1845
Replacement of soybean meal by high energy cottonseed meal in diets of dairy cows: milk production and Ovarian follicular dynamics
Supply of high biological value protein is key to reproductive and productive performance, however the cost is high. The aim of this study was to evaluate replacement of soybean meal by high energy cottonseed meal like protein source in dairy cows diets on productive and reproductive parameters. Five Girolanda cows with average body weight of 530 kg, distributed in 5x5 Latin square were used (5 levels of substitution of soybean meal by high energy cottonseed meal: 0% (FA0), 15% (FA15), 30% (FA30), 45% (FA40) and 60% (FA60) and 5 periods). Each period lasted 18 days. Milk production (MP) and body score condition (BSC) were evaluated on the 18th day and ovarian evaluations (number of recruited follicles (NRF), dominant follicle diameter (DFD), and corpus luteum diameter (CLD)) were conducted from 7 to 18th day of supplementation by trans-rectal ultrasonography. Data were analyzed by Tukey test with 5%of significance level.
Table 1: Milk production (MP, kg/day), body score condition (BSC, 1-5), number of recruited follicles (NRF), dominant follicle diameter (DFD, mm), and corpus luteum diameter (CLD, mm) of Girolanda cows feeding with diets with substitution of soybean meal by high energy cottonseed meal
Treatment |
MP |
BSC |
NFR |
FMD |
CLD |
FA0 |
14.4±0.2a |
2.9±0.03 |
25.69±1.22 |
15.10±0.39 |
20.60±0.7 |
FA15 |
12.4±04c |
2.9±0.07 |
26.08±1.31 |
17.90±0.64 |
21.15±0.7 |
FA30 |
14.6±03a |
2.9±0.05 |
26.83±1.12 |
16.90±0.33 |
21.85±0.6 |
FA40 |
14.5±0.2a |
2.9±0.03 |
25.89±1.28 |
14.90±0.34 |
21.10±0.9 |
FA60 |
13.7±04b |
2.9±0.07 |
26.08±1.01 |
18.30±0.32 |
20.40±1.0 |
P |
<0.0001 |
0.3002 |
0.8133 |
0.1039 |
0.6781 |
Legend: FA: diet without substitution; FA15 replacement 15% of soybean meal by high energy cottonseed meal; FA30 replacement 30% of soybean meal by high energy cottonseed meal; FA40 replacement 40% of soybean meal by high energy cottonseed meal; FA60: replacement 60% of soybean meal by high energy cottonseed meal; P: significance level
A, b, c…different letters in same column indicate differences by Tukey test
Replacement of protein source (replacement of soybean meal by high energy cottonseed meal) do not influenced (p > 0.05) body score condition, number of recruited follicles, dominant follicle diameter, and corpus luteum diameter. However, could reduce milk production in higher and lower replacements levels (Table 1). The replacement of soybean meal by high energy cottonseed meal as protein source at level of 30 or 40% is feasible because not alters reproductive and productive performance, and promotes reduced diet cost.
Keywords: Protein sources, follicles, girolando