cattle fertility

Question 1

what are the three available sync programmes for cattle

Answer 1

1. prostaglandin programmes
2. CIDR basic programme
3. CIDR-sync protocol

Question 2

which is suitable for cycling animals and which is suitable for non cycling animals

Answer 2

prostaglandin and CIDR basic programme is suitable for cycling animals only

CIDR-sync programme is suitable for both cycling and non cycling animals

Question 3

what are the three breeding strategies that can be used

Answer 3

1. natural mating
2. AI to those observed in heat
3. fixed time artificial insemination

Question 4

describe the prostaglandin programme

Answer 4

inject all individuals with a CL on their ovary with prostaglandin to initiate luteolysis. Over the next 11-14 days observe the herd for signs of heat. Any individuals seen bulling can be give AI during this period. For the individuals not given AI by the end of the 11-14 day period give them a second injection of PGF2. This is then followed up by fixed time AI at 72 and 96 hours after the second injection. This programme is often used in heifers

Question 5

Describe the CIDR basic programme

Answer 5

day 0= insert CIDR
day 7= inject with PGF2
day 8= remove CIDR

following removal of CIDR heat detect and AI following a fixed time AI at 56hrs post removal for any unserved animals

Question 6

describe the CIDR-sync programme

Answer 6

day 0 (AM)= insert CIDR and give GnRH injection
day 7 (AM)= give prostaglandin injection
day 8 (AM)= remove CIDR
36 hours later (PM)=GnRH injection
16-20 hours later give a fixed time AI service

Question 7

what can be used following the CIDR-sync programme to inseminate missed cows

Answer 7

clear up bulls can be introduced 14 days following AI to allow natural mating of any empty females

Question 8

how would you induce abortion in cattle/heifers

Answer 8

up to 150 days PGF2 is given to induce abortion of unwanted pregnancies.
any pregnancies later than 150 days require a combination of PGF2 and glucocorticoids to induce abortion.

*Inducing abortion in heifers that are >4 months into pregnancy is risky and can result in very dry and difficult abortions that may risk loosing the heifer. It is recommended to let the cow go to term and caesarean

Question 9

what are the infectious causes of abortion in cattle

Answer 9

1. blutongue
2. BVD
3. Brucellosis
4. campylobacter fetus veneralis
5. Chlamydia abortus
6. IBR
7. Leptospirosis
8. Listeria
9. Trichomonas
10. Neospora
11. salmonella
12. Mycotic
13. trueperella pyogenes
14. Bacillus licheniformis

Question 10

descibe BVD infections relating to stage in pregnancy and the effect this has on the fetus

Answer 10

infection <95 days= embryonic death/abortion

infection 95-120 days prgenancy= PI calf

infection >120 days= seropositive foetus, congenital lesions, abortion due to placentitis

Question 11

describe campylobacteriosis

Answer 11

campylobacter fetus venerealis
an STD comon in beef herds using natural mating. Rare in dairy.
causes chronic endometritis and abortions between 4 and 8 months gestation.
Important to test bulls beforehand

Question 12

what are the infective causes of viral vaginitis

Answer 12

IBR and BHV 1 and 2

Question 13

when does lepto and listeria cause abortions

Answer 13

second half of pregnancy
(4 months onwards)

Question 14

what disease process resulting in abortion is seen with bacillus licheniformis infection

Answer 14

necrotizing placentitis

Question 15

how is neospora transmitted

Answer 15

both horizontally and vertically

dog-cow-fetus
cow-fetus
dog-cow-dog-cow

Question 16

what are the different outcomes of neospora infection during different stages of prgenancy

Answer 16

1st trimester= early embryonic death
2nd trimester= abortion or PI calf with congenital defects
3rd trimester= PI calf, can have brain defects or be normal

Question 17

what is an endemic and epidemic abortion rates in herds affected with neospora

Answer 17

endemic=>3% abortion rate
epidemic=>10% abortion

Question 18

what is trichmoniasis

Answer 18

veneral disease of cattle caused by protozoan parasite tritrichomonas foetus which is spread by infected bulls. the disease reduces calf production by decreasing fertility and inducing abortions

Question 18

how is neospora controlled

Answer 18

endogenous transmission
identify seropositive cows by either serology of whole herd or test calves at birth.
cull infected cows or selectivley breed and sell infected calves for beef. no cow-cow transmission therefore this is a viable option

exogenous transmission
reduce risk of infection of dogs by disposing afterbirth or aborted material carefully.
minimise contamination of cattle feed with dog feaces.
Biosecurity!