The Ohio State University (OSU) requests funding to purchase animal care equipment to enhance the conduct of biomedical research as well as increase regulatory compliance while optimizing animal welfare. Specifically, we are requesting $499,133 to purchase 18 Lab Products Super Rat MicroIsolator(r) 40 IVC racks with auto water, HEPA-filtered air supply units, complete cages with filter tops, and an additional 50% complete cages to provide sufficient supplies for routine cage changes. This project is intended to equip rodent housing rooms within an existing vivarium which already possesses the necessary plumbing and auto water, electrical, HVAC, cage wash, etc. capabilities without requiring any additional renovations, alterations, or fixed equipment. OSU is committed to upholding the NIH expectation regarding appropriate housing space while also accounting for the animals' social needs. It was noted on our most recent Association and Accreditation of Laboratory Animal Care International (AAALAC, Int.) site visit and the last two semi-annual Institutional Animal Care and Use inspection reports that large rats were individually housed at our facility. The recommended minimum space for rats in The Guide for the Care and Use of Laboratory Animals requires increased floor space with respect to animal size. However, our current rat caging requires that mature rats be housed individually to maintain compliance with Guide standards. The requested equipment will allow for increased floor space per cage, resulting in the ability to provide social housing of rats regardless of size. This is essential not only in ters of animal welfare, but also significantly impacts biomedical research support at our institution as it has been demonstrated that failure to meet animals' needs may result in abnormal brain development, physiologic dysfunction, and behavioral disorders. The requested equipment will benefit all investigators utilizing rat models at OSU. There are currently 59 researchers housing rats that have generated grants providing over $12,338,000 in direct research funding encompassing, but not limited to, cardiovascular, metabolic, fetal development, behavioral, and neurophysiological disciplines of study. The age and condition of current equipment in conjunction with the inability to provide optimal social housing due to size limitations to maintai regulatory compliance necessitates the need for this request. This proposal is also needed due to the inability to utilize capital expenditures for equipment purchases. This project is significat in addressing the strategic needs of our animal research community while aligning OSU's commitment to excellence in animal welfare.