Questions related to Rat Handling
I have had a few lively discussions with colleagues on the appropriate application of the following terms, as they relate to the use of laboratory rats and mice: habituation, acclimation, adaptation, and acclimatization.
When the rats are brought into my research lab, in order to "get used to" everything from the transport from the animal care facility, sounds, sights, odors, etc., is this called habituation?
Preclinical researchers are "on notice" to improve the reproducibility and validity of our data, with the ultimate goal of translatability to clinical discoveries. How can this be accomplished if we cannot even agree on terminology?
I'm currently testing ketamine as an anti-depressant in female ovariectomized rats. Am curious what size field would be ideal to test the effects of ketamine 24h or 1 week after administration.
Recently, my RA and graduate student performed facial vein (sub-mandibular) bleeding in immunized mice (both BALB/c and A.J), several mice died after bleeding. We have changed from lancet to needle but still have mice died after bleeding. The confusing thing was, for several mice, only a tiny amount of blood was obtained so it was impossible due to blood loss. Anyone has the similar experiences so could give us some advice or explanation for the cause of death?
I am trying to administer a hormone daily to a rat for up to 6 months without causing the rats any unneeded stress.
My current options:
- Daily subcutaneous injections.
- Implanted osmotic pumps.
- Daily force feed using gavage.
- Daily syringe feeding .
- Some type of treat containing hormone??? (please let me know if you know of something like this)
Essentially aside from some form of a treat containing the hormone I am not a fan of the 4 other options.
Daily injections would be time consuming for a large sample, and would be inherently stressful to the rats.
Osmotic pumps would require routine changing over the course of the experiment, meaning that the rats would be going into minor surgery every 2-3 weeks.
Daily force feed would be inherently stressful on the rats, and according to the literature on using gavage, can cause throat ruptures, and becoming increasingly difficult over time.
Syringe feeding is the most viable option of all those aside from feeding them some form of capsule or pellet containing the hormone, but would still be quite time consuming to do daily.
Any recommendations or advice on how to proceed here is very welcome. Please help.
I am looking to model different ages (in humans) using a rat model. Does anyone have any papers which describe the developmental markers in brains of rats and humans?
Example) How many months old would a rat have to be to reflect the development of a 12 year old brain in humans?
Currently iam working on preclinical drug interaction studies.
Can anybody suggest the criteria of blood with drawal intervals in rats for drug interaction studies. Many literature showing withdrawing of blood at 0,1,2,4,6,8 and 12 hours interval through retroorbital pluxes. Is it possible to with draw with these intervals from retroorbital pluxes in rats. Please provide your valuable suggestions. Thanking you
I am performing a neuropharmacological study on mice which involves namely Open field test, Hole cross test (HCT), Thiopental sodium-induced sleeping time test, Elevated plus-maze (EPM test)
We recently got an IACUC protocol for tail vein administration. I am currently the only person at the company with prior experience in animal studies. I have been trained in injection/bleeding techniques. However, it is been several years since I have performed tail vein injections. My previous experience was with albino mice where the veins were easily located. Does anyone have a recommendation for a dye that could be used on easily identify if the vein was hit. I believe I have heard of using Evan's blue or food coloring but wanted to get opinions. I know I will have to dilate the veins using heat, and will require lots of practice.
Currently we planned a new project which is involving few surgical techniques. Steriotaxic sugery in mice and introducing alzet pump to mice brains as well.
I've seen different versions of the device:
1. David Kopf Instruments and
2. Animal Stereotaxic Instrument Stereotaxic Instrument with Atlas Integration in Computer
What do you think, which device might be easier to handle with high level of correct injection of the target sol. into the ventricular system and the hippocampus as well.
Do you know if there is any European Institute that give a detailed course and a certificate for that as well?
I'm fine-tuning icv injection technique in mice, but I'm experiencing some problems with anesthesia. From what I've read, many authors use isoflurane. Still, I am interested in finding a long-lasting anesthetic (or a mixture) that can be administered ip, and that further allows the total recovery of the animal.
Could anyone shed new light on?
Thank you very much!
