No abstract

Geese are extremely adept in utilizing plant-derived roughage within their diet. However, the intestinal microbiome of geese remains limited, especially the dietary effect on microbial diversity. Cassava foliage was widely used in animal feed, but little information is available for geese. In this study, the geese were fed with control diet (CK), experimental diet supplemented with 5% cassava foliage (CF5) or 10% (CF10) for 42 days, respectively. The cecal samples were collected after animals were killed. High-throughput sequencing technology was used to investigate the microbial diversity in the caecum of geese with different dietary supplements. Taxonomic analysis indicated that the predominant phyla were distinct with different dietary treatments. The phyla Firmicutes (51.4%), Bacteroidetes (29.55%) and Proteobacteria (7.90%) were dominant in the CK group, but Bacteroidetes (65.19% and 67.29%,) Firmicutes (18.01% and 17.39%), Proteobacteria (8.72% and 10.18%), Synergistete (2.51% and 1.76%) and Spirochaetes (2.60% and 1.46%) were dominant in CF5 and CF10 groups. The abundance of Firmicutes was negatively correlated with the supplementation of cassava foliage. However, the abundance of Bacteroidetes and Proteobacteria were positively correlated with the supplementation of cassava foliage. Our study also revealed that the microbial communities were significantly different at genus levels. Genes related to nutrient and energy metabolism, immunity and signal transduction pathways were primarily enriched by the microbiome.

To better understand the mechanism underlying the citric acid (CA)-regulated silage fermentation, we investigated the bacterial community and fermentation quality of king grass (KG) ensiled without (CK) or with Lactobacillus plantarum (L), CA and the combination of L and CA (CAL). The bacterial community was characterized by using the 16Sr DNA sequencing technology. The L and CA treatments altered the silage bacterial community of KG, showing reduced bacterial diversity, while the abundance of desirable genus Lactobacillus was increased, and the abundances of undesirable genus Dysgonomonas and Pseudomonas were decreased. The additives also significantly raised the lactic acid content, dropped the pH, and reduced the contents of acetic acid, propionic acid, and ammonia-N in ensiled KG (P < 0.01). Besides, the combination treatment was more effective on silage fermentation with the highest pH and lactic acid content, while the contents of acetic acid, propionic acid, and ammonia-N were the lowest (P < 0.01). Moreover, CAL treatment exerted a notable influence on the bacterial community, with the lowest operational taxonomic unit (OTU) number and highest abundance of Lactobacillus. Furthermore, the bacterial community was significantly correlated with fermentation characteristics. These results proved that L and CA enhanced the KG silage quality, and the combination had a beneficial synergistic effect.

In order to improve the silage fermentation of stylo (Stylosanthes guianensis) in tropical areas, stylo silages were prepared with commercial additives Lactobacillus plantarum Chikuso-1 (CH1), L. rhamnasus Snow Lact L (SN), Acremonium cellulase (CE) and their combination as SN+CE or CH1 + CE, and the fermentation quality, chemical composition and ruminal degradation of these silages were studied. Stylo silages treated with lactic acid bacteria (LAB) or cellulase, the pH value and NH -N ⁄ total-N were significantly (P < 0.05) decreased while the ruminal degradability of dry matter (DM), crude protein (CP), neutral detergent fiber (aNDFom) and acid detergent fiber (ADFom) were significantly (P < 0.05) increased compared to control. Compared to LAB or cellulase-treated silages, the DM, CP contents and relative feed value (RFV), and the ruminal degradability in LAB plus cellulase-treated silages were significantly (P < 0.05) higher, but the aNDFom content was significantly (P < 0.05) lower. CH1 + CE treatment was more effective in silage fermentation and ruminal degradation than SN+CE treatment. The results confirmed that LAB or LAB plus cellulase treatment could improve the fermentation quality, chemical composition and ruminal degradation of stylo silage. Moreover, the combined treatment with LAB and cellulase may have beneficial synergistic effects on ruminal degradation.

As the by-product of cassava, cassava foliage (CF) has been widely used in livestock feed. However, little information is available on its utilization for geese. In this study, we aimed to investigate the effects of CF on the feed digestion, meat quality, and antioxidative status of geese. A total of 108 male Hainan indigenous geese (28-days-old) with similar body weight were randomly and evenly divided into 3 groups, and the geese were fed for 42 D on either the control diet (CON) consisting of ground maize, soybean meal, and wheat bran, or the experimental diet composed of ground maize, soybean meal, and wheat bran supplemented with 5% (CF1) or 10% (CF2) CF. Dietary nutrient digestibility, physicochemical properties, amino acid and fatty acid composition of meat, and antioxidative status of geese were evaluated. The results showed that supplementation of CF in goose diets enhanced the feed digestion and affected the meat quality. In addition, supplementation of CF had beneficial effects on the regulation of amino acid and fatty acid profiles in muscle tissues. Moreover, such supplementation had no significant effect on antioxidative status. Taken together, goose diet containing 5% CF was recommended based on feed efficiency and meat quality.