883
Effects of oral calcium supplementation on body temperature, incidence of uterine diseases, and milk yield in dairy cows
Objectives were to determine the effects of oral Ca supplementation (CaS) on the incidence of uterine diseases in dairy cows considered at low (LRM; normal calving) or high risk (HRM; dystocia, twins, stillbirth, retained placenta and/or vulvo-vaginal laceration >3 cm) of developing metritis. The hypotheses were that oral CaS with boluses containing CaCl2 and CaSO4- (each containing 43 g of Ca) during the first 4 DIM maintain blood ionized Ca (Ca2+) concentrations ≥ 1.0 mM and reduce the incidence of uterine diseases regardless of risk of metritis. In this randomized complete block design, HRM cows (n=225) were matched with LRM (n=225) on the day of calving based on parity. Each pair of matched cows was randomized to one of three treatments: CaS0, no Ca supplementation; CaS2, 2 boluses at 0 and 1 DIM; CaS4, 2 boluses at 0 and 1 DIM followed by 1 bolus at 2, 3, and 4 DIM. Blood Ca2+ was measured in a subset of cows (n=60) before the first bolus administration and 35 min after each dose for the first 4 DIM using a Vetscan Istat handheld analyzer (Abaxis). Rectal temperature and vaginal discharge were monitored in the first 10 DIM. Metritis was defined as fetid, watery vaginal discharge, and puerperal metritis (PuMet) was defined as metritis with rectal temperature ≥ 39.5°C. Endometritis was considered as mucopurulent vaginal discharge. Milk yield was evaluated weekly during the first 30 DIM. Cows with at least one corpus luteum in 2 ultrasounds performed 2 weeks apart beginning on 38 DIM were considered cyclic. Data were analyzed using PROC GLIMMIX and PROC GENMOD of SAS. Oral supplementation with Ca during early postpartum increased blood Ca2+concentrations; however, the two regimens of Ca supplementation failed to reduce the incidence of metritis in either HRM or LRM groups.
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Treatment |
|
|
||||||
|
CaS0 |
CaS2 |
CaS4 |
SE |
P |
||||
|
HRM |
LRM |
HRM |
LRM |
HRM |
LRM |
|
|
|
|
|
|
|
|
|
|
|
|
|
Ca2+, mM |
1.08a |
1.09a |
1.15b |
1.17b |
1.21c |
1.20c |
0.02 |
<0.01 |
|
Temperature, ˚C |
38.87 |
38.76 |
38.91 |
38.77 |
38.90 |
38.74 |
0.03 |
0.60 |
|
Milk, Kg/d |
29.4 |
32.9 |
29.4 |
30.7 |
27.7 |
32.1 |
1.1 |
0.35 |
|
Uterine Diseases |
%(n/n) |
|
|
||||||
Metritis |
56.0(42/75) a |
10.7(8/75) a |
64.0(48/75) b |
21.3(16/75) b |
55.4(41/74) a |
21.3(16/75) a |
|
<0.01 |
|
PuMet |
14.7(11/75) |
1.33(1/75) |
18.7(14/75) |
5.33(4/75) |
18.9(14/74) |
6.7(5/75) |
|
0.30 |
|
Endometritis |
39.1(27/69) |
23.2(17/73) |
33.3(24/72) |
21.6(16/74) |
32.4(23/71) |
19.2(14/73) |
|
0.59 |
|
Cyclicity 52 d |
71.0(49/69) |
73.3(55/75) |
75.3(55/73) |
81.3(61/75) |
69.4(50/72) |
78.1(57/73) |
|
0.42 |
|
a,b,c different superscripts indicate differences among treatments (P<0.05)
Keywords:
Dairy cows, Ca supplementation, metritis