PENGARUH KOMBINASI PROBIOTIK DAN BELIMBING WULUH (Averrhoa bilimbi L) DALAM AIR MINUM TERHADAP MORFOMETRIK, HISTOMORFOMETRIK USUS HALUS, DAN PERFORMA AYAM ALOPE UNHAS 1

Khaerunnisa. The Effect of a Combination of Probiotics and Star Fruit (Averrhoa bilimbi L.) in Drinking Water on Morphometry, Histomorphometry of the Small Intestine, and Performance of Alope Unhas 1 (Supervised by Sri Purwanti and Wempie Pakiding). Native chickens are a source of local Indonesian poultry genetic resources that are well-adapted to tropical environments and traditional rearing systems. One promising breed is the Alope Unhas 1 chicken, developed by the Faculty of Animal Science at Hasanuddin University as part of efforts to conserve genetic resources while improving productivity. Optimizing the performance of the Alope Unhas 1 chicken is influenced not only by feed quality but also by the use of natural feed additives that support gastrointestinal function. This study aimed to evaluate the effect of a combination of probiotics and bilimbi (Averrhoa bilimbi L.) in drinking water on the growth performance as well as the morphometric and histomorphometric characteristics of the small intestine of Alope Unhas 1 chickens. This study used five treatments: P0 (control), P1 (1 mL/L probiotic + 0.5% bilimbi), P2 (1.0%), P3 (1.5%), and P4 (2.0%). The parameters observed included feed intake, weight gain, feed conversion ratio, small intestine morphometric parameters (percentage of ileal weight and the lengths of the duodenum, jejunum, and ileum segments), and histomorphometric parameters (villus height, crypt depth, and villus-to-crypt ratio).The results showed that the treatments had a significant effect (P < 0.05) on growth performance, small intestine morphometry, and histomorphometry. Treatment P4 yielded the best performance with a feed intake of 300 g/bird/week, a body weight gain of 153 g/bird/week, a feed conversion ratio of 2.25, and increases in villus height (1329.18 µm) and the villus-to-crypt ratio (4.12). Ileal weight and the total length of the small intestine segments increased significantly, indicating morphofunctional adaptation of the distal intestine. The combination of probiotics and 2% star fruit has the potential to serve as a natural feed additive to promote growth in Alope Unhas 1