Recommended Needle Sizes, Sites, and Volumes for Injection

+-------+-------------+--------------+---------+---------+----------+
| *     | **Sub       | **Int        | **Int   | *       | **Intrag |
| *Spec | cutaneous** | ramuscular** | raperit | *Intrav | astric** |
| ies** |             |              | oneal** | enous** |          |
+=======+=============+==============+=========+=========+==========+
| Rat   | Scruff,     | Quadrice     | 5-10    | Lateral | 5 ml     |
|       | back,       | ps/posterior | ml,     | tail    |          |
|       |             | thigh, 0.3   |         | vein,   |          |
|       | 5-10 ml,    | ml,          | 23 G or | 0.5 ml, |          |
|       |             |              | smaller | 25 G or |          |
|       | 21 G or     | 23 G or      |         | smaller |          |
|       | smaller     | smaller      |         |         |          |
+-------+-------------+--------------+---------+---------+----------+
| Mouse | Scruff, 2-3 | Quadrice     | 2-3 ml, | Lateral | 0.5 ml   |
|       | ml,         | ps/posterior |         | tail    |          |
|       |             | thigh, 0.05  | 23 G or | vein,   |          |
|       | 21 G or     | ml,          | smaller | 0.5 ml, |          |
|       | smaller     |              |         | 25 G or |          |
|       |             | 25 G or      |         | smaller |          |
|       |             | smaller      |         |         |          |
+-------+-------------+--------------+---------+---------+----------+

*Adapted from Laboratory Animals Anesthesia (P.A. Flecknell, Academic
Press, 1987) and Experimental and Surgical Technique in the Rat --
Second Edition (H.B. Waynforth and P.A. Flecknell, Academic Press,
1992)*

# GENERAL ADMINISTRATION NOTES

-   Recommendations are based on the adult body weight of a rat \[200
    g\] and the adult body weight of a mouse \[20 g\]

-   These volumes should be reduced if the injected material is likely
    to irritate tissues OR if using an

oil-based vehicle for gavaging

-   Changing needles also serves to keep the injection needle from
    becoming dulled if passed through a stoppered vial

-   For IV injections, it is recommended to use the lateral tail vein,
    while the mouse is enclosed within a commercial or custom made
    restrainer. Dilation of the vein is accomplished by warming of the
    tail by immersion in warm water or use of a heat lamp. Five minutes
    of supplemental heat may be necessary for optimal dilation. Monitor
    carefully to prevent the animal from being burned or overheated by
    the heat source. The vein is best entered in the proximal 1/3 of the
    tail, and a successful injection is obvious to the user \[based on
    lack of resistance as the plunger is depressed\]. If repeat
    injections are performed, it is recommended that user start further
    down the tail and to work upwards. In most cases a maximum injection
    volume of 0.5 ml can be safely given to an adult mouse \[based on
    experience and veterinary observations\]. Most users try to limit
    the injection to 0.25 ml \[a standard veterinary recommendation\].
    For cell injections, over-concentration may lead to embolism in lung
    capillaries and death of the recipient. The tendency to clump is
    cell line dependent. Mastering of the injection technique takes
    practice and training sessions may be scheduled by contacting the
    facility manager or the LAM veterinary staff.

-   For hydrodynamic gene therapy, the volumes range from 1.6 to 2.5 ml,
    which is given over 3-5 seconds or 6-8 seconds depending on the
    volume. The standard needle size used for Balb/c mice is 25 gauge
    and for mice with smaller tail veins \[i.e., C57BL/6\] a 27 gauge
    needle is used. Please note that it can take up to 15 seconds to
    administer the agent if a 27 gauge needle is used. Based on
    veterinary observations, the appearance of the mice post-injection
    is strain dependent. The Balb/c mice are not as affected by the
    injections as the B6 mice. The usual clinical manifestation
    post-injection ranges from mild immobility with the lower volume to
    extended periods of immobility with the higher volume. Most often,
    the animals are alert but have a reduced activity level \[stunned
    appearance\]. Severe dyspnea has been reported by others and if seen
    the animals must be humanely euthanized.

-   For routine hydrodynamic-based transfection, anesthesia is not
    recommended prior to the injection due to observed gasping and
    delayed recovery as compared with unanesthetized animals

# GUIDELINES FOR NEEDLE USE

Reuse of needles on multiple animals can lead to dulling of the needle,
increasing the discomfort associated with injections, and can lead to
disease transmission and/or contamination of vials of material to be
injected.  Therefore the ACUC requires justification be provided if the
reuse of needles exceeds the following criteria:

-   A needle may not be used on more than five animals, and must be
    replaced before this point if there is evidence that it is becoming
    dull (e.g., needle is difficult to insert through skin).

-   A needle should only be reused on animals from the same cage to
    avoid transmission of infectious diseases from one cage to the next.

-   A needle, once used on an animal, may not be reintroduced into the
    vial of material being injected unless the vial is to be discarded
    immediately after dosing (avoids the possibility of significant
    bacterial contamination at subsequent use).

From:[
http://www.caninediabetes.org/pdorg/bd_needle.htm](../%20http://www.caninediabetes.org/pdorg/bd_needle.htm)

![](media/image1.jpeg){width="5.99375in" height="3.4298611111111112in"}

From: <http://www.bddiabetes.com/us/main.aspx?cat=1&id=266>

The harm you can cause yourself by reusing a needle is much greater than
any convenience or cost savings. The tips of needles may become damaged
after just one injection. Even though you can't see this damage with the
naked eye, it's still there -- and it may become worse each time you
reuse. There are a lot of good reasons not to reuse syringe or pen
needles:

The tip of a reused needle can be weakened to the point where it breaks
off and gets stuck under your skin.

A reused needle doesn't inject as easily or as cleanly as a new one and
can cause pain, bleeding, and bruising.

Studies have shown that there's a link between needle reuse and the
appearance of lumps of fatty tissue that can form at an injection site
(lipodystrophy).

BD's thin, fine, high quality needles are designed to be used one time
only. These are photographs showing the type of damage that can occur
with needle reuse.\*

![](media/image2.jpeg){width="5.997916666666667in"
height="2.8569444444444443in"}

\*photographs from Dieter Look and Kenneth Strauss study: "Nadeln
mehrfach verwenden?" Diabetes Journal 1998, 10:S. 31-34.