Unit 3 KA4-KA6 Flashcards
(29 cards)
Animal welfare
Animals should be able to:-
Grow
Reproduce & bring up offspring successfully Resist disease
The Farm Animal Welfare Council state that domesticated animals should also be able to express their normal, natural behaviour patterns.
Costs&benefits
Providing improved environmental conditions for domesticated animals to increase animal welfare is expensive and leads to produce which is more expensive (animal products from Britain are more expensive than those imported from other countries which have lower standards of animal welfare).
However, contented, unstressed animals grow better, breed more successfully and produce better quality products, so the long-term benefits are worth it.
Ethical issues
Intensive farming is less ethical than free range farming due to poorer animal welfare.
Free range requires more land and is more labour intensive. However, the produce can be sold at a higher price and the animals have a better quality of life.
Intensive farming often creates conditions of poor animal welfare. However, it is more cost effective, generating higher profit as the costs are low.
Behavioural Indicators of Poor Animal Welfare
Stereotypy
Misdirected behaviour
Failure in sexual or parental behaviour
Altered levels of activity
Stereotypy
This is repetitive movement often displayed by animals kept in bare/confined areas (e.g. pigs in small pens often make continuous chewing movements without having food in their mouths; lions in a small zoo enclosure often pace up & down the same path).
Misdirected behaviour
This is where a normal behaviour pattern is inappropriately directed towards the animal itself, another animal or its surroundings (e.g. over-grooming of feathers). This commonly happens in animals which are confined or are kept in isolation.
Failure in sexual or parental behaviour
Poor welfare and prolonged isolation can result in animals failing to reproduce successfully or rejecting their offspring and and failing to be effective parents.
Altered levels of activity
A very high level of activity (hysteria) such as hyper-aggressive stamping or very low level of activity (apathy) such as excessive sleeping indicates that the animal may be suffering as a result of poor welfare.
Symbiosis
Symbiosis are co-evolved intimate relationships between members of two different species.
There are two types of symbiotic relationship:-
parasitism mutualism
Parasitism
In this relationship, the parasite benefits at the expense of the host.
It may live inside the host (e.g. tapeworm) or outside the host (e.g. flea).
The parasite depends on the host for energy and
nutrients; the host is harmed by the loss of these resources.
Parasites often have limited metabolism (e.g. a tapeworm doesn’t have a digestive system). This means that they can’t survive if they lose contact with their host. The most successful parasite is one that doesn’t cause the host to die.
Mutualism
This is an interdependent relationship in which both mutualistic partner species benefit.
Grazing herbivores (e.g. cows) have cellulose digesting bacteria within part of their stomach. These bacteria digest cellulose for the herbivore (the herbivore itself does not have the enzymes responsible for breaking down cellulose). In return, the bacteria gain a safe, warm, moist habitat and a food supply from the herbivore’s gut.
Transmission
There are three methods of transmission –
a) direct contact e.g. headlice
b) resistant stages (these can survive adverse conditions for long periods until they come into contact with a host) e.g. cat flea larvae/pupae
c) by vectors e.g. the mosquito carries the organism Plasmodium which causes malaria
Some parasitic lifecycles involve intermediate
(secondary) hosts to allow them to complete their life cycle.
Example of transmission
e.g. the pork tapeworm has the human as its primary host and the pig as its secondary host. The human obtains the tapeworm by eating infected, undercooked pork; the pig becomes infected when it eats grass containing eggs or segments of tapeworm.
The tapeworm can only complete its lifecycle and produce eggs inside a human but it is unlikely to move into another human unless their food or drink is contaminated with raw sewage. It therefore needs the secondary host, the pig, to be transferred to another human and relies on the meat being undercooked for this to happen.
Social behaviour
Many animals live in social groups of various sizes. The animals within each social group have behaviours that are adapted to group living. Such behaviours include:- Social hierarchy Cooperative hunting Cooperative defence
Social hierarchy
This is a rank order within a group of animals consisting of dominant and subordinate members.
In a social hierarchy, dominant individuals carry out ritualistic (threat) displays whilst subordinate members carry out appeasement behaviours to reduce conflict.
Social hierarchy in birds
Social hierarchy takes the form of a pecking order - the most dominant bird pecks and intimidates all the other birds within the group without being pecked in return. This bird gets the first choice of food.
The second bird pecks all the other birds except the first and so on. The most subordinate bird at the bottom gets pecked by all the other birds but doesn’t peck any birds itself.
Social hierarchy in wolves
The dominant animal gets the first choice of food, sleeping place and mate.
The dominant wolf displays threat gestures:-
raises his head, ears, tail & hackles
bares his teeth
has staring eyes
The submissive wolf:-
lower its head, ears, tail & hackles
covers its teeth
averts its eyes
Advantages of social hierarchy
- They increase the chances of the dominant animal’s favourable genes being passed on to the offspring.
- Animals often form alliances in social hierarchies to increase their social status within the group.
Cooperative hunting
This is where predators work together to hunt for and catch prey.
e. g. wolves take turns at running down a single prey animal, which becomes exhausted and easy to catch
e. g. some lions within the group drive prey animals towards other lions lying in wait (ambush strategy)
Advantages of cooperative hunting
Less energy is used per individual animal
Enables larger prey to be caught and increases the chances of success Subordinate animals benefit as they gain more food than by foraging alone
Cooperative defence
This means that groups adopt specialised formations when under attack to protect their young. In a large group, they rely on “safety in numbers” as a means of defence. These strategies increase the chances of survival as some individuals can watch for predators whilst others can forage for food.
Examples include:-
Flocks of birds which bunch together and swirl following an alarm call to confuse the predator and make it difficult for one prey animal to be picked out and captured.
Quails, which roost in circles with their heads to the outside. They confuse their
predators by “exploding “ in their face – during the confusion, they fly to safety.
Musk oxen form a protective group around females and young when threatened - mobbing. The huge-horned males on the outside then either gore single predators or drive off packs of predators, so protecting the others.
Altruism
Normally members of the same species compete selfishly to obtain the resources they need to survive.
Occasionally, however, an animal behaves in a way that benefits the other animals (the recipients) but is harmful to itself (the donor). This is known as altruism.
Reciprocal altruism
This involves the roles of the donor and recipient later reversing, often occurring in social animals.
e.g. vampire bats
Vampire bats who have successfully gained food whilst hunting may share the food with others who have not been successful.
The benefit gained by the recipient exceeds the cost to the donor (a hungry bat will most likely die
after two nights of not feeding).
Kin selection
Behaviour that appears to be altruistic can be common between a donor and recipient if they are related (kin).
Individuals (donors) will benefit in kin selection in terms of the increased chances of survival of the shared genes in the recipient’s offspring or future offspring.
