9 Things About Sheep

9 Things About Sheep

Cognition and Intelligence

Cognition can be defined as the mental acquisition and integration of environmental stimuli. A species' cognitive capacity derives from evolutionary factors and how necessary it is for their survival. Cognitive processing is costly energy-wise, so unless resources are favourable enough after utilising the skills developed to obtain them, the sacrifice can detriment survival. Presence of complex/higher-end intelligence isn't always a blessing because it can overcomplicate something simple, such as inducing augmented boredom in sub-optimal captive environments.

As herd animals, sheep are capable of observational learning and 'social transmission' as a necessity for strength in numbers survival, functioning as a communal brain almost. For instance, individuals have watched other sheep traverse a maze, only to replicate the procedure themselves, demonstrating problem-solving and decision-making.

Another example is how lambs can copy/learn self-medication from their mother (if experienced). Despite sheep being known for innately searching for substances with pharmaceutical benefits when ill, the mother's presence is critical for the lamb's assurance - alongside knowing what to specifically search for, and more efficiently, e.g. anti-parasitic plants. Sheep can even counteract gastrointestinal parasites with anorexia, so they die of malnutrition.

Consequently, observational learning can relieve an individual's fear/uncertainty as a prey animal (most prominent in younger sheep) due to collective affirmation in numbers. When lambs are getting weaned, experienced adults mixed in serve as social 'models', where the lambs have to habituate to the trough, smell, texture and how to grasp and chew the food. If an adult's doing so already, it can incite them to partake and considerably impact transition speed - which can be a matter of days.

Furthermore, they have the capability of behavioural self-inhibition (less so in older sheep), willingly stifling an unsuitable impulse to attain a better outcome with a more passive approach for a given scenario. Having a linear route to food blocked off by a wide, transparent object that can't be broken or walked through may encourage insightful deductive reasoning to think 'outside the box' - option 1, headbutting won't work, so it's the alternative option 2 to go around the side. Otherwise, they could use trial and error to realise going around is required after trying to force their way through - which is less intellectual.

Facial Recognition

Due to social evolutionary pressures, sheep have specialised temporal cortex brain cells related to distinguishing individual adult sheep faces (with familiarity, gender and breed involved), other quadruped species - most notably dogs - and human biped figures. They struggle with determination if the eyes become obscured or if a human is on all fours - entailing posture and shape are identification factors. Orientation and viewing perspective are also intertwined, concerning whether the entity is forward-facing, approaching, or withdrawing.

The cells are coded preferentially for recognition of faces over shapes/symbols; furthermore, there are different populations of said cells - one for faces with horns including their size, one for sheep faces of the same breed and one for other animals such as humans and dogs. They gravitate more towards happy human faces as opposed to frowning ones.

Sheep can remember ~50 unique faces for around 2 years and even names, which is comparable to the capabilities of human and non-human primates. Other brain regions pertaining to behavioural + emotional responses only get stimulated when sheep are noticeably intrigued by the individual faces.

Anti-predatory Strategies

Like goats, sheep have a ~320-degree vision field partly due to their rectangular pupils, meaning no head turning is necessary for predator detection, so they can maintain vigilance and monitor other sheep positions while grazing, except for what's directly behind. Even then, they can smell you or can see behind through the legs when their heads are down.

Their vision grants sooner detection, resulting in a more lenient initial distance between predator and prey - while processing the corresponding reaction, which is limited. Sheep are very vulnerable and can only rely on fleeing (up to 20mph on land) plus safety in numbers as defence strategies; in fewer numbers, susceptibility gets emphasised, compromising foraging for heightened scanning rates and vigilance to compensate.

Philtrum and Selective Grazing

Sheep have an upper lip division named the 'philtrum', akin to a human's groove ('infranasal depression') just under the nose. It helps them as selective grazers, facilitating the separation of more desirable strands of grass through the opening - from other adjacent ones that may be less nourishing.

The philtrum also allows them to get their heads down lower to the ground, as they observably prefer grazing closer to the roots, unlike cows. Moreover, since they're selective, they can eat particular plants that afflict grassland biodiversity for overall maintenance - although enough sheep will destroy a whole ecosystem.

Distress and Emotions

In captivity, sheep are often gentle and tranquil in calm environments, aside from occasional hierarchical bickering and panicking from sudden stimuli. However, they are still predominantly natural prey animals, frequently on edge and alert, becoming easily distressed, overwhelmed and frightened. Sometimes, it's difficult to discern if they're in an acceptable state of well-being because they hide pain stoically to prevent exploitation by a potential predator.

Herd isolation or being lost can be particularly depressing and distressing for sheep, as they are highly sociable and are substantially more vulnerable alone. They can exhibit signs similar to that of humans like head hanging. Fortunately, lost sheep, at least, can return via scent marker pheromones of the herd - from glands in front of the eyes and in between the hindlimb digits.

Sheep are receptive to each other's emotions, including detecting anxiety in another sheep, most visibly by the subtle ear position changes, which are more indicative than the tail. The alterations often link with negative emotional states. Different positions could suggest...

Horizontal = neutral or maybe positive state - relaxed

Backwards = unfamiliarity, unpleasantness, fear in an uncontrollable situation

Up = similar to backwards but anger/frustration in a controllable situation - snorting can entail a warning/aggression

Asymmetric = startled e.g., sudden stimuli, pain

Some extent of associative predictability (in a positive sense) is paramount in a captive environment for them to feel more at ease, although not too much to mitigate boredom. Environmental predictability eventuates in sheep becoming optimists or pessimists based on their experiences.

