Fish Respiratory system

1- Fish Gills extract 02 dissolved in water.

2- Water enter through mouth ,then flows over gills then to outside.

3- Water pumping occurred by opening mouth and operculum while swimming.

تتنفساألسماك الذائبفي األكسجين

في الماء الماء ويمراتجاه في مستمر تيار

ثم الفم من واحدالى ثم الخياشيم

بهذا الماء ويضخ الخارجنتيجة الفم الشكل فتح

الخيشوم اثناء وغطاءالسباحة.

GILLS = BRANCH = خياشيم

THE GILLS :

1- Gill ARCH.

2- Gill Filaments.

2- Gill Rakers .

3- Branchial Arteries (Afferent and Efferent ).

4- Adductor and Abductor Muscles.

The Gills two sets Four on each side

of pharynx.

1- Gill Filaments :

Each Gill arch attached to it two Rows of Gill filaments .

Two rows of filaments = Holobranch.

One row = Hemibranch .

So each Holobranch formed of two Hemibranch.

Long thin gill filament called primary lamellae.

Each primary lamellae has semilunar folds across their dorsal and ventral surfaces called secondary lamellae.

2- Gill Rakers الخيشومية :األسنانcartilaginous or bony tubercles on cranial aspect of gill arch prevent food particles from reaching respiratory components of gills. So save fish from suffocation.

Complete the following diagram?

1 -Title=

2-

3-

4 -

2 4

3

Mechanism of respiration in fishes :1- Oxygen taken by diffusion through thin membranes of gill secondary lamellae.

2- Blood and water move in opposite directions allow gas exchange and that called counter current mechanism.

Differ between gills of Bony and cartilaginous fishes?

Fish cardiovascular system:

1- Fish Heart.

2- Fish Blood Circulation.

Fish HEART :

1- Sinus Venosus. الوريدي الجيب2- Atrium. األذين3- Ventricle.البطين 4- Bulbus Arteriosus. البصلة الشريانية

There are dorsal and ventral aortae in fishes.

Afferent Branchial arteries carry non oxygenated blood from Ventral Aorta to Gills.

Efferent Branchial arteries carry oxygenated blood from Gills to Dorsal Aorta then to different parts of body.

Labrynthine organ or Arborescent organ in

Cat Fish caudal to Gill help it to

Respirate oxygen from air.

Swim bladder (gas or air ) bladder: The organ of Buoyancy

Swim bladder:

Is a blind sac present on dorsal aspect of body just ventral to vertebral column and dorsal to gut.

May be one chamber :Tilapia.

Two chamber : carp.

Physostomous fish the swim bladder is connected to gut by pneumatic duct.

Physoclistous' = The connection with the gut is closed and no gas can be moved from the gut to the swim bladder,

Gas exchange is through the capillaries ‘Rete mirabile', and the membrane of the air bladder. The capillaries arranged in a counter-current system to facilitate the creation of high gas pressures within the swim bladder.

1- OVIPAROUS FISHES:

1 -Demersal eggs. (fresh water fishes)

Eggs with adhesive membranes: stick to bottom and to each other

Eggs with adhesive threads : cling to plants and objects.

Non adhesive : Mouth brooding : eggs carried by parents in buccal cavity as in male tilapia (buccal incubation).

2 -Pelagic eggs (sea water fishes).

Contain oil drops so suspend in water

3 -Egg cases or baskets.(coral reef fisahes):

Horny cases produced by sharks and skates cling to rocks or coral , shape: box like, flat, spiral.

Methods of Reproduction

fry escape into mouth of male (father) fry stored in mouth of male (father)

Mouth Brooding

3 -VIVIPAROUS:

1 -Fertilization internally.

2 -Mother has PLACENTA LIKE ORGAN.

3 -In SURF PERCH (ovary) and shark ( ( UTERUS)UTERUS)..

2 -OVOVIVIPAROUS:

1 -Fertilization internally.

2 -Eggs have enough yolk to embryo development.

3 -In Electric rays and Dog fish shark. .

TESTIS : (MALE SEX ORGAN):

TRIANGULAR – FLAT – CREAMY OR WHITE IN COLOR.

SITUATED IN COELOMIC CAVITY – DORSOLATERAL TO GUT.

SUSPENDED BY MESORCHIUM.

OVARIES : ( FEMALE SEX ORGAN):

LONGITUDINAL ORGAN – PINKISH IN IMMATURE AND AMBER YELLOW IN MATURE.

SUSPENDED BY MESOVARIUM.

FISH REPRODUCTIVE SYSTEM

THE COPULATORY ORGANS

IN CHODROSTS : CLASPERS.

IN TELEOSTS: GENITAL PAPILLA ( projection form male genital opening) to pour semen for fertilization.

URINARY SYSTEM

THE KIDNEY :

In fishes kidney is Mixed Organ : Hematopoitec (blood forming) , Endocrine and Excretory.

Located Retroperitoneal ( ventral to vertebral column).

Fish has : Cranial (Head ) kidney Hematopoitec and Caudal kidney (Excretory).

Embryo has two kidneys fused completely in adults . As in Salmon>

Or two separate organs as in Anglerfish.

The Ureters:

Open Caudal To Anus.

Form a bladder in Tilapia.

Fish digestive system

Mouth

Feeding during swimming forward Feeding at surface Feeding from

Bottom

TEETH IN TELEOSTS:

1- MANDIBULAR.

2- MAXILLARY.

3- PALATINE

4- LINGUAL

5- PHARYNGEAL

TEETH IN CHONDROSTS:

1- MANDIBULAR.

2- MAXILLARY.

ANUS

pharynx

Esophagus

THE PHARYNX البلعوم :1 -It form with oral cavity , the Oropharynx.

2 -It contains Gill arches ,pharyngeal teeth occurred in these arches.

The esophagus :المرىء1 -short tube.

2 -separated from stomach by slight constriction

3 -Histologically : not contain gastric glands.

The stomach المعدة:U or V shaped tube :

Cardia = at which esophagus open.

Pyloric opening = between it and intestine األمعاء

Pyloric Caeca:

Blind ending diverticula = اعورية ردوبArise from distal part of pyloric region in stomach and cranial part of intestine.

Their number 70 or more.

Histologically resemble those of intestine rather than stomach.

Intestine:

The intestine is a simple tube has nearly the same diameter.

Short in Carnivores fishes and long in Herbivore fishes.

Shape of intestinal mass may be straight segmoid (s shaped) or coiled.

Following small intestine the Rectum

Rectum wider than it and contain rectal glands .

Rectum ends in Cloaca in Chondrosts.

as Anus in Teleosts.

The liver

Reddish brown in carnivores.

Lighter brown in herbivores.

In Tilapia forms with The Pancreas a compound organ named Hepatopancreas.

Bilobed in common

Unilobed in Salmon and Trout.

Trilobed in mackerel.

Its Bile Ducts fuse to form Gall Bladder containing greenish yellow bile.

FISH T.B