Veterinary nurses (VNs) play a vital role in educating clients on parasite control and pet nutrition. Many clients feel more comfortable discussing both parasite control and their pet's diet with a VN as they are perceived to be more approachable and may have more time to offer the client.
An increasing trend over the past decade across Europe has been the feeding of raw diets to domestic cats and dogs (Waters, 2017). In a recent survey (Pennelegion et al, 2020), 4% of UK cats and 10% of UK dogs were found to be fed raw meat. There are two types of raw feeding: homemade raw diets and commercially prepared raw diets. Owners who are feeding raw meat-based diets to their pets claim health benefits such as improved coat quality, wellbeing, immune status, and longevity (Morelli et al, 2019). These benefits are anecdotal and not currently supported by peer-reviewed scientific studies.
In contrast, health concerns with raw diets have focused largely on the spread of pathogenic bacteria, either directly from the diet itself or via the faeces of pets. Surveys in Europe and North America have consistently found Salmonella species in fresh-frozen commercial raw diets. There is a risk of introducing antimicrobial-resistant bacteria via raw diets, and raw pet food commonly exceeds hygiene thresholds for counts of Enterobacteriaceae (Davies et al, 2019). However, there has been less attention paid to parasites that may be spread via raw feeding and their zoonotic, animal health and economic impact. There are a number of parasites of veterinary and zoonotic concern that may be transmitted to pets via raw feeding.
Toxocara species
All puppies and kittens are infected with Toxocara canis and T. cati respectively, at, or shortly after birth (Overgaauw and Van Knapen, 2013). This occurs through transplacental (puppies) and transmammary (puppies and kittens) infection. It results in approximately 5–10% of adult domestic dogs and 10–26% of adult domestic cats shedding Toxocara eggs at any one time if left untreated (Overgaauw and Van Knapen, 2013; Wright et al, 2016).
The shed eggs are not immediately infective but contaminate the environment where they can develop to embryonated eggs. Once embryonated they represent a zoonotic risk that if ingested by humans can lead to visceral pain, lethargy, blindness and increased risks of chronic conditions such as asthma, epilepsy and dermatitis. Prevalence of egg shedding tends to be higher in dogs and cats that hunt or scavenge paratenic hosts such as birds, rabbits and rodents (Overgaauw and Van Knapen, 2013). Therefore when feeding raw meat and offal there is an increased risk of ova shedding in domestic cats and dogs which contaminates the immediate and wider environment. This will, in turn, increase the zoonotic risk.
Echinococcus granulosus and Taenia species
Tapeworms of dogs have a complex life cycle, requiring an intermediate host. The adult tapeworm is found in the intestine of the dog or cat. Eggs or proglottid segments containing eggs are passed in the faeces and ingested by the intermediate host. This leads to cyst formation in the tissues that are then infective if ingested by dogs. In the case of Taenia species and Echinococcus granulosus this occurs through the pet consuming raw meat and offal by scavenging, predation, or from raw diets.
Canine Taenia species tapeworms are found throughout the UK in lagomorph and livestock intermediate hosts. If infected dogs defecate on pasture or feedstores, livestock can become infected by ingesting tapeworm eggs and, sub-sequently, cysts forming in muscles and viscera. This can have considerable economic impact for farmers through meat and offal condemnation, especially in small holdings and island communities where infection and subsequent loss of income can be crippling. Infected dogs will also shed tapeworm segments. These proglottids are visible to clients and reduce the human–animal bond because of owner revulsion, providing another important reason for their control in first opinion practice.
E. granulosus has a similar life cycle to Taenia spp. tape-worms. Canids harbour small adult tapeworms (5–6 mm long) (Figure 1). Ruminants, pigs and human beings may all act as intermediate hosts with the formation of hydatid cysts. These can lead to offal condemnation in farm animals but, more seriously, can lead to significant pathology of cysts forming in the bone, lungs, liver, central nervous system and heart in humans. Ingestion of the cysts by canids occurs mostly through scavenging of carcasses or feeding on offal. Dogs fed diets containing raw offal containing hydatid cysts may go on to shed E. granulosus eggs in their faeces. These are immediately infective to humans. Hydatid cysts have been found in sheep and cattle offal throughout England and Wales, as well as in the long standing high prevalence foci in Powys, Herfordshire and the Western Isles of Scotland. It has been estimated that 1% of sheep offal and 0.5% of cattle offal is condemned annually as a result of hydatid disease (National Public Health Service for Wales, 2007).
