2 – Calving Management Flashcards
1
Q
Bos indicus vs. Bos taurus
A
- Bos indicus
o Tropical
o Bigger ears
o Hump
o More prepuce skin/area
2
Q
Discuss the objectives of calving management
A
- Minimize losses at birth
- Minimize post-natal losses
- Reduced disease in calving females
3
Q
How do you calculate calf crop percentage?
A
- (Number of calves weaned DIVIDED BY number of cows exposed to bull) MULTIPLY by 100
4
Q
What is the target of level for calf crop percentage?
A
- 85%
5
Q
What are the reasons for reduction in calf crop?
A
- Failure to
o Conceive
o Calve
o Survive neonatal period
o Wean
6
Q
Discuss the various factors contributing to neonatal losses
A
- *dystocia
- Maternal nutrition
- Maternal behaviour
- Climate (hypothermia)
- Infectious agents and environment
7
Q
What are the impacts of dystocia?
A
- 69% of preweaning mortality occurs within first 96hrs after birth
o 2/3 due to dystocia - 3% dues within 24hrs of birth
- If a difficulty calving=2.4x more likely to be sick in first 45 days of life
- 13x more likely to die within 12hrs of birth
8
Q
Who is most likely to experience dystocia?
A
- Calves born to 1st calf heifers
o 18% of heifers assisted - Males calves > female calves
- Twins
- Calves born to cows in poor body condition
9
Q
How can you prevent dystocia?
A
- Select bulls for low birth weights in calves
o Birth weights account for 30-50% of variability of dystocia rates - Easy calving breeds with heifers
- Use expected progeny differences (EPD) data on purebred bulls
- Those who had a LOW birth weight
10
Q
Expected progeny differences (EPD)
A
- Useful for comparing bulls within breed
- If birth weight EPD of +4, will have calves 5lbs heavier than bull with birth weight -1.0
- *need to know breed average for EPD (not usually 0, but pretty close)
- *accuracy value (between 0 and 1) as a measure of reliability
11
Q
Replacement heifer rearing to prevent dystocia?
A
- 65% of mature weight at breeding
- 85% of mature weight at calving
- Avoid over conditioning
- Do NOT restrict nutritional intake in late gestation
- Pelvic measurements are of limited value (hard to know a ‘good cutoff’, bigger pelvis=tend to have bigger calves)
12
Q
Adequate surveillance and early assistance for dystocia prevention?
A
- Can lead up to 9% increase in number of animals cycling at onset of breeding season and a 14% increase in fall pregnancy rate
- *early assistance increases likelihood of a live calf
13
Q
What happens during a normal stage 1 of calving?
A
- 3hrs-72hrs (cows less than heifers)
- Ligaments of pelvis relax
- Cervix and vagina dilate
- Cow separates from herd
- Tail raised, back arched, may start to strain
14
Q
What happens during a normal stage 2 of calving?
A
- Appearance of water bag
- Expulsion of calf through birth canal
- 30mins to 3 hours (cows less than heifers)
15
Q
What happens during a normal stage 3 of calving?
A
- Expulsion of fetal membranes
- Usually expelled within a few hours of birth
- Involution of uterus may take up to 40 days
16
Q
Calving heifers before cows (2-3 weeks) for dystocia prevention?
A
- Can concentrate workload early in calving season
- Heifers more likely to have dystocia or mismother
- Will calve on least contaminated calving area
- *need longer to return to estrus than cows
17
Q
When should we interfere?
A
- Cow actively straining for 40mins and NO progress made
- 90mins passed since the first waterbag appeared
- Legs emerge with the sole of hooves pointing up (backwards)
- Head or tail only emerges
- Cow demonstrated greater than 5-6hrs of anxiety
- Uncalved cow is mother another calf
18
Q
When should the producer call for help?
