Vitamin D3 and 25-hydroxyvitamin D3 in pork and their relationship to vitamin D status in pigs

The content of vitamin D in pork produced in conventional systems depends on the vitamin D concentration in the pig feed. Both vitamin D(3) and 25-hydroxyvitamin D(3) (25(OH)D(3)) are essential sources of dietary vitamin D; however, bioavailability assessed by serum 25(OH)D(3) concentration is reported to be different between the two sources. Furthermore, the relationship between serum 25(OH)D(3) level and the tissue content of vitamin D(3) and 25(OH)D(3) is unknown. The objective of this study was to investigate the potential of increasing the content of vitamin D in different pig tissues by increasing the levels of vitamin D(3) and 25(OH)D(3) in the pig feed for 49 d before slaughter. Concurrently, the 25(OH)D(3) level in serum was investigated as a biomarker to assess the content of vitamin D(3) and 25(OH)D(3) in pig tissues. Adipose tissue, white and red muscle, the liver and serum were sampled from pigs fed feed containing either vitamin D(3) or 25(OH)D(3) at 5, 20, 35 or 50 µg/kg feed for 7 weeks before slaughter. The tissue 25(OH)D(3) level was significantly higher in the pigs fed 25(OH)D(3) compared with those fed vitamin D(3), while the tissue vitamin D(3) level was higher in the pigs fed vitamin D(3) compared with those fed 25(OH)D(3). The content of 25(OH)D(3) in the different tissues fully correlated with the serum 25(OH)D(3) level, whereas the correlation between the tissue content of vitamin D(3) and serum 25(OH)D(3) was dependent on the source of the ingested vitamin D(3)

Factors associated with usage of antimicrobials in commercial mink (Neovison vison) production in Denmark

AbstractThe American mink (Neovison vison) is used for commercial fur production in Denmark. In recent years, antimicrobial prescription for Danish mink has been increasing. In this study, the patterns and trends in antimicrobial use in mink were described and a multi-variable variance analysis was carried out with the objective of identifying risk factors for antimicrobial use on herd level. The study was based on register data for 2007–2012. Information on antimicrobial use was obtained from the national database VetStat, monitoring all medicinal products used for animals on prescription level. Data on microbiological feed quality was obtained from the Voluntary Feed Control under the Mink producers Organization, and data on herd size and the relation between farm and feed producer was obtained from the registers at Kopenhagen Fur, based on yearly reporting from the mink producers. Descriptive analysis showed a clear significant effect of season on antimicrobial use, with a peak in “treatment proportions”, TP (defined daily doses per kg biomass-days) in May, around the time of whelping, and a high level in the following months. In autumn, a minor peak in antimicrobial use occurred throughout the study period. From 2007 to 2011, a 102% increase in annual antimicrobial TP was noted; on herd level, the increase was associated with an increasing frequency of prescription, and a decrease in the amounts prescribed in months with prescription. A binomial model showed that on herd level, the annual number of months with antimicrobial prescription was significantly (p<0.01) affected by feed producer, veterinarian, disease (specific laboratory diagnosis) infection, herd size and year, with an interaction between feed producer and year. A log-normal model showed that in months with antimicrobial use, the TP on herd level was significantly (p<0.001) affected by year, month (season), feed producer, feed quality score, veterinarian, herd size and laboratory confirmed diagnosis of specific infections; additionally the interaction terms year×feed producer and herd size×month were significant (p<0.001).In conclusion, antimicrobial use on herd level was significantly associated with the microbiological food quality, the feed producer, and the veterinarian. The prescription patterns varied significantly between veterinarians, and some veterinarians were associated with both larger and more frequent prescriptions of antimicrobials at herd level. Herd size is associated with different prescription patterns. Finally, infection with Pseudomonas aeruginosa, astrovirus, influenza virus and Salmonella spp. was associated with an increase in antimicrobial use