Transcript 2002 ANS 110

Sequence of Major Events : Dairy Cattle
Reproductive Cycle
Calving
82 d
Calving
283 d
---------------------------------------------------------------Pregnant
Not Pregnant
Lactation Cycle
305 d lactation
Calving
Calving
60 d
----------------------------------------------------------------“Dry”
120
Milk
lb/day
Lactation Curve
90
60
30
60
90
Days Postpartum
305
Dry
Sequence of Reproductive Events in Dairy Cattle
1st Parturition - 1100 - 1150 lb
90 lb
birth
<-----
800 lbs Conception
1.5
3
Weaning
24
6
15
9
12
Puberty
(550 - 600 lb)
<---Months--->
Sequence to reach calving at 24 months
Parturition
• Relaxin causes relaxation of ligaments in
pelvic region
• Cervix relaxes from tightly closed state
during pregnancy
• Expulsion of fetus through vaginal passage
Calving Environment
• Clean, dry area
• Pasture environment, if
applicable
• Close to center of activity
to allow for observation
• Ability to milk a cow in
calving area
• Method for lifting animal
up
Dystocia
• Difficulty in calving
• Incidence is influenced by birth weight of calves,
proper presentation of calf, sire of calf
• Affects risk of calf mortality
• Incidence in heifers calving for the first time is ~
8-9% for Holsteins
– Use of calving ease sires can reduce incidence in
heifers
Postpartum Care of the Calf
• Ensure the calf is breathing
• Disinfect the navel with 7% iodine
• Identify the calf (ear tag, tattoo, other)
• Remove calf from cow
– Minimizes risk of disease transfer
– Decreases calf mortality and morbidity
COLOSTRUM
•First milk secretion produced by cow at calving
•“colostrum” for 1 d after calving
•“transition milk” at 2-3 d after calving
* High in antibodies that protect young from
invading microorganisms
Postpartum care of calf II
• Provide injections of vitamins as needed
• Feed Colostrum
– 2-3 quarts within 30 min – 1 h after
birth
– Another 2-3 quarts within first 12 h of
life
Colostrum and milk composition
Holstein
Item
1st milking 2nd milking
Milk
Total solids
23.9
17.9
12.9
Fat
6.7
5.4
3.7
Casein
4.8
4.3
3.8
Lactose
2.7
3.9
5.0
Minerals
1.1
1.0
0.7
Immunoglobulins
6.0
4.2
0.09
Vitamin A
295
190
34
IMMUNOGLOBULIN ABSORPTION
Blood Vessel
-------------------------------------------------------------------------------------------
----
------------ ---------
Gastro Intestinal
Tract at
Birth
------Blood Vessel
------------------------Gastro Intestinal
Tract at 24 hours
After Birth
--------------- ----------
-----
-------------------------------------- -------------- ----------------Globulin
------ cannot pass through the intestinal wall unchanged
Colostrum Source
• Older Cows
– First Lactation ~5.9 % Antibodies
– Third Lactation ~ 8.2 % Antibodies
• Vaccinated Cows
• Healthy Cows
– Johne’s Free
– Bovine Leukosis Virus - Free
Feeding Calves
• Waste Milk vs. Milk
Replacer
– 8 to 10 % of body
weight
– Depends on housing
Feeding calves
• Offer Quality Starter starting < 2 wks of age
– Stimulate Rumen Development
• Offer Water
• Typically will not feed hay or silage until
after weaning if complete starter is used
Development of the bovine stomachs
Birth
3-6 mos
Maturity
Rumen
25%
65%
80%
Reticulum
5%
5%
5%
Omasum
10%
10%
7-8%
Other management practices
• Dehorn
• Remove extra teats
• Additional
Identification
– Written file with ID
number, DOB, sire,
dam, condition at birth
• Vaccinations
Calf Housing
• Individual Housing
– Hutches
– Cold Confinement
– Warm barns
• Draft Free
• Proper Ventilation
• Dry Bedding
Immunity to disease
• Natural at birth
– Inherited: species, racial/group, individual
– Acquired in vitro
• Acquired
– Natural, disease
– Artificial
• Active – vaccine
• Passive - colostrum
Calfhood diseases
• Scours
– Characteristics
– Causes
• Bacteria - infectious
• Nutrition - noninfectious
• Respiratory diseases
– Pneumonia
• Lung damage, death