Abstract
Background:
Apoptosis is crucial in avoiding excessive fibroblast proliferation and extracellular matrix precipitation several growth factors present in Platelet-rich Plasma (PRP) and collagen from Tilapia Mozambique (TM) worked in synergy to hasten auto skin graft (ASG) healing.

Aim:
This research aimed to evaluate the difference in histopathology and the expression of caspase-3 on ASG between those treated by TM skin bio-dressing and those given PRP and treated by TM bio-dressing.

Methods:
The research used 9 male local cats aged 2-3 years old, weighing 3-4 kg, which were divided into three groups. The first surgery for creating a defect forelimb of 2 x 2 cm in size was performed all cats, the wound was treated with ASG. Post ASG surgery, the cats were treated by moist dressing (Control/Group-I [G-I]), treated with only TM bio-dressing (G-II) were given PRP and treated with TM bio-dressing (G-III). The skin biopsy occurred on day 21 post-ASG to be made into a histopathology preparate stained by hematoxylin-eosin (HE), Masson’s trichrome (MT), and immunohistochemistry (IHC) against caspase-3 expression.

Results:
The HE staining result on the thickness of the epithelial tissue (epidermis), hair follicle, sweat gland, sebaceous gland, and neovascularization appears to be better in cats given PRP and treated with TM bio-dressing (P<0.05). The MT staining result on average collagen density showed that G-III is less dense compared with G-I and G-II (P value P<0.05). The IHC staining for immunopositively cells against caspase-3 in G-III, the cells are distributed in hair follicles, sweat glands, sebaceous glands and around blood vessels, while in G-I and G-II, the cells are distributed in hair follicles and sweat glands.

Conclusion:
The administration of PRP coupled with TM bio-dressing treatment (G-III) has better results in terms of tissue structure formations, collagen tissue density, and caspase-3 expression. Thus, the treatment is recommended to be used for ASG in cats.

Key words: Tilapia bio-dressing; Platelet-rich plasma; Caspase-3.