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OBJECTIVE: This study investigated the effect of fermented biogas residue (FBR) of wheat on the performance, serum biochemical parameters, and meat quality in pigs. METHODS: We selected 128 pigs (the mean initial body weight was 40.24±3.08 kg) and randomly allocated them to 4 groups (1 control group and 3 treatment groups) with 4 replicates per group and 8 pigs per pen in a randomized complete block design based on initial body weight and sex. The control group received a corn-soybean meal-based diet, the treatment group fed diets containing 5%, 10%, and 15% FBR, respectively (abbreviated as FBR5, FBR10, and FBR15, respectively). Every group received equivalent-energy and nitrogen diets. The test lasted 60 days and was divided into early and late stages. Blood and carcass samples were obtained on 60 d. Meat quality was collected from two pigs per pen. RESULTS: During the late stage, the average daily feed intake and average daily gain of the treatment groups was greater than that of the control group (p<0.05). During the entire experiment, the average daily gain of the treatment groups was higher than that of the control group (p<0.05). Fermented biomass residue did not significantly affect serum biochemical parameters or meat quality, but did affect amino acid profiles in pork. The contents of Asp, Arg, Tyr, Phe, Leu, Thr, Ser, Lys, Pro, Ala, essential amino acids, non-essential amino acids, and total amino acids in pork of FBR5 and FBR10 were greater than those of the control group (p<0.05). CONCLUSION: These combined results suggest that feeding FBR could increase the average daily gain and average daily feed intake in pigs and the content of several flavor-promoting amino acids.

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A cellulase gene (cel28a) was isolated from a rumen microbial metagenome library of goat rumen microorganisms, cloned into E. coli, and expressed in active form. The gene has a length of 1596 bp obtained using a genome walking Kit and encodes a protein of 509 amino acids with a calculated MW of 55 kDa. The deduced amino acid sequence was homologous with cellulases belonging to the glycosyl hydrolase family 5 (GH5). The expressed protein showed activity toward carboxymethylcellulose (CMC) and xylan, suggesting non-specific endoglucanase activity. The optimal conditions for endoglucanase and xylanase activities were 50 °C and pH 5.0. The metal ions (Ca(2+), Fe(2+), Mn(2+) and Co(2+)) stimulated the cellulase activity of cel28a, while the other metal ions and chemicals (Ni(2+), Mg(2+), Zn(2+), Cu(2+), SDS and EDTA) inhibited the cellulase activity. Further examination of substrate preference showed a higher activity with CMC, oat spelt xylan and birchwood xylan than with filter paper and microcrystalline cellulose, again suggesting that the protein was an endoglucanase with xylanase activity.

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The neonatal Fc receptor (FcRn) transports IgG from mother to young and is involved in antigen presentation. FcRn is structurally similar to MHC class I, but its intracellular trafficking pathway is much more analogous to that of MHC class II. Ia-associated invariant chain (Ii) molecules play an additional role in directing MHC class II trafficking within the endocytic compartments by physical association with MHC class II. This study addresses the question of whether pig Ii chain plays this important role in FcRn trafficking to the endoplasmic reticulum. Red or green fluorescent protein-fused Ii or FcRn was constructed, and the intracellular localization of pig Ii with FcRn was detected using confocal microscopy. Immunoprecipitation and western blotting were used to test for their association. The results indicate that pig Ii chain specifically interacts with both FcRn H chain alone and FcRn-ß2m complex, and the CLIP in Ii was required for FcRn-Ii association. A truncated FcRn deletion in the cytoplasmic tail changed the intracellular localization of FcRn. However, the truncated FcRn can still combine Ii. This indicated that the cytoplasmic tail of FcRn fails to affect FcRn association with Ii. These results suggest that association of FcRn with Ii chain is relevant, and appreciation of this process is important to the understanding of how IgG is transported.

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OBJECTIVE: To isolate thermophilic bacteria to degrade organic substances of dead-pig. METHODS: Primary screening was done by using diluted plate count and selective medium, and then enzyme activity was measured for secondary screening. Two thermophilic bacterial strains N-3 and Y-3 were isolated, and could degrade protein and lipids. To test their effect, the isolates were mixed (V: V = 1:1, the number of bacteria was 10(8) CFU/mL) and inoculated in dead-pigs and sawdust composting with different doses (0%, 0.3%, 0.6% and 0.9% of the wet weight of fermentation materials). RESULTS: Strain N-3 was identified as Bacillus aestuarii and Y-3 as Geobacillus thermodenitrificans, based on their 16S rDNA gene sequences. The composting temperature of the 0.3%, 0.6% and 0.9% inoculation group could reach 60 degrees C and maintain at the high temperature for about 10 d, which is higher than control (P < 0.01). At the end of composting, the dead-pig degradation rate of the (0%, 0.3%, 0.6% and 0.9% inoculation groups were 71.2%, 75.7%, 96.7% and 97.1%, respectively. The groups of 0.6% and 0.9% were significantly higher than the control (P < 0.01). CONCLUSION: Sufficient amount inoculation of thermophilic bacteria (> 0.6%) could effectively increase composting temperature, maintain thermophilic stage for longer time, and accelerate degradation of dead-pig by composting.

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