Reproduction & animal behaviour
This page pulls together the reproduction, welfare and behaviour topics you need for KS4 and BTEC Level 2–3 Animal Care. Work through each section, learn the key terms, then test yourself with the self-check questions at the bottom.
Key terms to lock in
oviparous
viviparous
ovoviviparity
parthenogenesis
oestrus
luteinising hormone
ethogram
focal sampling
displacement behaviour
homeostasis
1. Reproductive strategies
Animals reproduce in very different ways. Being able to define and compare these strategies — and give an example species — is a common exam requirement.
- Sexual reproduction — the fusion of two sex cells (gametes) from two individuals. Offspring inherit a mix of genes from both parents, which increases genetic variation within a population.
- Asexual reproduction — no fusion of sex cells. Offspring are produced from a single individual, so they are genetically very similar to the parent.
- Oviparous — the animal lays eggs. The embryo develops inside the egg and hatches outside the mother’s body. This is common in reptiles and birds.
- Viviparous — live young. The young develop inside the mother (typically nourished through a placenta) and are then born. This is typical of most mammals.
- Ovoviviparity — a combination of both. Eggs are retained and hatch inside the mother, but there is no direct placental connection; the developing young are nourished by the egg’s yolk rather than by the mother.
- Delayed implantation — a fertilised embryo pauses its development before implanting in the uterus. This lets the mother time the birth to a favourable season or set of conditions.
- Parthenogenesis — a female produces offspring without a male fertilising the eggs. The young are usually genetically identical to the mother, which limits genetic diversity.
2. The canine oestrous cycle
The dog’s reproductive cycle runs through a fixed sequence of stages. Learn the order and know which stage ovulation happens in.
Anoestrus → Prooestrus → Oestrus → Metoestrus → Dioestrus
- Ovulation occurs during oestrus — this is when the egg is released from the mature follicle in the ovary.
- Luteinising hormone (LH) triggers the ovary to mature the follicle and release the egg (ovulation). A surge in LH is the immediate trigger for ovulation.
- Anoestrus is the resting phase; prooestrus is the build-up before the female is receptive; metoestrus and dioestrus follow oestrus.
3. Cattle & breeding notes
- Signs of heat (oestrus) in cattle — mucous discharge from the vulva, and standing to be mounted (“standing heat”) is the key behavioural sign.
- Superovulation — can be induced in a donor animal using injections of Follicle Stimulating Hormone (FSH) so that she releases many eggs at once, often for embryo transfer.
- Uterine torsion — the body or horn of the uterus twists, trapping the foetus. This is an obstetric emergency.
- Secondary uterine inertia — the uterus stops contracting effectively because of exhaustion, often after delivering a large litter.
- Eclampsia — a life-threatening drop in blood calcium in nursing mothers. It is an emergency and needs immediate veterinary treatment.
4. The five welfare needs (Animal Welfare Act 2006)
Under the Animal Welfare Act 2006, anyone responsible for an animal must meet its five welfare needs. Poor welfare is usually the result of inappropriate husbandry.
- A suitable environment — the right place to live.
- A suitable diet — the right food and access to fresh water.
- The ability to exhibit normal behaviour patterns — space and enrichment to behave naturally.
- Appropriate company — to be housed with, or apart from, other animals as its needs require.
- Protection from pain, suffering, injury and disease — including prompt veterinary care.
5. Animal behaviour terms
- Allogrooming — social grooming between animals of the same species; it helps build and maintain social bonds.
- Over-grooming / intergrooming — grooming taken to excess, which can point to stress or a health problem.
- Stereotypic behaviour — a repetitive behaviour with no obvious purpose or benefit, e.g. bar-biting or pacing; often a sign of poor welfare.
- Courtship — behaviour that leads to mating and reproduction.
- Foraging — searching for and gathering food.
- Displacement behaviour — occurs when an animal is torn between two drives (e.g. fear vs aggression). It often shows as an out-of-context comfort movement such as grooming or drinking.
- Intraspecific — interactions within the same species.
- Interspecific — interactions between two different species.
6. Behaviour sampling methods
To study behaviour objectively you record it using a set method. An ethogram (a catalogue of the behaviours a species shows) is usually drawn up first, then one of these sampling methods is used.
- Ad libitum sampling — note down anything interesting about one animal or group over a period. Quick and flexible, but biased toward eye-catching behaviour.
- Focal sampling — watch ONE animal for a set length of time and record everything it does.
- Scan sampling — record what an animal or group is doing at set time intervals, e.g. every 5 minutes.
Factors affecting behaviour
Many factors shape how an animal behaves. Be ready to list and explain several:
- Age, genetics, experience and learning
- Reproduction and health
- Environment and development
- Humans, social structure and communication
- Circadian rhythms (daily body clock)
- Predator–prey relationships and physiology
Homeostasis & the endocrine system
- Homeostasis — keeping internal conditions such as water levels and body temperature balanced so the body can function.
- The endocrine system — glands and organs that secrete hormones into the blood to regulate behaviour, seasonal changes, mating and parental care.
- Hormones to know: testosterone, oestrogen, progesterone, cortisol, oxytocin, vasopressin, melatonin, thyroid hormones, adrenaline and noradrenaline.
Feedback loops
- Positive feedback — amplifies a change until an outcome is reached, e.g. oxytocin intensifying contractions during childbirth until the young is delivered.
- Negative feedback — reverses a change to maintain homeostasis, e.g. sweating to cool the body back toward its set temperature.
Exam tip: when a question asks you to compare strategies (oviparous vs viviparous, positive vs negative feedback, intraspecific vs interspecific), always give a clear definition of each AND a worked example. The example is often where the marks are.
Self-check
What is the difference between oviparous, viviparous and ovoviviparity?
Oviparous animals lay eggs and the embryo develops and hatches outside the mother (e.g. most reptiles). Viviparous animals give birth to live young that developed inside the mother, usually via a placenta (most mammals). Ovoviviparity combines both: eggs are retained and hatch inside the mother, but with no direct placenta — the young are nourished by the egg yolk.
Put the canine oestrous cycle in order, and say when ovulation happens.
Anoestrus → Prooestrus → Oestrus → Metoestrus → Dioestrus. Ovulation happens during oestrus, when the egg is released from the mature follicle. A surge of luteinising hormone (LH) triggers ovulation.
Name the five welfare needs under the Animal Welfare Act 2006.
A suitable environment; a suitable diet; the ability to exhibit normal behaviour patterns; appropriate company (housed with or apart from other animals as needed); and protection from pain, suffering, injury and disease. Poor welfare usually results from inappropriate husbandry.
Explain the difference between focal sampling and scan sampling.
Focal sampling means watching ONE animal for a set period and recording everything it does. Scan sampling means recording what an animal or group is doing at fixed time intervals, e.g. every 5 minutes. Ad libitum sampling, by contrast, is just noting anything interesting as it happens.
Give an example of positive feedback and an example of negative feedback.
Positive feedback amplifies a change — e.g. oxytocin intensifying contractions during childbirth until delivery. Negative feedback reverses a change to keep the body balanced (homeostasis) — e.g. sweating to cool the body when it overheats.