hello,

There is no custom app for slaughtering. What you can do is take Odoo and make the slight changes to manage the extra information you may need.

1. Animal Purchasing : You should be able to use the purchasing app 

2. Ante Mortem and Lab Tests: You should be able to use the quality app

3. Slaughtering Process: You may use the prodcution process

4. Post mortem and Lab Reports: Not sure what this is, but if it is quality testing after production, then you could use Odoo quality management.

5. Chilling and Packing: Odoo inventory management. 

6. Gate Pass management: No clue what this means. Let us know in order to get some feedback.

Basically, you may represent your business with Odoo. You can contact me inbox to get more information.

Good Luck!

Eva P.