Patricia V. Turner

Single nucleotide polymorphisms in mannan-binding lectins and ficolins in various strains of mice

Mannan‐binding lectin (MBL) and ficolin are collagenous lectins produced primarily by the liver and are involved in innate resistance to microbial pathogens. Mice have two MBL genes (Mbl1 and Mbl2) that encode MBL‐A and MBL‐C, respectively. Similarly, the murine Fcna and Fcnb genes encode ficolin‐A and ficolin‐B. Several single nucleotide polymorphisms (SNP) in the human MBL2 gene are responsible for various innate immune dysfunctions due to abnormal structure or expression of human MBL‐C. In these studies, we identified SNPs in the expressed collagenous lectin genes Mbl1, Mbl2, Fcna, and Fcnb in 10 strains of mice designated high priority Group A strains by the Mouse Phenome Project (129S1/SvImJ, A/J, BALB/cByJ, C3H/HeJ, C57BL/6 J, DBA/2 J, FVB/NJ, SJL/J, CAST/EiJ and SPRET/EiJ) by sequencing gene exons by reverse transcription‐polymerase chain reaction (RT‐PCR). Sequence comparisons identified a total of 15 structural SNPs in Mbl1 in two strains, 27 SNPs in Mbl2 in five strains, and 19 and 15 SNPs in Fcna and Fcnb, respectively, in two strains. Two non‐synonymous SNPs were identified in the collagen‐like domain of mouse Fcnb that are similar to the coding polymorphisms in the collagen‐like domain of human MBL2. Most of the non‐synonymous SNPs identified in Mbl1 and Mbl2 occurred in the carbohydrate‐recognition domains (CRDs), and some resulted in altered residues close to known ligand binding sites. Similarly, most non‐synonymous SNPs of Fcna and Fcnb were identified in the fibrinogen‐like CRD. The miscoding SNPs found in the CRD regions of mouse Mbl1, Mbl2, Fcna and Fcnb may be associated with strain differences in glycan binding avidity and disposition of microbial or host ligands. Furthermore, the non‐synonymous mutations in the collagen‐like domain of Fcnb may alter the structure of the mature ficolin‐B protein leading to functional deficiencies. These differences may be important in the pathogenesis of susceptibility differences between inbred strains to various infectious microorganisms.

On-farm biosecurity practices and causes of preweaning mortality in Canadian commercial mink kits

BackgroundMink are an important animal commodity group in Canada and excessive kit mortality represents a significant loss to production. National biosecurity standards have been developed for Canadian mink farms, but it is unclear how well these standards have been implemented as there are no studies correlating management practices of mink producers with causes of death in mink kits. To that end, we surveyed Ontario mink producers on their biosecurity and management practices and conducted almost 5660 post mortem examinations on found-dead, preweaned kits to characterize mink farm biosecurity practices and causes of death in preweaned kits.ResultsWe found that very few biosecurity and management practices were uniformly used by producers, despite good awareness of appropriate practices. Use of personal protective equipment was implemented by fewer than 50% of respondents, while control of mink shed access, disinfection of feed containers after use, and use of a rodent control program were the only practices implemented by greater than 70% of respondents. Only 18% of producers reported regular use of antimicrobials in feed or water, although 91% stated they used antimicrobials for treatment of bacterial diseases on a regular basis. On post mortem examination, no gross abnormalities were noted in 71% of the kits, 45% were thought to be stillborn or aborted, 27% had some form of abnormal fluid distribution in the body, and 2% had a congenital malformation. A subset of 69 gastrointestinal tract samples was submitted for bacterial culture, of which 45 samples yielded sufficient growth. Most interesting was the identification of Salmonella enterica serovar Heidelberg in 11% of samples.ConclusionsThe results of this study will provide a benchmark for Canadian mink producers and their veterinarians, defining the areas to which greater attention should be given to ensure more rigorous biosecurity practices are in place. Ultimately, these improvements in practices may contribute to increased mink production and animal well-being.

Animal Environments and Their Impact on Laboratory Animal Welfare

The impact on welfare of the numerous characteristics of the living environment of a laboratory animal has received increasing attention in recent years. The standard research animal housing design of a box (the cage), within a bigger box (the animal room), within an even bigger box (the animal facility), has undergone transformation at many institutions, with the result that animals are often afforded more vertical space, access to the outdoors, windows to the outside, and many other design features (depending upon the species) that break from tradition. The living environment is typically considered to be comprised of physical, chemical, and biological factors that may have synergistic or competing effects on the welfare of an animal. Other less tangible aspects, such as enclosure space, social complexity, and the human factor play a critical role in laboratory animal welfare but pose special challenges to interpret their precise effects in the milieu of other environmental features. As efforts to optimize laboratory animal welfare through improved living environments, exemplified by the expanding emphasis on social housing and other forms of environmental enrichment, gain momentum in the industry, innovation and new technologies balanced with safety considerations for the animal and the personnel, animal management (e.g. animal observation, access to the animal), and the research objectives predominate. This chapter delineates key factors in the living environment that impact animal welfare with a view to highlighting areas that are well understood in terms of the impact on welfare and those that necessitate further research and more creativity.

Rodent and Rabbit Welfare in the Research Environment

This chapter will explore considerations for ensuring good welfare of research rabbits and rodents, emphasizing mice, rats, and guinea pigs. This includes assessing welfare in these species; selected housing and husbandry requirements; welfare issues associated with breeding, procurement, and transportation; veterinary care; perioperative care; experimental endpoint determination; and euthanasia. Our understanding of rabbit and rodent welfare continues to evolve as new information and technology become available.