A
- Calf is too big
- Can’t get hands along side feet in pelvis
- Can’t get head and feet into pelvis at same time
- Heifer has been actively straining for 30mins and can’t get head and feet into birth canal
- If can’t correct position in 20mins or less
19
Q
What percentage of beef heifers require assistance at calving on average?
A
- 18%
20
Q
Weak calf syndrome: was in birth canal for too long
A
- Head and tongue swollen
- Likely wont get up and suck right away
- Acidotic
21
Q
**How to assess calf vigour: ‘weak calf syndrome”
A
- How long it takes to get from birth to STERNAL RECUMBANCY
- Assessing suckle reflex
22
Q
How long it takes to get from birth to sternal recumbency?
A
- Usually within 2-3 mins
- If takes more than 15mins=likely to be acidotic
23
Q
Calves suckling reflex
A
- If weak=41x of failing to consume colostrum within 4h after birth
- *used suckle reflex and calving ease to predict colostrum consumption by 4h after birth
- *very important for immunity and preweaning health of beef calves
24
Q
Assessing suckle reflex
A
- 10mins after birth
- 2 fingers along length of top of calf’s tongue
- Gently rub the roof of mouth
- Poor jaw tone, poor suckling rhythm=weak
- Good jaw tone, good rhythm, quick latch=strong suckle reflex
25
If a hard pull and failure of colostrum consumption: %’s
- 64%
o If strong suckle reflex=49%
o If weak suckle reflex=98%
26
Abnormal maternal behaviour (AMB)
- 1st heifers more likely
- Heifers and calves with dystocia more likely
- Prolonged birth more likely
- *less vigorous calf result in AMB
- High incidence can come from poor condition of cows
27
How do you ‘treat’ abnormal mothering behaviour?
- Match the cows and calf correctly
- Confinement in a box stall wehre there are no disturbances
- Tube the calf with colostrum
- Restrain cow regularly so calf can suck
- Make sure calf is not obviously sick
28
Hypothermia
- Calf within first 2-3hrs is unable to regulate body temperature very well
- *happens to even normal calves
- Chilled calves will NOT get up, suckle and make use of colostrum
29
Climatic/seasonal effects: calves born from December to March were
- 4x more likely to die within 24hrs of birth
- 2x more likely to have diarrhea
- *calves admitted that were hypothermic are 4.3x more likely to DIE
30
How do you know if you need to move a calf indoors after 3hrs from birth so it’s not too cold?
- *did the calf suckle? Look at the COW: teat shinny and smaller quarter
- Take TEMPERATURE
31
Hypothermia protocol: measurements
- Electronic thermometer is essential to note the severity of hypothermia
- Calves <35degree: have cold mouth, limbs and no suck reflex and are unable to move limbs
- Calves >37.8 degree = NORMAL
- *consider using duct tape to protect ears from freezing
32
What do you do if a calf is less than 35 C?
- Tube with 1-2L of warm colostrum
- Place in warm room or ‘hot box’
- *Hot water baths essential for calves less than 26C
- Warm fluids IV, warm water enemas
33
**Describe management strategies for reducing infection pressure
- Minimize confinement of cow herd
- Utilize separate wintering and calving areas
- Move cows onto calving area 2 weeks before calving
- Rotate calving area from year to year
- Snow removal and adequate bedding
- Separate nursery areas for cow-calf pairs
- Avoid restricted feeding/bedding areas
- Creep areas or ‘calf condos’
- Quarantine of diarrheic calves
34
What is the Lacombe-type management system for groups of 100-200 cows?
- Wintering areas
- Move cows 2 weeks before calving
- Calving area 100-200 cows ~20acres
- Move pairs within 24 hrs of calving
o 2 nursing areas of 35-50 pairs, 10-12 acres
- At 3-4 weeks of age move to summer pasture
35
What is the sandhill calving system?
- Overwinter (500cows)
- Multiple calving areas
- *cow calf pairs are LEFT behind, pregnant cows MOVED to next clean calving area