Hello, I want to induce DT2 in rats. I read a lot of articles on this subject and I understood that the dosage of STZ and the time between STZ and NA administration is very important; In almost all articles that I read I found that the proper dose of NA is between 90-140 mg/kg. Masiello P. (1998) who developed this model has used 230 mg/kg NA. What is the reason for such a large difference in dosages between the two? PS: STZ dosage is similar in all cases 40-65 mg/kg" Thank you very much
How much dextrose should I use if I need to induce high-blood sugar in mice for a diabetes study? What dosage/concentration and kind are suggested? Also, should the mice be kept "plugged" into the dextrose source at all times?
I need to feed the rat with powder high fat diet. We used to mix the powder high fat diet with coconut oil and make the powder diet into small balls. But, the rats are not eating these balls properly as compare with pellet. Is there any simple method for intragastric administration of powdered materials to rats?
Thanking you in advance for your valuable suggestions.
I am trying to design a high fat diet for SD rats for a hyperlipidemia study. Please suggest me whether Pork Lard fat directly obtained from the store be directly used along with a modified Chow diet powdered for this study. Or should it be rendered. Also please someone provide me any acceptable nutritional value for the pork unrendered lard.
I've noticed that in some maternal separation papers, it is specified whether rat pups are cross fostered at birth, while in others it is not mentioned. Is cross fostering important when examining early life stressors in later life behaviours? If it is, can anyone provide me with some tips for successful cross-fostering?
Please someone help me out with the per day calorie consumption for Male, Sprague dawley rats. It would be really helpful if any particular equation on calorie requirement could be shared by someone.
Any advice, tips and tricks on how to best perform the surgery and how to set up this model would be greately appreciated.
Were doing experiments with rats (Long-Evans) where we anesthesize them with Urethane and then make a craniotomy. Today it happened that the rat suddenly 'blowed-up' (its back rose and it lookes like his lungs filled completely with air), stiffened and died within a couple of minutes. Does anyone know how this could have happened?
We did not encounter this with the other rats we used, neither does anyone in the institute have a good explanation for this.
Thanks in advance,
After almost a month of Chronic Unpredictable Mild Stress (CUMS), both of my control rats (no stress) and stress-model rats exhibit low serum corticosterone concentration. Surprisingly, the level of ACTH in stress-model rats were significantly higher compared to control rats. Is it a common observation? Because most CUMS literature i found report high corticosterone level in their stressed rats.
I am training some rats on a simple discrimination task, but 4/10 animals are spending up to 40 seconds at the hopper after receiving a reinforcer, licking and occassionally biting. Their weight is a little high but not excessive. What could be the cause?
I was wondering if there are any experimental differences when applying treatment or constructing models (mania model specifically) using these different strains. Of course all strains differs in their behavior and response to treatments but I am looking here for significant variations and whether there are experiments that are done on one strain that is better than the other.
Thanks a lot
I know that physiological changes occur in the brain parenchyma following cannulation and probe insertion that could affect quality of both neurotransmitter or metabolite recovery or delivery. The maximum amount of time I have seen in the literature was 30 days in the pineal gland in a microdialysis study. Accessory question: would you suggest I run any control tests during the microdialysis experiments to ensure microdialysis is optimally performed? Obviously, aside from measuring the concentration of molecule of interest and preferably without having to sacrifice any rats in the midst of the experiment.
Im trying to research with enriched environment conditions, and i want to know if someone knows if its any standarized protocol about it.
I have 2mM stock solution of a compound dissolved in DMSO and I have to give a final dose of 0.5mM to rats weighing 200 gram for my invivo study. How it will be calculated? one of my senior is saying that the final working volume will be the total blood volume of the animal. Please guide me.
What is the normal range of adiponectin in rat sera in ng/ml and to what value it will increase in different diseases cases as its estimation has specific linearity and if the method is specific to special concentration is there a need to estimate its concentration in each group separately using specific dilution
Thanks for consideration
I have been using 600 ul ketamine and 300 ul xylasine for 350 gr male wistar rats. But recently, they have not been going into anesthesia. I tried different doses, opened new medicines and whenever I give them anesthesia I handle them gently, let them to habituate to me and to room. After injection I keep rats in a quiet room preventing bright light exposure. However, it tooks nearly 4- 5 hours for them to go into deep anesthesia. What could be possible causes for this outcome? Thank you already. Have a nice day.
the protocol with the autosampler is straightforward, but the problem we are facing: is how to do the OGTT in the dark cycle without stressing the rats with the oral gavage to push down the glucose down the rat's throat? it takes away all the advantage of having the stress free set up of the autosampler. any suggestions?
