Plus-Hex CLINICAL
Introduction
The guinea pig ( Cavia porcellus ) species originates from South America and belongs to the Hystricomorpha (‘ porcupine-like ’) suborder of rodents [ 1 ] . This differs physiologically and anatomically from the Myomorpha (‘ mouse-like ’) suborder of rodents , which includes the rat , mouse and hamster . The taxonomic characteristics of guinea pigs ( also known as cavies ) should inform considerations around dietary , environmental and health factors to maintain the optimum welfare of individual animals .
Guinea pigs are increasingly common household pets , with around 400,000 estimated to be owned in the UK [ 2 ] . The species had been widely considered a lowmaintenance ‘ children ' s pet ’, which may have distracted from its complex welfare needs ; however , more recently , a survey revealed an awareness of the welfare needs of guinea pigs among owners [ 2 ] . Veterinary nurses ( VNs ) and the wider profession are key to raising awareness of guinea pig welfare and advocating for positive change .
Learning outcomes
• An understanding of the basic nutritional and husbandry needs of domestic guinea pigs
• Knowledge of the factors contributing to a range of health conditions in the UK ' s guinea pig population
• An awareness of the recommendations for planning and implementing effective guinea pig welfare consultations in a clinical setting
Anthrozoology
Cavies are native to the Andean region of South America , where their domestication is believed to have begun around 5,000 BC . Here , they were kept as livestock and farmed as a reliable source of meat , and they are still widely farmed and consumed in Peru and Bolivia [ 3 ] . Cavies were introduced into Europe in the 16th century by Dutch traders , where they were bred for showing by fanciers for around 300 years , before finding popularity as laboratory research subjects . The domestic cavy may have developed the nickname ‘ guinea pig ’ from their resemblance when cooked to the domestic pig , and the name of the coin , a guinea , for which they could be purchased from the traders [ 4 ] .
By the 21st century , guinea pigs had become popular companion pets , and it is estimated that approximately 1.3 % of UK households now own guinea pigs [ 5 ] . Statistically , this makes them the sixth most common pet species and more popular than all other rodent species . Recent advancements in the general understanding of the welfare needs of animals , possibly due to the introduction of the Animal Welfare Act 2006 , have led to a shift in how pets are viewed by their caregivers , with around 85 % of small pet owners stating that their pet is part of their family [ 6 ] . This may indicate a willingness to provide higher levels of care , reflective of the relationship owners have with their pets .
Around 15 years ago , the Rabbit Awareness Action Group ( RAAG ) was formed by a panel of experts to improve the welfare of pet rabbits in the UK through Rabbit Awareness Week ( RAW ). It has encouraged significant changes to rabbit husbandry through campaigns to promote responsible pet ownership and welfare-centred advice – for example , offering dietary guidance , which has reduced the number of rabbits being fed muesli-type diets from 49 % in 2011 to 18 % in 2020 [ 7 ] . In 2021 , an equivalent event for guinea pigs , Guinea Pig Awareness Week ( GPAW ) [ 8 ] , was launched to improve the health and welfare of guinea pigs .
The majority of disease processes seen in guinea pigs are understood to be related to poor husbandry or nutrition [ 9 ] . This , along with their rise in popularity , highlights the need for the veterinary profession to fully understand guinea pig welfare and help promote high standards of husbandry and care for these animals .
Nutrition
When considering how best to care for pet guinea pigs , it is important to examine the natural diet of their wild counterparts . As mentioned above , domesticated guinea pigs are believed to descend from wild cavies in South America , which generally inhabit open grassland , savannah and forests . They demonstrate crepuscular ( twilight ) feeding habits and eat a range of roughage , mainly in the form of grasses and leaves [ 4 ] .
Basic digestive physiology also provides a useful insight into the feeding requirements and dietary adaptations of cavies . In comparison to omnivorous Myomorpha rodents , cavies are a true herbivorous species with a high requirement for fibre . They routinely practise caecotrophy [ 10 ] , re-ingesting specialised soft faeces to extract additional nutritional value ( namely protein and vitamins ) from their relatively indigestible feed . They have a hindgut fermenter digestive system , meaning that they digest the majority of their food in the lower parts of the gastrointestinal ( GI ) tract , mainly the large intestine and the caecum , which contains microorganisms including bacteria and protozoa to aid the effective digestion of complex and fibrous carbohydrates such as grasses and hay [ 11 ] .
To maintain the health of the GI tract and its microorganisms , ad libitum ( unrestricted ) goodquality hay should be available to pet guinea pigs ( Figure 1 , page 44 ). The choice should be based on the hay ' s hygienic quality and nutritional quality , the former being of the greatest concern [ 12 ] . The hay should be clean , dry and free from contaminants , as the presence of mould and dust can contribute to respiratory problems [ 12 ] .
Volume 39 ( 5 ) • October 2024
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