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Divergent genetic selection for wool growth as a single trait has led to major changes in sheep physiology and metabolism, including variations in rumen microbial protein production and uptake of α-amino nitrogen in portal blood. This study was conducted to determine if sheep with different genetic merit for wool growth exhibit distinct rumen bacterial diversity. Eighteen Merino wethers were separated into groups of contrasting genetic merit for clean fleece weight (CFW; low: WG− and high: WG+) and fed a blend of oaten and lucerne chaff diet at two levels of intake (LOI; 1 or 1.5 times maintenance energy requirements) for two seven-week periods in a crossover design. Bacterial diversity in rumen fluid collected by esophageal intubation was characterized using 454 amplicon pyrosequencing of the V3/V4 regions of the 16S rRNA gene. Bacterial diversity estimated by Phylogenetic distance, Chao1 and observed species did not differ significantly with CFW or LOI; however, the Shannon diversity index differed ( P =0.04) between WG+ (7.67) and WG− sheep (8.02). WG+ animals had a higher ( P =0.03) proportion of Bacteroidetes (71.9% vs 66.5%) and a lower ( P =0.04) proportion of Firmicutes (26.6% vs 31.6%) than WG− animals. Twenty-four specific operational taxonomic units (OTUs), belonging to the Firmicutes and Bacteroidetes phyla, were shared among all the samples, whereas specific OTUs varied significantly in presence/abundance ( P <0.05) between wool genotypes and 50 varied ( P <0.05) with LOI. It appears that genetic selection for fleece weight is associated with differences in rumen bacterial diversity that persist across different feeding levels. Moderate correlations between seven continuous traits, such as methane production or microbial protein production, and the presence and abundance of 17 OTUs were found, indicating scope for targeted modification of the microbiome to improve the energetic efficiency of rumen microbial synthesis and reduce the greenhouse gas footprint of ruminants. [ABSTRACT FROM AUTHOR]

Abstract: Parietaria judaica pollen is one of the main sources of allergens in the Mediterranean area. Its allergenic composition has been studied in detail showing the presence of two major allergens (Par j 1 and Par j 2) and two minor allergens belonging to the profilin and calcium binding protein families of allergens (Par j 3 and Par j 4, respectively). Clinical reports support the hypothesis of a limited cross-reactivity between profilin from Parietaria and unrelated sources. We screened a P. judaica cDNA library to identify novel forms of profilins with allergenic activity. This strategy allowed us to isolate a 767bp cDNA containing the information for a 131 amino acids protein with homology to profilins from unrelated sources greater than that observed with the already published Parietaria profilins. This profilin was expressed in Escherichia coli as a recombinant protein and its immunological prevalence was studied in a population of Parietaria allergic patients from Southern Europe. Immunoblotting analysis showed that the Parietaria profilin was recognized by IgE from 6.5% of the allergic population. Finally, a selected population of profilin allergic patients was enrolled to demonstrate the cross-reactivity of this novel variant with other profilins from grass and date palm. In conclusion, molecular cloning and immunological studies have allowed the isolation, expression and immunological characterization of a novel cross-reactive profilin allergen from P. judaica pollen named Par j 3.0201. [Copyright &y& Elsevier]