Toxoplasma gondii
T. gondii has the potential to cause significant human and feline disease, particularly human birth defects and abortion. It is also the second most common cause of infectious ovine abortion. There is no effective preventative treatment or vaccine in cats, so hygiene and husbandry control measures form the basis of disease control.
Current evidence suggests that T. gondii infects all mammals but only felids act as a definitive host, producing oocysts in the intestine that are then passed in the faeces (Boothroyd, 2009). Although cats can be infected through faecal-oral ingestion of oocysts, they most commonly acquire the infection by ingestion of tissue cysts. This occurs through predation of intermediate hosts such as rodents and birds, and by feeding of raw meat. Cats ingesting T. gondii cysts in raw meat may shed oocysts representing a human health risk, particularly to the unborn babies of pregnant women who have not previously been exposed to infection. It has been a concern with the increasing trend of feeding raw meat-based diets, that raw-fed cats would have an increased incidence of oocyst shedding. Studies indicate that this is the case, putting owners of cats fed on raw diets at increased risk of exposure (Lopes et al, 2008; Freeman et al, 2013).
Neospora caninum and Sarcocystis species
N. caninum is closely related to T. gondii and prior to its initial recognition in 1984 and classification as a distinct genus and species in 1988, N. caninum infections were misdiagnosed as toxoplasmosis (Dubey and Schares, 2011). Since then, key differences have been identified between N. caninum and T. gondii in terms of their natural host range and definitive hosts. Canids act as definitive hosts for N. caninum and it is a significant veterinary pathogen. It is a cause of severe neuromuscular disease in dogs, and the most common cause of infectious abortion in cattle, leading to significant economic losses to beef and dairy farmers (Reichel et al, 2013). Unlike T. gondii it is not thought to pose a significant zoonotic risk. Although shedding of oocysts from infected dogs has been demonstrated to be low and infrequent, the occurrence of sporadic, clustered outbreaks of abortions in cattle suggest that oocyst exposure occurs and can be more significant as a cause of epidemic bovine abortion than previously thought (Dubey and Schares, 2006). Dogs are most commonly infected by consuming tissue cysts in bovine muscle, either through access to fallen carcasses or by feeding on raw meat as part of.
Sarcocystis cruzi is another protozoa of dogs and cattle with a similar life cycle to N. caninum. Dogs are infected through the consumption of raw meat and offal, with cattle subsequently becoming infected by ingesting oocysts passed in dog faeces. Meat and offal being condemned as a result of infection (Figure 2) can lead to significant economic losses for farmers in a similar way to that resulting from tapeworm cysts.
Preventing parasite transmission via raw meat consumption
Control of worm and protozoal infection through raw feeding is vital to reduce economic impact, improve pet health and reduce zoonotic risk. This requires a number of measures:
- Avoiding raw feeding — deliberate feeding of raw meat and offal is a significant route of protozoal transmission to cats and dogs, as well as tapeworm transmission to dogs. Avoiding raw feeding altogether would eliminate parasites being transmitted via this route.
- Pre-freezing of raw diet components — if raw diets are to be fed, however, freezing at -20*C for 1–2 days inactivates most parasite cysts in meat, thus minimising the risk of transmission. Processed complete raw diets are pre-frozen before sale to achieve this aim. A recent study of pre-frozen raw meat-based diets found 6% of them contained T. gondii cysts and 11% contained S. cruzi cysts (Van Bree et al, 2018). The viability of these cysts, however, was not assessed. There is no evidence that this pre-freezing has any impact on bacterial pathogens in raw diets.
- Regular worm treatment — cats and dogs fed raw meat or offal that has not been pre-frozen should be treated for Toxocara infection monthly with a licensed product to minimise zoonotic risk. In addition, dogs should be treated with praziquantel at least every 6 weeks to prevent proglottid shedding and minimise zoonotic risk from E. granulosus infection.
- Prevention of access of dogs to ruminant carcasses — this is still important to reduce the risk of tapeworm and protozoal infection in dogs, even if they are routinely fed a cooked diet. This includes raising awareness of the risks of these infections and encouraging dog owners to keep pets on leads around livestock pasture and feed stores.
- Anti-dog fouling campaigns — veterinary practices have an important role to play in supporting local councils in providing posters and literature to highlight the importance of responsible disposal of dog faeces. The practice of ‘stick and flicking’ does not reduce the risk of livestock exposure to any parasitic life stages which may be in the faeces.
- Good hygiene practice — hygiene is extremely important when handling raw meat and offal, and when handling faeces.
