• Mouse and rat models are packed in their barrier unit of origin or laminar flow hoods and shipped in sterilized Taconic Transit Cages™ (TTC™) with a food and hydration source. Dividers are available for purchase and can be used to easily divide the TTC™ into 2, 3, or 4 compartments. Learn more.
• Germ-free mice are packed in special germ-free shippers.

At Taconic, the maximum density per cage is set using The Guide for Care and Use of Laboratory Animals and guidelines from our Animal Quality team. Densities are reduced with the age of the animals as well as through order fulfillment and attrition. Taconic recommends following our standard packing densities as these are optimized for animal welfare and specific for our transport containers. Changes to animal density (even lowering while maintaining cagemates) can trigger aggression. It is best for the animals for customers to lower animal density at unpacking or ideally, after the acclimation period, rather than prior to transport, adding appropriate enrichment to the cages. If a customer requires changes to Taconic standard density and shipping conditions, the customer must accept the risk of increased aggression and may forfeit any compensation for aggression during or after transport. Taconic will attempt to meet the custom request, however if insufficient animals are available in individual holding cages, but the full quantity exists for the age range requested, Taconic will pack as cagemates/full cages per section. The number per section is not guaranteed.

• Week of birth and source barrier unit identification are provided on shipping labels. For exact “date of birth” requests on Traditional Models, place orders prior to the needed birth date
• Week of birth (Date of birth +/- 3 days): No Charge
• Exact date of birth: $6.87/€9.16 per animal for Murine Pathogen Free™ traditional models. Please inquire for pricing for other models or health designations. Lead time is required.
• Taconic may combine animals from different weeks of birth in a single Taconic Transit Cage unless otherwise requested at time of order. Additional fees may apply for packing animals by week of birth.

• Mice and rats can lose up to 10% of their body weight in transit, however after 48 hours acclimation most models can be expected to regain any weight lost in shipment.
• Taconic will select animals within a typical weight range for its corresponding age at no additional charge. Weight charts are provided as a guide.
• All weights are weights at the time of packing.
• Orders for specific weight spans take additional time to select and pack and as such will be assessed a fee of $3.37/€3.43 per animal.
• Mice can be ordered with a minimum 3 gram span (i.e 10-13 grams) and rats with a minimum 15 gram span (i.e. 200-215 grams).
• Taconic cannot accommodate orders for cagemates with a weight specification.

Taconic will select animals from a production location based on availability and to best utilize the animals produced. Location-specific requests result in less efficient use of available inventory and thus greater animal obsolescence (waste) and increased production costs. Taconic is committed to the 3Rs, and we encourage customers to allow Taconic to select the source location of requested animals in order to reduce animal obsolescence. Location-specific sourcing requests will be assessed a fee of $3.37/€3.43 per animal.

• Orders for retired breeders are filled from live breeding colonies. As such, female retired breeders may be pregnant at time of shipment.
• Taconic may be able to fill requests for guaranteed non-pregnant retired breeders; this would be at a higher price than the posted retired breeder price.
• Retired breeders will vary in age and are sourced both from older animals at the end of their scheduled breeding time as well as younger breeders which are non-productive. It is not possible to request retired breeders of a specific age. Information on the specific week of birth is not available for retired breeders, but upon request, information on the month of birth can be provided at time of shipping.

Taconic offers female breeders with litters for some lines. Pups must be at least 7 days old at time of shipping. Female with litter orders are filled using lactating females from active production colonies, and most models are harem bred. Lactating females may be pregnant at time of shipping. In most cases, the litter is selected and shipped with a female breeder from the same harem breeding cage as the litter. Lactating female is not necessarily the biological mother for that litter. In some cases, litters are selected and shipped with a lactating female from another breeding cage. Requests for lactating females with litters using the biological mother cannot be accommodated for all orders or models. If biological mother is required as a special request, this may limit the accompanying litter size and require an additional fee.

Taconic's breeding specialists use proven, highly effective procedures to generate timed pregnant mice and rats. While gestational age cannot be determined with total precision, strict adherence to pre-defined mating procedures, and close monitoring of female mice and rats after they are co-housed with males, can accurately define the 24-hour period during which mating, and presumably, conception occurs.

Procedures

• At Taconic, the day of sperm cell detection in females is called the sperm-positive date and is considered Day 1 of gestation.
• After co-housing females with males the prior day, Taconic technicians take vaginal swabs of females between 7 and 10 a.m. daily or do plug checks, depending on the model to confirm that mating has occurred. This procedure assumes that timed-pregnant females have mated and conception has occurred from 0 to 24 hours before the designated sperm-positive date.
• Presumably, the majority of matings occur around the midpoint of the previous day's dark cycle, from 6 P.M. to 6 A.M.
• When investigators order timed-pregnant animals at a specified developmental age for delivery on a specific date, Taconic technicians select animals based on the sperm-positive date. For instance, for an order for rats bearing embryos at Day 15 of gestational age for delivery on January 15, Taconic would select timed-pregnant females with a sperm-positive date of January 1.
• Since Taconic's method for selecting timed-pregnant females results in full-term pregnancies with a high success rate as evidenced by the chart below, extra mice and rats are not supplied with each order. However, spontaneous abortions and small litters do occur on occasion. In addition, animals under 14 days do not allow for a visual confirmation of pregnancy and cannot be palpated to confirm pregnancy. When expending considerable time and resources to prepare for a study using timed-pregnant mice or rats on a specific day, and especially when requiring a specific number of pups to be born on a particular day or using a small number of dams or fetuses, please be sure to order additional animals. Please see the chart below to assist in determining the appropriate number of animals to order for your study.

Tips for Ordering

• Specify the sperm-positive date when ordering timed pregnant models.
• Taconic advises customers to order extra timed pregnant animals to prevent any potential issues.

Pregnant Animal Recommendations and Policies

• Taconic's Timed Pregnant Sprague Dawley® rats exhibit greater than 95% accuracy for timing of gestational age. Taconic recommends orders for pregnant mice be less than 18 days gestation, and orders for pregnant rats be less than 19 days in order to prevent the animals from delivering in transit.
  
  

   

  Model Type	Under 14 days Gestation	14+ days Gestation
  SD Rats	95%	100%
  Outbred Mice	75%	100%
  Inbred Mice	60%	75%

   

• If problems regarding gestational age or pregnancy with timed pregnant orders, customers should immediately contact Taconic's Customer Service Department to provide information regarding the number of animals involved and how non-pregnancy or mistiming was determined. Whenever possible, necropsy information and pictures should be provided to assist complaint investigations for a root cause. Taconic will issue the appropriate credit based on our investigation.
• All untimed pregnant orders are filled using visibly pregnant females selected from Production Colony breeders. Customers should be aware that untimed pregnant mice and rats may deliver their litters while in transit and that no assurances are given regarding the size of the litter.

Occasionally, we have delays outside of our control that may impact animal delivery. Items such as severe weather conditions (heat or cold) and limited flight availability related to global airline staffing shortages, may disrupt ground and air transportation. In those cases, a dedicated support team member will proactively reach out to you to share any updates on the status of your shipment.