G 18 is a good option

A 18-gauge needle .(Rosa Paparcone et al.Sternal Aspiration of Bone Marrow in Dogs: A Practical Approach for Canine Leishmaniasis Diagnosis and Monitoring,Journal of Veterinary Medicine Volume 2013 (2013), Article ID 217314, 4 pages,)

Sternal BM aspiration was performed using a one-inch, 20-gauge (for dogs > 9 kg) or 22-gauge (for dogs < 9kg) hypodermic needle (TICO, Pointe-Claire, QC, Canada) attached to a 12cc-Luer Lock-syringe (TICO) containing 1% sterile EDTA in 0.6 mL saline (.Reference: Dr. Bienzle.Comparison of sternal, iliac, and humeral bone marrow aspiration in Beagle dogs.

The sternum has historically not been aspirated in animals because of concerns about thoracic penetration.[1, 10] However, the sternum has less soft tissue coverage than the ilium, femur, or humeral head; a thinner cortex is readily accessible and yielded a diagnostic BM aspirate in fungal osteomyelitis.[8, 12, 13] Aspiration from the sternum in mildly sedated dogs was associated with less pain than from the ilium, suggesting that general anesthesia may not be required for this site.[12] Therefore,  Careful sternal BM aspiration may be practical, safer in critically-ill patients and more cost-effective.

Article Comparison of sternal, iliac, and humeral bone marrow aspira...

Article Sternal Aspiration of Bone Marrow in Dogs: A Practical Appro...

G18 would be appropriate if doing BMA on an adult dog weighing over 20lbs. If below 20lbs, go with smaller sizes (e.g. 20 or 22). In either case, be cautious of not penetrating into the thoracic cavity.

Hi Pradeep

Some useful references on attachment 1

https://www.hindawi.com/journals/jvm/2013/217314/

2

https://www.scielo.br/pdf/abmvz/v66n6/0102-0935-abmvz-66-06-01751.pdf

3

https://onlinelibrary.wiley.com/doi/10.1002/vms3.36/full

4

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=10&cad=rja&uact=8&ved=0ahUKEwjC8tKd7KzWAhVCYpoKHXiBDWAQFghMMAk&url=http%3A%2F%2Fveterinarymedicine.dvm360.com%2Fskills-laboratory-how-collect-diagnostic-bone-marrow-samples&usg=AFQjCNFw6ClMBxNa_t3FBtL66Gv5vXwlLw

5

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=10&cad=rja&uact=8&ved=0ahUKEwjC8tKd7KzWAhVCYpoKHXiBDWAQFghMMAk&url=http%3A%2F%2Fveterinarymedicine.dvm360.com%2Fskills-laboratory-how-collect-diagnostic-bone-marrow-samples&usg=AFQjCNFw6ClMBxNa_t3FBtL66Gv5vXwlLw

6

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=11&cad=rja&uact=8&ved=0ahUKEwjC8tKd7KzWAhVCYpoKHXiBDWAQFghTMAo&url=http%3A%2F%2Fwww.cliniciansbrief.com%2Fsites%2Fdefault%2Ffiles%2Fattachments%2FBone%2520Marrow%2520Sampling.pdf&usg=AFQjCNF9A2irlZPNO6_3aDV5i_nnnM0L2w

7

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=12&cad=rja&uact=8&ved=0ahUKEwjC8tKd7KzWAhVCYpoKHXiBDWAQFghZMAs&url=https%3A%2F%2Fwww.cliniciansbrief.com%2Farticle%2Fbone-marrow-aspiration-biopsy&usg=AFQjCNF8AJ9Dp8emCp7deI8ubshZiZ2fyQ

8

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=13&cad=rja&uact=8&ved=0ahUKEwjC8tKd7KzWAhVCYpoKHXiBDWAQFgheMAw&url=http%3A%2F%2Fwww.unboundmedicine.com%2Fmedline%2Fresearch%2Fsternebra&usg=AFQjCNGeKHfmWBycN460_MMSSV0vVlVVuQ

9

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=14&cad=rja&uact=8&ved=0ahUKEwjC8tKd7KzWAhVCYpoKHXiBDWAQFghgMA0&url=https%3A%2F%2Fveteriankey.com%2Fbone-marrow-examination%2F&usg=AFQjCNEmN91NOP-0icg4iVVk6MVrK_tF9g

10

https://www.canadianveterinarians.net/documents/2012-cvma-scientific-presentation

11

https://journals.sagepub.com/doi/full/10.1177/0192623310396907

12

https://www.roavs.com/pdf-files/Issue-1-2017/14-19.pdf

13

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=14&cad=rja&uact=8&ved=0ahUKEwiYiaK47azWAhVxSZoKHZRqAQI4ChAWCDQwAw&url=http%3A%2F%2Fwww.google.com.pg%2Fpatents%2FUS20150017145&usg=AFQjCNGpf8fbFzAs7UamKN2RzHPNc8QxLw

14

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=17&cad=rja&uact=8&ved=0ahUKEwiYiaK47azWAhVxSZoKHZRqAQI4ChAWCD0wBg&url=http%3A%2F%2Fscholar.cu.edu.eg%2F%3Fq%3Dhanem%2Ffiles%2Fmonograph__on_fungal_diseases_of_cats_and_dogs_april_2016.pdf&usg=AFQjCNEZnTc9CgqQdscG8up4hZYLWRED7g

15

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=18&cad=rja&uact=8&ved=0ahUKEwiYiaK47azWAhVxSZoKHZRqAQI4ChAWCD8wBw&url=http%3A%2F%2Fwww.pubpdf.com%2Fsearch%2FBone%2BMarrow%2BAspiration%2Band%2BBiopsy%2F8&usg=AFQjCNEFNTtskyWGT6vyp8nJhQNQTl5gdA

16

https://www.acvr.org/sites/default/files/2012-acvr-proceedings.pdf

17

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=20&cad=rja&uact=8&ved=0ahUKEwiYiaK47azWAhVxSZoKHZRqAQI4ChAWCEowCQ&url=https%3A%2F%2Fwww.accessdata.fda.gov%2Fdrugsatfda_docs%2Fnda%2F2012%2F203214Orig1s000PharmR.pdf&usg=AFQjCNFs19qAoavsOFoFzhgvuYQ3GsOqgA

18

https://es.scribd.com/document/233147465/Cytology-in-Food-Animal-Practice

19

http://www.ema.europa.eu/docs/en_GB/document_library/EPAR_-_Public_assessment_report/human/002755/WC500156105.pdf

20

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=25&cad=rja&uact=8&ved=0ahUKEwjsr7zb96zWAhXDK5oKHWWcB7Q4FBAWCDkwBA&url=http%3A%2F%2Fdocslide.net%2Fdocuments%2Fthoracoscopic-assisted-lung-lobectomy-in-the-dog-report-of-two-cases.html&usg=AFQjCNFJQUuXP66gSIyF2c6f_HpINohEnQ