Hello,
Thanks for posting your query.
Red chunk in the semen is suggestive of blood in it. There could be many reasons for blood in semen.
Anything related to male genitourinary system can lead to this.
The reasons could be many, some of them are,
There can be infection any where in the tract (urethra, prostate, seminal vesicles)
Trauma somewhere in tract may be due to some procedure or otherwise
Some condition of prostate
Stone in the tract (seminal vesicles)
It is better that you visit a urologist for this and get your self evaluated to know the reason.

Urologist after examination may advise some tests, like urine test, ultrasound and other tests as per the need.

Management depends upon the diagnosis.
I hope this answers your query.
In case you have additional questions or doubts, you can forward them to me, and I shall be glad to help you out.
Please accept my answer in case you do not have further queries.
Wishing you good health.
Regards.
Dr. Praveen Tayal.

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