0 ��g of natural hLZ standard (Sigma-Aldrich) as a positive control. Transparent zones around filters containing the natural hLZ standard or milk from transgenic pigs were clearly visible from the culture medium after incubation for 24 h (Figure 2B). No transparent zone was formed by milk samples from the non-transgenic pig. By measuring the diameter of the clear zone, rhLZ activity Axitinib cancer from transgenic pigs was much lower than the activity of 1 ��g of the natural hLZ standard, which was consistent with the western blotting and ELISA results. To quantify rhLZ activity, milk samples collected from five transgenic pigs and four non-transgenic pigs were examined using the turbidimetric assay. The average rhLZ activity during the lactation period was 92,272��26,413 U/mL.

The highest average activity was 110,076��28,238 U/mL on day 14 (Figure 2C and Table S2 in File S1). The general trend of average rhLZ concentration and activity during the lactation period was quite consistent. Since the turbidimetric assay can not distinguish between endogenous pig lysozyme and rhLZ, we detect the enzymatic activity of milk with three times dilution collected from four non-transgenic lactating sows. The non-transgenic milk collected at 6, 12 and 24 h showed little enzymatic activity, the average value were 84.65��6.66 U/mL, 69.59��11.40 U/mL and 3.65��0.42 U/mL, respectively. But we can not detect any enzymatic activity of milk collected after 48 h (Table S3 in File S1).

Raw Milk Component in Samples from First-parity Controls and Transgenic Gilts Analysis of fat, protein, and lactose content as well as concentrations of 16 different amino acids showed no significant differences in milk samples from first-parity non-transgenic controls and transgenic gilts (Tables 2 and S4 in File S1). Table 2 Raw components of transgenic milk compared to conventional milk. Weight and Growth of Piglets To determine whether the presence of the human lysozyme transgene in first-lactation gilts influenced litter growth and health, we divided 40 piglets into two feeding groups nursing from four transgenic and four non-transgenic gilts separately and weighted them every 2 days from the third day after farrowing. There was no significant difference between the average mass of piglets nursed by transgenic and non-transgenic sows on days 3 and 21 (Table 3). Table 3 Body weight of two piglet groups on neonatal days 3 and 21.

The rhLZ Milk Reduced the Number of E. coli in the Duodenum of Piglets in the Feeding Experiment All piglets were slaughtered at 22 days of age and their intestinal contents were collected for microbial analysis using a culture-based bacterial assessment method. Six Anacetrapib types of bacteria were selected for culturing: total aerobes, total anaerobes, Salmonella spp., E. coli, Bifidobacterium spp., and Lactobacillus spp. The results showed that number of E. coli in the duodenum of the experimental group was significantly decreased (p<0.