Intraoperative cryoanalgesia on reducing post-tonsillectomy pain scales: a meta-analysis of randomized controlled trials.

OBJECTIVE: To assess the effect of intraoperative cryoanalgesia on subjective pain scores of patients after tonsillectomy. METHODS: A systematic review of PubMED, Web of Science, EMBASE was performed using the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) standards. For the first time, we included and quantitative synthesized English-language randomized controlled trials (RCT) evaluating patients of all age groups with benign pathology who underwent tonsillectomy with intraoperative cryoanalgesia versus without. RESULTS: A total of 835 publications were identified, and 7 articles with 463 participants met our criteria were selected for meta-analysis. The standard mean difference for overall subjective pain score, subjective pain scores at postoperation Day1 (POD1), POD7 were -1.44 with 95% confidence interval (CI) [-2.17, -0.72], P = .0001; -1.20 with 95% CI [-1.89, -0.50], P = .0007; -0.90 with 95% CI [-1.46, -0.35], P = .001 respectively, both in favor of cryoanalgesia. Nevertheless, subgroup analysis by surgical technique showed no robust effect between hot technique and "relative" hot technique on overall pain: (-1.72, 95% CI [-2.71, -0.73]) vs. (-1.06, 95% CI [-2.20, 0.07]), p=.39; on POD1: (-1.56, 95% CI [-2.78, -0.33]) vs. (-0.97, 95% CI [-1.83, -0.11]), p=.39; and on POD7 (-1.11, 95% CI [-1.81, -0.40]) vs. (-0.89, 95% CI [-2.02, 0.25]), p=.13. The standard mean difference for postoperative secondary bleeding rate was 1.29 with 95% CI 0.37,4.52], p = .06, no difference in 2 groups. CONCLUSION: Limited evidence suggests that intraoperative cryoanalgesia during tonsillectomy leads to lower subjective pain score on overall, POD1 and POD7 without differences on post-operation bleeding rate.

Foraging selectivity of co-grazing cattle and sheep varies differently with plant diversity.

Foraging selectivity by domestic herbivores is a critical factor affecting plant community structure and functioning of rangeland. However, there is rather limited knowledge of whether and how foraging selectivity of different herbivore species varies with plant diversity. Here, we experimentally investigated the foraging selectivity of co-grazing cattle and sheep across 15 plots with varying plant diversity gradients in a meadow steppe. The results showed that the foraging selectivity of sheep significantly increased with increased plant diversity, while that of cattle did not change. This effect was still present after accounting for the effect of plant community protein. Increased plant diversity also resulted in more traveling steps for sheep, but had no effect on cattle. Further, the foraging selectivity of sheep was stronger than that of cattle at higher plant diversity levels, but weaker at lower diversity levels. Our results indicate that sheep and cattle can have completely different impacts on grassland plant communities and dynamics, depending on the context of plant diversity, due to their distinct and varying foraging selectivity. Sheep behave more sensitively to changes in plant diversity. We thus suggest that sheep should be used with caution on grasslands with high plant diversity due to strong diet selectivity. Instead, cattle, with stable behaviors, should be a relatively conservative management tool to conserve plant diversity.

Livestock grazing modifies soil nematode body size structure in mosaic grassland habitats.

Body size is closely related to the trophic level and abundance of soil fauna, particularly nematodes. Therefore, size-based analyses are increasingly prominent in unveiling soil food web structure and its responses to anthropogenic disturbances, such as livestock grazing. Yet, little is known about the effects of different livestock on the body size structure of soil nematodes, especially in grasslands characterized by local habitat heterogeneity. A four-year field grazing experiment from 2017 to 2020 was conducted in a meadow steppe characterized by typical mosaics of degraded hypersaline patches and undegraded hyposaline patches to assess the impacts of cattle and sheep grazing on the body size structure of soil nematodes within and across trophic groups. Without grazing, the hypersaline patches harbored higher abundance of large-bodied nematodes in the community compared to the hyposaline patches. Livestock grazing decreased large-bodied nematodes within and across trophic groups mainly by reducing soil microbial biomass in the hypersaline patches, with sheep grazing resulting in more substantial reductions compared to cattle grazing. The reduction in large-bodied nematode individuals correspondingly resulted in decreases in nematode community-weighted mean (CWM) body size, nematode biomass, and size spectra slopes. However, both cattle and sheep grazing had minimal impacts on the CWM body size and size spectra of total nematodes in the hyposaline patches. Our findings suggest that livestock grazing, especially sheep grazing, has the potential to simplify soil food webs by reducing large-bodied nematodes in degraded habitats, which may aggravate soil degradation by weakening the bioturbation activities of soil fauna. In light of the widespread land use of grasslands by herbivores of various species and the ongoing global grassland degradation of mosaic patches, the recognition of the trends revealed by our findings is critical for developing appropriate strategies for grassland grazing management.

Experimental impacts of grazing on grassland biodiversity and function are explained by aridity.

Grazing by domestic herbivores is the most widespread land use on the planet, and also a major global change driver in grasslands. Yet, experimental evidence on the long-term impacts of livestock grazing on biodiversity and function is largely lacking. Here, we report results from a network of 10 experimental sites from paired grazed and ungrazed grasslands across an aridity gradient, including some of the largest remaining native grasslands on the planet. We show that aridity partly explains the responses of biodiversity and multifunctionality to long-term livestock grazing. Grazing greatly reduced biodiversity and multifunctionality in steppes with higher aridity, while had no effects in steppes with relatively lower aridity. Moreover, we found that long-term grazing further changed the capacity of above- and below-ground biodiversity to explain multifunctionality. Thus, while plant diversity was positively correlated with multifunctionality across grasslands with excluded livestock, soil biodiversity was positively correlated with multifunctionality across grazed grasslands. Together, our cross-site experiment reveals that the impacts of long-term grazing on biodiversity and function depend on aridity levels, with the more arid sites experiencing more negative impacts on biodiversity and ecosystem multifunctionality. We also highlight the fundamental importance of conserving soil biodiversity for protecting multifunctionality in widespread grazed grasslands.