They evaluate an environmental scenario for emotional preference based on familiarity, predictability, consistency with expectations, stimuli and general pleasantness. Allowing them control over environmental manipulation via enrichment will engage them - for example, a brush on a wall, a mirror, or a bounce-back punching bag for headbutting. Mirrors also somewhat relieve the affliction of isolation, with the sight of 'another' as a substitute for company.

Ewe-lamb Bonding

Ewe-lamb bonding after birth is vital for the welfare of both parties - resulting in a parental strategy of sensory recognition for lamb survival. Interfering with the process jeopardises long-term lamb sociality, inhibits physical development respecting nutrition and can induce substantial distress mutually.

Because sheep are 'maternally selective', the ewe 'marks' the lamb(s) with amniotic fluid odour as certification of her own - in order to distinguish the offspring from alien ones; so only they are allowed to get supplied with nutrients from suckling - helping the ewe to conserve energy as lactation is so demanding. Other ewe's lambs get rejected at the udder, often by an aggressive headbutt.

Bonds establish within the first few hours postpartum, with the first hour being essential, especially since it's the most rapid phase of development from positive interactions, for instance, suckling and grooming that invokes oxytocin plus anti-stress. Contact communication will significantly decrease as the lamb ages.

The lamb(s) will eventually learn the visual, olfactory, acoustic and tactile cues (likewise with the mother) to discriminate and prioritise their own mother for nurture - plus, avoiding rejection from other ewes. Lambs raised without ewes connect easier with humans if cared for and can get along with their goat relatives and cattle herds to deter predators.

Another type of their bonds is a worthwhile connection with particular conspecifics where they will stick up for them in fights if they're weaker/smaller and grieve without them.

Brain Cooling and Water Conservation

Sheep can reduce water loss via a counter-current heat exchange system in their brains to cool the blood. For a 50kg sheep, ~2.5 litres of water can get saved each day, utilising selective brain cooling for half of a hot day. Dehydrated sheep further enforce cooling up to 3x an elevated magnitude regardless of core temperature.

Arteries carrying blood towards the brain base split into thinner vessels called arterioles, where heat from said blood transfers out more efficiently into venous blood for cooling of the hypothalamus - which induces sweating function when hot - meaning water loss for limited benefit if they are unsheared. It's especially true for bigger ones with more wool - or black sheep that absorb heat more than white - so most heat loss is from panting, the ears and legs (extremities). Airflow through the nasal passage also aids heat loss concerning venous blood in the nasal mucosa (nose cavity lining).

Wool and Shearing

Domestic sheep have been bred for continuous wool growth, needing annual shearing, and rarely have hair, unlike wild ones. One individual sheep can go through ~10-15 kilos of wool a year; their coats can get so thick that they can run through or roll over barbed wire unfazed. Super woolly sheep like the merino breed can get impeded vision and joint and movement issues from being weighed down. Some cannot right themselves if upside down as they can get so heavy, dying if no help is received.

The world record was a merino sheep called 'Shrek', who carried just over 40kg of wool after hiding for years (the result shearing can have) to not get sheared, only for it to happen on live TV. He had enough wool for ~20 average-sized men's suits and could've made almost up to 900 miles of yarn if it were as thin as possible. Sheep are susceptible to overheating, let alone Shrek, so shade in the summer is crucial as opposed to warmth in winter - the wool fleece contains a waxy substance called 'lanolin', which has waterproof properties to stay dry in wet weather.

It may not be feasible, though it would be ideal if sheep could go to various locations with different staff for shearing, so there would be a lower risk of chronic distress and hyperthermia from fear and vigilance associated with certain stock persons or facilities because of possible aversive memories from handling/restraint.

They are unlikely to acclimate long-term to rough handling and fright, leading to white blood cell decline and diminished immunity. Still, positive reinforcement methods could help them adjust to become more comfortable in a given situation. For example, a desirable food like barley, specifically fed after getting moved for transport, subsidising more value in the food as a rarity and perhaps compelling the sheep to view transport as a reward if the food is worth the ordeal. Overall, it's more engaging for the sheep and less arduous for the workers.

Anyway, wool is dust mite resistant and not susceptible to fire - the average composition consists of ~60% protein fibres, ~15% moisture, ~10% fat, ~10% sweat and ~5% contaminants of primarily bacteria. Greasy wool is higher in bacterial contaminants, therefore being classed as 'special' waste with expensive disposal, where people burn or bury it, which detriments the environment.

Wool is eco-friendly and renewable, with versatile applications such as thermal insulation and acoustic absorption - both performing similarly to synthetic materials, which is more sustainable, saving money and lessening carbon dioxide emissions/pollution instead of burning or burying. Other implementations involve material transport and fortifying concrete for flexural strength.

Foot Rot

Foot rot is a prominent cause of lameness in ungulates, being contagious and a dangerous bacterial infection. Transmission is highest in warm, humid, wet and congested environments. For non-benign variants, there are vaccinations, anti-microbials and disinfectant foot bathing for treatment - except being expensive. Foot trimming is unneeded and damaging, ironically contributing to lameness.

For more severe virulent cases, there's euthanasia as a last resort for ending suffering and protecting the remainder of the herd for the greater good. Prevention will always be better than resolution to avoid pain, discomfort, distress and suffering for animal well-being.