Immediately after injection there is mobility impairment stretching and waist pinching. This reaction lasts for about 45 seconds and then the animal regains normal posture and behaviour.
Dosage is 500mg/kg/bw single Ip
95% Pure hydroxyurea in DDH2O
we have IVC system in our department, but facing the difficulty in handling rats and maintenance, as it can accommodate only 2 rats per cage. please anwser this question so that if not necessary we can buy normal rat cages where 5 rats/cage can be kept. it inturn help to reduce the work load.
I need to collect 700 micro-liters of blood from anesthetized rat. I tried to collect from ventral tail artery. But, I was not successful. Please give me tips to know about better choice of blood collection from unanesthetized rat.
Thanking you in advance for your kind replies.
I've been reading articles, but none of them explains how the cage was tilted, only how much they were tilted (30 or 45 degrees). Should I put one of the smaller sides of the cage up or one of the bigger sides? The animals are housed individually in each cage.
I implanted multichannel electrodes in rat and wants to visualize the configuration of Implanted electrode. If I do slicing of the brain, I have to explant the electrode moreover the shape (configuration of the electrode will not visualised).
I am in need of normal reference values (like we have for humans,) for various biochemical parameters in adult male albino wistar rats, like serum glucose,plasma insulin, HbA1C, SGOT, SGPT, ALP,UREA, CREATININE, ALBUMIN, LDL, HDL,TOTAL CHOLESTEROL,TRIGLYCERIDES, VLDL and in vivo liver antioxidant enzymes like SOD,CAT,GPX ,LPO. Please provide me the values with proper references. thanks.
I have to measure the length, weight of the rat puppies few days later immediately after birth. Any idea how to do that?
I also have to collect the liver, brain, adipose tissue and lungs from the pups immediately after the birth.
Can anybody have any idea how to do that. I read some papers but there is no description of the detail protocol. I need some papers/protocols for that.
I have recently started experimenting with establishing rat E18 hippocampal cultures. I have had mixed successes and failures and have learned a great deal along the way. One issue that I have noticed is that when I plate my neurons at densities higher than about 40K/12mm coverslip they are forming non-adherent clumps. I don't mind the sparsity with a lower seeding number, however I would like to culture them to DIV21 and they seem to become less healthy after about two weeks at this density. Does anyone have any advice regarding improving plating density to avoid clumping?
I don't feel that it is a substrate issue because I do get nice adherence, just a little too sparse for my needs. I am culturing in standard supplemented Neurobasal on slips coated with PDL/laminin.
If we want to demonstrate the experiments on isolated rat ileum or any other isolated tissue, then do anybody have better alternate of this without dissecting a rat?
If any software is available for same then can anybody inform me about reliable software which describes & demonstrate all such experiments (pD2, pA2, identification of unknown drug or Bioassay of drug)?
These 2 species look very similar. Charles rives states originated by Drs. Long and Evans in 1915 by crossing several Wistar Institute white females with a wild gray male. To Charles River from Canadian Breeding Farm and Laboratories in 1978.
These rats have taken their name from the Lister Institute, where the stock first originated. From Glaxo to Charles River Laboratories UK in 1990 and again in 1996. To Charles River Germany in 2007.
Has anyone ever compared the behavior?
I want to use one extract, but have no idea which solvent (saline, methanol, ethanol) will be better to use and which route of administration have to select in rats.
Actually, I want to know which method should be used to collect blood from rats because the jugular vein has to be exposed to collect blood which make rat experience a small trauma and additionally there may be a chance of getting infection on that exposed site.
Alternatively retro orbital is very very painful for rats.
I always end up poking the brain to get rid of the vessels and butcher the surface.
This is proving to be too difficult. Any help would be appreciated.
I am having trouble finding a drug that crosses BBB and could possibly help to cure AD induced cognitive impairment in a rat model.
I am interested in doing some directed energy (RF, Wifi, bluetooth, multi-spectrum RF)-associated experiments with rat animal models, (no pharmacological studies involved). Can anyone provide some comments or suggestions on the models I should be using in my protocol? (ICR-wistar hans, Sprague Dawley, B6 inbred/outbred, age, sex, etc.) Any useful comments will be most appreciated.
Trying to determine if smaller tubes should be used for sample collection from a 150 g rat vs 400 g rat.