Modification of dietary rumen degradable starch content by chemical processing of feed ingredients: A meta-analysis.

The efficiency of starch utilization in ruminant feed can be enhanced by reducing the degradation of starch in the rumen. Chemical processing of feed ingredients may modify such ruminal starch degradation. This study aimed to evaluate the chemical processing of ruminant feed ingredients on rumen degradable starch (RDS) and starch degradation kinetics in the rumen. A database was constructed from a total of 34 articles, consisted of 100 observations. The articles were searched and identified from the Scopus platform. Data were analyzed by using the fixed effect model. The types of chemical processing in this study included sodium hydroxide, ammonia, potassium aluminum, urea, formaldehyde, and organic acid. Results indicated that chemical processing significantly reduced the RDS content (p < 0.001) and the immediately soluble fraction (p < 0.001) and increased the value of slowly degradable fraction (p < 0.001) and starch absorption in the small intestine (p < 0.01). Formaldehyde was particularly effective to decrease the RDS (p < 0.05). The RDS contents in corn and wheat were reduced by the chemical processing (p < 0.05), but not with that of barley. It can be concluded that chemical processing is effective in reducing starch degradation of ruminant feeds and may enhance its utilization by ruminants.

Evaluation of Megasphaera elsdenii supplementation on rumen fermentation, production performance, carcass traits and health of ruminants: a meta-analysis.

OBJECTIVE: This study was conducted to evaluate the use of Megasphaera elsdenii (M. elsdenii) as a probiotic on rumen fermentation, production performance, carcass traits and health of ruminants by integrating data from various related studies using meta-analysis. METHODS: A total of 32 studies (consisted of 136 data points) were obtained and integrated into a database. The parameters integrated were fermentation products, rumen microbes, production performance, carcass quality, animal health, blood and urine metabolites. Statistical analysis of the compiled database used a mixed model methodology. Different studies were considered random effects, while M. elsdenii supplementation doses were considered fixed effects. p-values and the Akaike information criterion were employed as model statistics. The model was deemed significant at p<0.05 or had a tendency to be significant when p-value between 0.05〈p〈0.10. RESULTS: Supplementation with M. elsdenii increased (p<0.05) some proportion of fermented rumen products such as propionate, butyrate, isobutyrate, and valerate, and significantly reduced (p<0.05) lactic acid concentration, acetate proportion, total bacterial population and methane emission. Furthermore, the probiotic supplementation enhanced (p<0.05) livestock production performance, especially in the average daily gain and body condition score. Regarding the carcass quality, hot carcass weight and carcass gain were elevated (p<0.05) due to the M. elsdenii supplementation. Animal health also showed improvement as indicated by the lower (p<0.05) diarrhoea and bloat incidences as well as the liver abscess. However, M. elsdenii supplementation had negligible effects on blood and urine metabolites of ruminants. CONCLUSION: Supplementation of M. elsdenii is capable of decreasing ruminal lactic acid concentration, enhancing rumen health, elevating some favourable rumen fermentation products, and in turn, increasing production performance of ruminants.

Frailty as a mortality predictor in older adults with COVID-19: A systematic review and meta-analysis of cohort studies.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has caused the coronavirus diseases 2019 (COVID-19) pandemic, continues to spread rapidly worldwide and is associated with high rates of mortality among older adults, those with comorbidities, and those in poor physiological states. This paper aimed to systematically identify the impact of frailty on overall mortality among older adults with COVID-19. We conducted a systematic review of the literature indexed in 4 databases. A random-effects model with inverse variance-weighted meta-analysis using the odds ratio was used to study the association of frailty levels with clinical outcomes among older adults with COVID-19. Heterogeneity was measured using the I2 statistic and Egger's test. We identified 22 studies that met our inclusion criteria, including 924,520 total patients. Overall, frailty among older adults was associated with high rates of COVID-19-related mortality compared with non-frail older adults (OR [odds ratio]:5.76; 95% confidence interval [95% CI]: 3.85-8.61, I2: 40.5%). Our results show that physical limitations, such as those associated with frailty among older adults, are associated with higher rates of COVID-19-related mortality.