Animal Classification &

Physiology

Learning Intention 17th October 2012

We are learning to:

•Distinguish between the different phylums and identify members of each phylum with an agricultural significance

Success Criteria 17th Oct 2012

• Students will:

• Be able to differentiate between the different phylums

• Be able to describe the life cycles of liver fluke and babesia

• Be able to name examples from every phylum

Set Induction 17th Oct 2012

• Identify different species in agriculture and their characteristics

*Go to animal test with solutions

Classification of Animals

• Kingdom • Phylum • Class • Order • Family • Genus • Species • This is a binomial system because they all have 2 names • E.g. Homo sapiens, poa annua, trifolium repens, Equus

caballus

Species Relating to Agriculture Phylum: Protozoa(Kingdom Protista)

• Single celled animals • Free-living in sea + freshwater

• Microscopic • E.g. Babesia – causes redwater in cattle • - transmitted by bites of a blood-sucking tick • - inside the cow it multiplies at a great rate

causing red blood cells to burst • - Causes anaemia, weakness, lack of thrive in

cattle • - it closely related to malaria in humans

Life Cycle of Babesia

Enters Tick

When tick

sucks blood

Vast increase

In numbers

By asexual reproduction

Transferred to cow

When tick sucks

Blood again

Diploid

Zygote

Form Gametes

By meiosis

How to tackle Redwater

• Vaccination (vaccinating pregnant cow)

• Topping + clean pastures

• No mixing of stock (good fencing)

• Rear your own replacements, do not buy in

Phylum: Platyhelminthes

• Flat worm

• Bilaterally symmetrical (have a front end and rear end)

• They are triploblastic (3 body layers) (edoderm, endoderm, mesoderm)

• Example = Liverfluke

Liverfluke (Fasciola hepatica)

• Hermaphrodite – will fertilise itself if no mates are available

• Oral and ventral sucker for feeding + attachment to the host

• They have a tough outer layer called the cuticle

• It is an obligate parasite (must live off another living host)

Liver Fluke

1. The fertilised eggs are egested via the small and large intestines.

2. If conditions are suitable, i.e. greater than 10°C and a pH of less than 7.5, the eggs hatch. The miracidium emerges from the egg-this stage is free living.

3. The miracidium has 24 hours to find a watersnail.

4. Once the miracidium enters the watersnail its body structure changes. It is now referred to as the sporocyst.

5. Asexual reproduction occurs inside the body of the sporocyst resulting in the next stage known as the redia.

6. Asexual reproduction occurs inside the body of the redia resulting in the next stage known as the cercarium.

7. The cercaria leave the body of the watersnail.

8. The cercaria uses its tail to swim up a blade of grass, there it encysts and waits to be eaten.

How can the Farmer prevent infection

• Dosing twice yearly (Anti-helminthic)

• Drainage of land

• Fence off wet land

• Clean pasture (rotational grazing)

• Liming – helps flocculation and therefore drainage

• Ducks + geese – predator of snail

• Molluscides – remove snail from pasture

Tapeworm (Class Cestoda)

• These belong to the same phylum

• They live in the intestines of farm animals

• Not a big problem because of regular dosing

• They have a cuticle to protect them

Phylum: Nematoda

• Round worms

• Free-living in soil – nematodes

- plant nematodes = eelworms

- animal nematodes = round worms

Features

- its round in the cross section

- they are not segmented

- pointed at both ends

- separate sexes

Roundworm

1. Female roundworms lay eggs that pass in the faecas of cattle.

2. Free-living larvae develop and hatch from the egg.

3. The larvae undergo two more stages of development. At this point, they infect cattle.

4. The larvae attach themselves to grasses that are ingested by the cow. They mature in the intestines of the cow and reproduce. Females can produce eggs two to four weeks after ingestion

Roundworm Life cycle

Homework 17th October

• 2000 1 d, 9d

• 2002 1 d

• 2006 1e

• 2007 1d

• 2011 Q5

Agricultural Examples

• Hoose/lungworms

• Ostertagia

• Nematodirus

• Potato eelworm

Recall 23rd October 2012

•Draw the life cycle of the liverfluke

Learning Intention 23rd October 2012

We are learning to:

•Distinguish between the different phylums and identify members of each phylum with an agricultural significance

Success Criteria 23rd Oct 2012

• Students will:

• Be able to differentiate between the different phylums

• Be able to describe the life cycles of for incomplete and complete metamorphosis

• Be able to name examples from every phylum

Set Induction 23rd Oct 2012

• Write down a short description of a earthworm

• What are the benefits of earthworms?

Phylum: Annelida

Features

• Round in cross section

• Segmented

• 4 pairs of bristles on each segment

• They have a body cavity called a coelome

• Clitellum (saddle)

Digestive System

• Earthworms are bulk feeders • They ingest large quantities of soil • Its stored in the crop • Its crushed in the gizzard • Some of the goodness is absorbed in the intestine • The rest is passed as wormcasts • Earthworms are harmaphrodite • They only cross fertilise

• The clitellum or saddle is the thickened band found on segments 32-37. Its function is fertilisation occurs there + it forms a cocoon for the developing eggs.

Phylum: Mollusca

• Snails, slugs, octopus, squid

• The main characteristic is they have a slimy foot

• They have a saw-like tongue called a radula

• Difference between slugs and snails is that slugs have no shell

Agricultural Importance

• Secondary host in the liver-fluke life cycle

• Pest on crops – damage crops

Phylum: Arthropoda

• Jointed limbs

• Exoskeleton

• Class: Arachnida

• 4 pairs of legs

• 2 body parts

• Class: Insecta

• 3 body parts

- head, thorax, abdomen

• 3 pairs of legs

• 2 pairs of wings

• Compound eyes

• This phylum contains 90% of all species on earth

• These animals regularly * moult

* (ecdysis = lose their exoskeleton + grow a new larger one)

• This occurs in an incomplete metamorphosis life cycle

Complete Metamorphosis Lifecycle

• Some of the anthropods undergo a complete metamorphosis lifecycle

• Examples of Complete Metamorphosis

- Caterpillar – Butterfly

- Leatherjacket – Cranefly (During larval stage all 3 eat roots & lower stems)

- Wireworm - Clickbeetle

Life Cycle of Aphids

• Centipedes

• Millipedes

• Woodlice

• Mites

• Ticks

• Flies

• Bluebottles

• Daddy long legs

• Beetles

• Mosquitoes

Parasites

• A parasite lives on another living organism • Ectoparasites live on the outside e.g. fleas, lice, ringworm, scabies,

aphids • Endoparasites live inside, they usually have a sucker for connection,

tough outer covering, they produce large numbers of eggs + are usually capable of asexual reproduction

• Protozoa Simple • Platyhelminthes • Nematoda • Annelida • Mollusca • Arthropoda • Chordata Advanced

Phylum: Chordata

• This phylum contains all backboned animals (vertebrates) • E.g. humans, cows, sheep, rats • There are 2 groups of importance in agriculture 1) Class: Aves (Birds) 2) Class: Mammalia • Warm Blooded - Birds + Mammals are the only warm blooded animals

meaning their temperature is regulated independently of their surroundings

• Cold Blooded - These animals take the temperature of their surroundings

e.g. snakes need to bask in sun to warm blood

Birds (Class: Aves)

• Feathers

• Light bones

• No teeth

• Different beaks according to diet

• No bladder – urine mixes with faeces

Class: Mammalia

• Mammals have hair

• Most mammals produce live young

• The unborn is nourished in the womb via the placenta

• Milk is produced from the mother for the offspring