The role of the veterinary nurse
Providing nutritional advice is a key part of a VN's role. A range of suitable dietary options should be discussed, including raw diets, with the associated risks and benefits of each explained to enable clients to make informed decisions. As mentioned, the risks of feeding a raw diet are higher than those associated with commercial diets (parasitic and bacterial risk) and, therefore, warrant further discussion. Within veterinary literature there are many conflicting views and opinions surrounding raw diets (Davies et al, 2019), but what is clear is that those who do feed are passionate about the benefits. It is not necessarily the VN's role to change these views: instead their own beliefs should be put aside to enable constructive communication and creation of a suitable parasite control plan to minimise the risks for the pet and client. By working in partnership with the client and creating a relationship based on trust and honesty, compliance can be achieved/improved.
Recent survey work comparing attitudes between owners feeding raw meat-based diets and cooked diets supports the idea that those feeding raw meat-based diets are less engaged with health specialists (Morgan et al, 2017). In 2012, a study by Onepoll found 25% of pet-owning participants (2000) would welcome conversations on parasite control (Gerrard, 2016). Therefore, VNs should not assume an owner would not want to discuss the risks of raw feeding and subsequent parasite control.
The discussion on parasite control and raw diets may arise for several reasons: the owner is considering a raw diet and wants to be aware of any risks before doing so; the pet is already on a raw diet and the owner is aware there might be a risk; the owner and pet have attended routine parasite clinics/checks or other routine appointments.
It is important to always make time for clients who turn up at the practice or phone for information, whether this is at the time, or a later appointment/phone consultation is made — this conveys to the client that a VN is approachable and always available to help. Whether communicating over the phone or face to face, a VN must always ensure a personal approach is adopted. Phone calls should be handled professionally with front of house staff quickly and politely determining the reason for the call so they can be transferred to the most appropriate member of staff. Before any scheduled consultations, a VN should familiarise themselves with the patient's clinical history. This enables the client/pet to be greeted by name (and the pet to be made a fuss of) and the client will quickly feel at ease and develop a rapport with the VN.
Effective communication is the key to obtaining client compliance and this has many benefits for the pet, client, and veterinary practice/team. Through careful discussion and use of different communication methods the client obtains improved knowledge, in this case on the risks associated with raw diets and how to minimise them. This in turn improves the health and welfare for the pet and the client, as some parasites are zoonotic. It also benefits the wider pet/human population by reducing egg shedding into the environment. Compliance provides increased job satisfaction for a VN by knowing they have made a difference to pet and public health, and it strengthens the bond between client and practice.
Planning the consultation
There are several models of communication that can be referred to but the general principles are present in all. The sender, in this case the VN, delivers the information to the client; barriers to communication such as interruptions, noise, language or terminology can disrupt the message; the client receives and processes the information; and feed-back must be sought to ensure the information has been understood correctly.
Thought should be given to where the conversation takes place: taking the client into a dedicated nurse consultation room is preferable as this can be personalised with relevant posters and literature, but any consultation room or private space can be used. The room should be clean/presentable and well stocked with appropriate resources/teaching aids, such as models, diagrams and leaflets. Giving thought to the layout of the room particularly the table and chair(s) can improve communication. A table across the room in which the client and VN are either side or one sitting while the other stands could act as an unconscious barrier to communication. Noise should be kept to a minimum so muting any internal phones and putting an ‘in use’ sign on the door can help avoid unwelcome interruptions. As the consultations may take some time, good ventilation/temperature control and adequate lighting should also be considered (Ackerman, 2012).
There are several factors to consider when determining a personal consulting style (Table 1). The 7Cs can help the VN structure and plan a consultation while keeping the communication natural and clear.
Table 1. The 7Cs of communication
| C | Information |
|---|---|
| Complex | Keep it simple |
| Be aware of talking speed | |
| Consider language/accent barriers | |
| Avoid medical jargon and latin parasite names | |
| Content | Plan ahead |
| Consider the pitching level | |
| Context | Keep it relevant |
| Tailor to the individual | |
| Avoid distractions | |
| Courtesy | Consider facial expression and body language |
| Be respectful of the client's opinions | |
| Consistency | Standardise advice given |
| Demonstrate empathy/understanding |
Understanding client communication
Communication also needs to be an adaptive process in which the VN tailors their style to the individual client and their circumstances. There are three main learning styles — auditory, visual and kinaesthetic, or some may learn through a combination of styles. By using a variety of communication methods (verbal, leaflets, diagrams, videos and models) compliance can be improved.
Honey and Mumford (1986) expanded on this further describing four learning styles in greater detail:
- Activists — learn by doing, happy to jump in and enjoy new challenges
- Theorists — like to understand the theory/concept, need all the facts, analyse and theorize information given, need clear instructions without ambiguity
- Pragmatists — like to apply learning to the real world, need clear instructions, do not like hearing lots of theory
- Reflectors — learn through observation and reflection, like to think through the information rather than be rushed.
