two articles on precautions during such study is attached. Is something missing in your protocol?

Principles of Bone Marrow Transplantation (BMT): Providing Optimal Veterinary and

Husbandry Care to Irradiated Mice in BMT Studies

Standard Operating Procedures for Rodent Irradiation & Bone Marrow Transplant Procedures (LabAn SOP 1)

Thanks Mr. Mushtaq but I have this 2 papers. May be my irradiation dose is still too high for Balb/c mice. I'll try to reduce again and see the effect. 

with reference to "Principles of Bone Marrow Transplantation (BMT): Providing Optimal Veterinary and Husbandry Care to Irradiated Mice in BMT Studies" dose given to mice was appropriate. please see the pages 15 and 16.

BALB/c mice are very sensitive to irradiation [42,50]. Whereas the commonly used B6 mice can typically tolerate a radiation doses of 1000 to 1100 cGy [25], the LD50 of TBI in BALB/c mice is about 880 cGy [42]. If given higher doses, BALB/c mice develop considerable radiation-induced sickness (lethargy, inappetance, diarrhea) that may lead to death. Therefore milder irradiation doses [87] should be used with BALB/c mice to avoid unnecessary irradiation-induced deaths. However, in recent disease studies of GVH and GVL using BALB/c mice as recipients, radiation doses of 800cGy were well-tolerated [27]. Others have used similar radiation regimens in BALB/c mice [28].

We use 850 cGy when transplanting BALB/c and the mice that didn't receive BMT die 14-21days after BMT. 

With contaminated mice they can die early. To minimize you can give acid water (ph 3 - 3.5) to mice drink ad libitum 2 weeks before the BMT and maintain 2 weeks after the BMT. 

Thanks Rômulo Galvani. I decreased the irradiation dose to 650cGy and the mice died from D8-D12. I'll try and see.

Have you reproduced these unexplainable findings?

Hi Dirk van Bekkum, I have done the irradiation. Just wait and see the outcome. 

Hi Romulo, Would you please send me your protocol? I'm interested in delayed BMT to 800 cGy irradiated Balb/c mice. (I'm looking into GVHD model). Thanks heaps

Hi all,

Most of the literature out there related to BALB/cJ GVHD models, suggest using split-dose radiation, within 800rads. Could we also extrapolate these numbers to a single dose? or would you suggest going higher? - any experience.

Thank you all in advance.

Harold