ưu điểm và nhược điểm

ưu điểm và nhược điểm

Kết quả (Anh) 1:

Advantages and disadvantages

Kết quả (Anh) 2:

Positive and weaknesses

Kết quả (Anh) 3:

The objective of this study was to evaluate the effect of particle size in pelleted diet on nutrient digestibility andgrowth performance of weaning piglets. 352 uncastrated males, aged 28 to 63 d, were distributed in a randomized block design (initial weight) according to treatments. The experimental feeds were divided into twophases, pre-initial (28 to 42 d) and initial (43 to 63 d) and produced with different corn particle sizes ground in ahammer mill, which provided a geometric mean diameter (GMD) of 394 μm, 534 μm, 647 μm, and 695 μmrespectively, to the pre-initial phase diets. In the initial phase the GMD was 587 μm, 625 μm, 798 μm, and 943μm. All feeds were pelleted (pellet diameter 2.5 mm) and supplied ad libitum. After an analysis of variance (P <0.05), orthogonal contrasts were constructed to evaluate the linear and quadratic effect of increasing feedparticle size on digestibility and growth performance. In the pre-initial phase, there was no difference in dailyfeed intake and daily weight gain between treatments; however, there was a quadratic response (P < 0.05) infeed/gain ratio, and the reduction of GMD to 534 μm was positively correlated with feed/gain ratio. In the initialphase, feed intake increased linearly (P <0.05) with increasing GMD in the pelleted diet. GMD had no effect onfeed/gain ratio, but there was a linear correlation (P <0.05) between GMD and weight gain in this phase, owingto greater feed consumption. There was a linear response (P <0.05) in dry matter and ether extract digestibilitycoefficients, with the highest values determined in pigs consuming the finest diets (587 μm). GMD had no effecton crude protein digestibility, but there was a quadratic correlation (P < 0.05) between particle size anddigestible energy, as digestible energy reduced as GMD increased to 798 μm, followed by a slight increaseat 943 μm. In conclusion, as the weaning pigs become older, their growth performance response increases withincreasing particle size of the pelleted diet. The GMD for an optimal pelleted feed is 534 μm for pre-initial and943 μm for initial phase. Additionally, during the initial phase, fine particle sizes results in better efficiency offeed utilization.