From this information it is clear some clients may easily reach a decision about which parasitic control methods will work for them and their pet but others may need time to reflect and discuss further with family members. The VN should remember this and not be disheartened if some leave a consultation without a firm plan in place, diarising a second appointment or telephone conversation would be beneficial to help clients reach decisions in a timescale with which they feel comfortable.
Communicating during the consultation
A natural start for a consultation is to determine/clarify the reason for the appointment and then obtain a relevant, detailed history. The VN should use a balanced questioning technique of both open and closed questions. By questioning in this manner, the VN can ensure all pertinent information is obtained regarding the pet's diet and parasite history, while allowing the client to feel they have been listened to and their opinions valued.
By then implementing active listening in which the VN repeats the client's answers back to them to ensure both parties have understood one another, a partnership can be created. Clients who feel they have contributed and been part of the decision-making process are more likely to comply with control measures recommended. The Cambridge-Calgary Consultation Model is recommended further reading (Ackerman, 2012).
The following are examples of questions that could be asked when considering parasitic risk associated with raw diets (it is not exhaustive):
- Is the client aware of the risks associated with raw diets? In this article we are specifically discussing the parasitic risks but it is also important to gauge knowledge on all risks, including bacterial pathogens. By asking this the VN can ascertain the client's current knowledge level and tailor further communication.
- What type of raw diet do they feed? Processed or unprocessed? Is the diet pre-frozen? As discussed, freezing at -20*C for 1–2 days inactivates most parasite cysts, thus minimising the risk of parasitic transmission.
- If a cooked diet is fed, is it supplemented by raw food? Some owners will feed a cooked diet but omit to mention that additional raw food is given. This may be deliberate or processed raw treats not considered to be ‘raw feeding’ and therefore not mentioned.
- Does the client use a parasite control plan? When was the pet last treated? And with what product? This enables the VN to determine when the pet can be treated next and with what product, this is important to avoid potential drug interactions.
- Has the pet had any previous reactions to treatment? These products should be avoided to improve compliance, if the client perceives the pet to have had a reaction following administration (e.g. hypersalivation following a spot-on formulation, vomiting following a tablet) they are less likely to continue with the control plan resulting in increased risk.
- What is the pet's normal lifestyle? Do they go swimming? Are they regularly bathed? Where do they go for walks? Do they walk in long grass/bracken or areas with livestock/deer? Questions of this nature help the VN determine the most suitable product. For example, efficacy of certain products can be affected by swimming/bathing which could lead to perceived poor efficacy and therefore poor compliance. Other lifestyle questions such as walking habits and geographical location can ascertain the other parasites the pet might be exposed to that need to be considered in the control plan.
- Does the client have children or grandchildren? Or is the pet in frequent contact with children? Is anyone in the household immunocompromised, elderly, pregnant or planning pregnancy? These groups are at increased risk of human toxocariasis, therefore a monthly anthelmintic should be recommended.
- Does the client have any other pets? All pets in the household should be treated, including indoor animals, as all animals within the home could transmit parasites.
The use of anthelmintics forms one part of the parasite control plan. It is important the VN also discusses other relevant control measures: hand hygiene regarding food preparation and handling of faeces, and regular poo picking. Clients should be educated on all factors to ensure a complete approach. It is crucial to accurately record details of conversations with owners and record details of recommendations in each patient's medical records. Clients should also be informed of practice policy regarding raw feeding and the nurse should advise the client accordingly in the event of their pet being admitted for treatment.
Conclusion
It is important to increase awareness of the potential zoonotic and pet health risks associated with the feeding of raw diets. From the perspective of reducing parasite transmission, raw diets should be avoided. Many owners are very committed to the idea of raw feeding however, and it is important to work with owners feeding raw diets to minimise infection risks. VNs are ideally placed in a position of knowledge and trust to work with owners to educate them regarding the risks. They can work with them constructively to ensure pets receive the nutrition they need while ensuring parasitic risk is kept to a minimum.
KEY POINTS
- Raw diets are increasingly popular as a feeding option for UK cats and dogs.
- A number of parasites of zoonotic and veterinary significance can be transmitted to cats and dogs through consumption of raw meat and offal.
- Education is vital in implementing steps to minimise transmission and subsequent disease risk from raw meat consumption.
- Veterinary nurses play an important role in educating clients and working with them to minimise parasite transmission from raw feeding.
- Effective communication with clients is imperative to achieve these aims.