Pregledom dosadašnjih istraživanja uspoređena je mikroskopska građa organskih sustava morskih sisavaca, prvenstveno dobrog dupina s mikroskopskom građom domaćih životinja. Želudac je složen i sastoji se od predželuca, te fundusnog i piloričnog dijela. Značajna karakteristika dišnog sustava je velika količina elastičnog tkiva koja omogućava puno brže i intenzivnije izmjenjivanje zraka, a omogućeno je iskorištavanje puno veće količine udahnutog kisika čak do 90%. Mokraćni sustav dobrog dupina karakterizira izrazita režnjevitost bubrega pri čemu svaki režanj predstavlja zaseban bubreg, renculus. Bijelo tijelo s jajnika dobrog dupina, ali i nekih drugih morskih sisavaca, nikad u potpunosti ne iščezava. Jedna od glavnih specifičnosti muškog spolnog sustava utvrđena kod plavobijelog dupina, ali ne i kod dobrog dupina, je sezonalnost parenja. Također, istraživanja su pokazala da je kod obje vrste dupina šupljikavo tijelo penisa slabije razvijeno i spojeno je u jednu masu. Spolni ud pripada fibroelastičnom tipu, koji nalazimo još kod svinje i kod preživača. Živčani sustav karakterizira znatno slabije razvijen dorzalni (senzorički) u odnosu na ventralni (motorički) rog kralježničke moždine. Mjestimično se kod dobrog dupina teže razaznaju slojevi kore velikog mozga ,ali su prisutni svi tipični slojevi kore jednako kao kod domaćih životinja. Hipofiza odstupa od one kod kopnenih sisavaca i to svojim oblikom i rasporedom tipičnih dijelova. Aorta ima znatno deblju stijenku nego aorta domaćih životinja s dosta elastičnih lamela, a Purkinjeova vlakna srca smještena su bliže endokardu zbog zaštite tih vlakana od promjene tlakova. Limfni čvorovi dobrog dupina nemaju jasno odvojenu koru i srž te su limfni čvorići prisutni po cijelom organu. Koža dobrog dupina ima izrazito debeli epitel na kojemu je zaštitni parakeratinozni sloj. Morski sisavci svojom su morfologijom dobro prilagođeni uvjetima života u vodi uslijed čega je došlo do određenih promjena u makroskopskoj i mikroskopskoj građi pojedinih organa i organskih sustava iako osnovna shema mikroskopske građe odgovara onoj u sisavaca općenito.

A review of this research compared the histology of the organ systems of marine mammals, primarily bottlenose dolphin with the microscopic structure of domestic animals. The stomach is complexed and consists of forestomach, pyloric, and fundic part. A significant feature of the respiratory system is the large amount of elastic tissue, which provides a much more intensive exchange of air, and exploits a much greater amount of inhaled oxygen up to 90%. Urinary System of the bottlenose dolphin is characterized by highly lobulated kidney where each slice is a separate kidney, renculus. White body of the ovary of the bottlenose dolphin, and other marine mammals, never completely disappears. One of the main specifics of the male reproductive system established at the striped dolphin, but not in the bottlenose dolphin, and it is the seasonality of mating. In addition, studies have shown that in both types of dolphins cavernose body of penis less developed and connected in one mass. Penis belongs fibroelastic type, which we find in pigs and ruminants. The nervous system is characterized by considerably less developed dorsal root (sensory) in relation to the ventral (motor) horn spinal cord. Partially, in the bottlenose dolphin is harder to make all layers of the cerebral cortex, but they are present, and has all typical layers of the cortex as well as in domestic animals. Pituitary differs from that of terrestrial mammals to their shape and arrangement of typical parts. The aorta has a much thicker wall than aorta domestic animals with many elastic lamellae, and the Purkinje fibers of the heart are located closer to the endocardium for the protection of these fibers from pressure changes. Lymph nodes of bottlenose dolphins have not a distinct cortex and medulla, and lymph nodes of these types are present all over the body. Leather of the bottlenose dolphin has extremely thick epithelium with protective parakeratin layer. Marine mammals has its morphology well adapted to living conditions in water as a result of which there have been some changes in the macroscopic and microscopic structure of individual organs and organ systems, although the basic scheme of the microscopic structure corresponds to that in mammals in general.