is the aftercase after a dextrose dose?
individual box in a warm environment, carboard box is ideal (dispose after single use)
ewe nearby
How can we prefent hypothermia?
feed pregnant ewes well, have a draft free lambing area, check lambs and ewes frequently
What does diarrhea in lambs look like? At what age is it common? What can it be caused by?
in lambs <1mo
caused by organisms similar to cattle but diff strain
E. coli diarrhea
viral diarrhea - rotavirus
cryptosporidium
clostridium
What is clostridia in lambs?
obligate anaerobes
form spores - hardy and love lived
common in the enviro, particularly in soil contaminated w/ feces
some species produce toxins - some of most potent known
dz: kill rapid and difficult to tx
prevent by vx’s
Explain how clostridium perfringens affects lambs. What type? Signs? tx and prevention?
clostridium perfringes type C (or B) AKA lamb dysentery or type C enterotoxemia
usually lambs <3wks and prod a toxin that kills intestinal wall
Signs: sudden death, bloody diarrhea, severely toxemic, difficult to treat.
prevent by vx’inating dam about 6wks prior
antiserum can be given to lambs born to unvaccinated ewes during an outbreak
When do we see coccidiosis in lmabs? How do we treat?
seen in older lambs (2wks+) kept in crowded conditions
not usually bloody diarrhea
tx w/ deccox can be mixed in feed as a preventative
How does salmonellosis present in lambs? tx? prevent?
Zoonotic, causs diarrhea in sheep of all ages
very young lambs get the septicemic form and die w/o becoming diarrheic
ewes can abort
tx is supportive
prevent w/ good hygiene
How might parasites affect lambs? Signs? prevention?
Intestinal parasites an issue for lambs on grass or kept in pens in crowded conditions
Signs: poor growth, diarrhea, severe anemia if haemonchus sp. are the problem parasite
prevent by routine deworming w a mectin type dewormer @ end of june ( at minimum)
followed by moving to a clean pasture if at all possible, rotational grazing is key
What is C. perfringens type D enterotoxemia? Signs? Prevent?
pulpy kidney dz - gets name from rapid degeneration of kidneys following death in many lambs
seen in lams <2wks or weaned lambs in feedlots following switching to a high grain diet
Produces a toxin in the gut that’s absorbed and damages the brain
Signs: sudden death of best lambs is often first sign. Star gazing posture, circling, head pressing common neuro signs
Prevent by vx’ing ewes 6wks b4 lambing, control grain fed to lambs, give antiserumt o lambs in feedlot prior to change to high grain diet
How does polioencephalomalacia affect lambs? Signs? tx? prevention?
usually fed a high starch diet, cause is unclear but is related to a problem w/ thiamine (b1) (may be bacterial conversion of ruminal thiamine (vita B1) to an analog that is absorbed and blocks the function of thiamine
Signs: sudden onset, star gazing, extensor rigitiy, initially stand then recumbent.
Tx w/ very high doses of IV thiamine
Prevent by slow dietary changes
What should we suspect when there is sudden death in lambs vs any age?
lambs: enterotoxemia type B, C, and D
Any age: blackleg, lightning, anthrax
What is blackleg in lambs?
clostridium chauvoei infection of muscle, cna replicate in GI tract of sheep and contaminte pasture
seen in summer/fall
develops spontaneously in cattle - spores ingested in feed, migrate to muscle and remain dormant, sometimes activated w/ clinical signs.
In sheep spores directly contaminate wound and then replicate
What are the signs, tx and prevention of blackleg in lambs?
signs: sudden death, lameness, edem, crepitant swellings over any major muscle
tx: not very successful
prevent w/ vx’s, typically combo vx against all common clostridial dz’s given
Explain how anthrax works in sheep? How does it spread
Reportable. Forms spores when exposed to air and survive up to 50 yrs, particularly in soils that are alkaline, rich in nitrogen (organic matter) and are poorly drained
disturbing soil predisposes to outbreaks. Outbreaks also follow dry period then by flooding (as it dislodges concentrated spores, cattle/sheep drink standing water in flooded areas, and sorter length of pasture also predisposes bc sheep graze grass shorter than eq/cows)
What is the incubation period of anthrax in sheep? Signs? Treatment? Prevention?
Following ingestion spore develops, up to 14d incubation period
signs: die rapidly, blood oozes from orifices
tx w/ antibiotics if caught early enough
prevent by not opening carcasses (stain a blood smear for anthrax instead), move rest of herd and by live avirulent vx
