Biology

Question 1

What do enzymes, bacteria, protozoa, and fungi produce in the rumen? Specifically, what kinds of these products?

Answer 1

VFAs. Acetic, propionic, and butyric

Question 2

How is glucose utilized in ruminants? How is this different from many other animals?

Answer 2

VFAs are the main energy source, instead of glucose. Glucose is produced from propionic acid, or amino acids, for metabolism in the CNS, uterus, and mammary gland.

Question 3

What produces do rumen microorganisms produce?

Answer 3

B-complex vitamins, vitamin K, and protein

Question 4

For how long is intestinal immunoglobulin absorption active in neonates?

Answer 4

36 hours

Question 5

How many major ovine histocompatibility classes have been identified?

Answer 5

Three. Ovis aries Class I, II, and III

Question 6

How does knowledge regarding the bovin lymphocyte antigen system rank?

Answer 6

BOLA ranks after human and murine systems in terms of depths of knowledge.

Question 7

How is the ruminant eye unique?

Answer 7

Bovine corneal epithelium has ability to heal without treatment, even when severely infected. Corneal ulcers uncommon in sheep and goats.

Question 8

What WBC predominates in ruminants?

Answer 8

Lymphocytes, over neutrophils

Question 9

Why can BUN not be used as an indicator of renal function?

Answer 9

Metabolism of urea nitrogen by rumen microflora

Question 10

Are ruminants prone to dehydration? What is a concern about rehydration?

Answer 10

No, adult ruminants can go several days without drinking before sig. dehydration occurs. RBCs may become more fragile during rehydration, resulting in some degree of hemolysis and hemoglobinuria.

Question 11

What is unique regarding ruminant erythrocytes?

Answer 11

Smaller and more fragile than in most other mammals. Hematocrits tend to be overestimated unless blood samples centrifuged for extended periods of time.

Question 12

What is urine pH generally in ruminants?

Answer 12

Alkaline

Question 13

What species demonstrate rouleaux formation?

Answer 13

Not cattle, to a limited extent in sheep and goats.

Question 14

Describe normal caprine erythrocytes.

Answer 14

Lack central pallor because they are flat and lack biconcavity. May exhibit poikilocytosis.

Question 15

Describe liver enzymes in ruminants.

Answer 15

AST and LDD not liver specific in ruminants
ALT cannot be used to evaluate hepatic disease in goats
GGT and AP associated with biliary stasis
GGT elevations generally associated with hepatic damage

Question 16

Describe blood groups in sheep and goats.

Answer 16

Seven identified in sheep, at least five in goats.

Question 17

Describe blood transfusions in ruminants.

Answer 17

Reactions may be as high as 2-3%. Cross-matching advisable, but not always practical.
Obtain volumes of 10 m/kg, give in volumes of 10-20 ml?kg

Question 18

What steps can be taken to reduce the risk of blood transfusions in sheep?

Answer 18

Obtain blood products from a single donor, perform a crossmatch prior to transfusion, and use synthetic products to increase oxygen carrying capacity of fetal blood.

Question 19

Describe reproduction in sheep and goats. How can ewes be stimulated to progress from anestrus to estrus?

Answer 19

Seasonally polyestrus, short-day breeders. Stimulate via maintaining in 8h of light and 16h of darkness for 8-10 weeks.

Question 20

Which ewes tend to be more prolific?

Answer 20

Older ewes tend to have multiples, as do Finn and Dorset breeds.

Question 21

When do cattle, sheep, and goats reach puberty?

Answer 21

Cattle: 4-18 months, mean 12
Sheep: 7-8 months
Goat: 4-8 months

Question 22

What is the duration of the cycle for cattle, goats, and sheep?

Answer 22

Cattle: 18-24 days (21)
Sheep: 14-19 days (17)
Goats: 18-24

Question 23

What is the length of estrus for cattle, sheep, and goats?

Answer 23

Cattle: 10-24 hours (18)
Sheep: 24-30 hours
Goat: 24-96 hours (40)

Question 24

What is the gestation length in cattle, sheep, and goats?

Answer 24

Cattle: 270-292
Sheep: 147-150
Goats: 144-155

Question 25

What clinical signs do ewes in heat display? What is the most reliable method to detect estrus? Detect pregnancy?

Answer 25

Show a mild enlargement of the vulva with slight increase in mucus secretion. Most reliable to use sterile ram to mark females when they are in standing heat. Transabdominal U/S or interrectal doppler probes for preg. detection. Accuracy best beyond 60 days of gestation. Commercial tests for serum pregnancy-specific protein B can confirm pregnancy beyond approx. 30 days in sheep and goats.

Question 26

What are signs of estrus in goats? How can does be induced to ovulate? How should does be bred?

Answer 26

Signs include uneasiness, tail switching or flagging, redness and swelling of the vulva, clear vaginal discharge that becomes white by the end of estrus, and vocalization. Can be induced to show signs of heat by buck exposure, and will ovulate within 7-10 days after introduction of buck. Most ovulate between 24-36 hours after estrus and should be mated once signs of estrus are recognized and every 12h until the end of estrus.

Question 27

What are signs of estrus in cattle? How long does the hallmark sign last? When and how can pregnancy be determined?

Answer 27

Hallmark in standing to be mounted. Lasts 12-15h, with range of 6-24h. Ovulation 12-18h after onset of estrus. Other methods are blood progesterone, change in conductivity of cervical mucus, change in vaginal pH and body temp, and evaluating activity with pedometry. U/S detects at 28-32 days, fetal gender at day 55. Via rectal palpation at 30-40 days. Commercial serum or milk tests also available.

Question 28

Describe parturition in ewes.

Answer 28

Once hard contraction begin, lambs usually born quickly.

Question 29

Describe parturition in does. How might large facilities attempt to control the onset of parturition.

Answer 29

If labor is prolonged for more than 1 hour, vaginal exam is indicated. On day 144 of gestation, goats given PGF2a will deliver kids within 28-57 hours.

Question 30

Describe pseudopregnancy in does.

Answer 30

One of few ungulate species that commonly has false pregnancies. May have distended abdomens, develop hydrometra, and deliver large volumes of cloudy fluid at expected due date. Subsequent pregnancies can still be normal.

Question 31

Describe parturition in cattle.

Answer 31

Cow will separate from the herd. Will lift her tail and arch her back when she is within a few hours. Most are recumbent during delivery. Process typically takes about 100 minutes, longer for cows with larger calves or primiparous animals. Monitor for delivery of membranes w/i 12 hours of birth. Not recommended to manually remove placenta or place intrauterine boluses.

Question 32

At what age are calves, lambs, and kids weaned?

Answer 32

Lambs: As early as 4 weeks, 6-8 weeks more common Kids: 6-10 weeks, or 18-25 pounds Dairy calves: Usually immediately removed, with milk replacer or whole milk until 4-7 weeks.

Question 33

What is the pregnancy rate of embryo transfers?

Answer 33

About 70%

Question 34

How successful is AI in dairy herds?

Answer 34

As high as 70% with frozen semen. Guelph System for transcervical AI results in successful penetration into the uterus for up to 75% of ewes.

Question 35

Describe aging of sheep via their teeth.

Answer 35

At birth, have eight baby/milk teeth on lower jaw. At each successive year, pair of baby incisors is replaced by a permanent pair. Full mouth of teeth by 4. As they age, incisors start to spread and breath down. Process is similar for goats. Cattle are also similar, but they don't get their first permanent incisors until 2 years old and their adult teeth until 4-5 years.