feline paediatric medicine

F eline paediatric medicineKit Sturgess (1)

FECAVA SPONSERED PAPER

CLINICAL NUTRITIONIN KITTENSCats have unique nutritional needs. Nutritionalproblems are most likely to occur under periodsof maximum demand such as rapid growth,when any dietary deficiencies or toxicities can result in significantdisease. Key areas for consideration of nutrition include – Nutritional requirements of orphan kittens– Diets for growing kittens– Nutritional pitfalls

Nutritional requirements of orphaned kittensKittens can require supplementary feeding for a variety ofreasons, most commonly due to – Death of the queen during parturition– Failure of the queen’s milk supply – Rejection of one or more kittens by the queen – Litter size is too great for the queen to supply adequate

nutrition– Attempts to reduce the risk of infection from a queen known

to be FIV or FeLV positive Whilst the ideal substitute is to foster the kitten on to anotherlactating queen who will accept the kitten this is rarely possible.Queen’s milk is substantially different from bovidae milk (Table1) and this can not be used as a straight substitute. Home-madeand commercial formulae are available (Table 2 and 3).

Choice of supplement– An appropriate supplement should have

adequate nutritional density at therecommended dilution (Table 2); too lowand it is difficult for a kitten to take insufficient volume to meet its nutritionalneeds (stomach volume approximately70ml/kg).

– Hydration is important and concentrated formulae maypredispose to dehydration.

– Fluid requirements in neonatal kittens are up to 180ml/kg/dayhence frequent feeding is required to deliver an appropriatevolume of fluid.

S U M M A R Y

This article aims to look at three important areas of kitten medicine; nutrition, investigation of the stuntedkitten and managing the collapsed kitten. The latter two scenarios are common reasons for presenting a kittenfor further veterinary advice and investigation.

(1)Vet Freedom, Brockenhurst, Hampshire, GB - S042 7QT. E-Mail: [email protected]* Hosted by PSAVA(Poland)

This paper is based onthe FECAVA sponsored

lecture given at thePSAVA Annual

Congress* Krakow 19-20th

November 2005

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Queen Bitch Cow Goat

Dry Matter % 21 22.7 13 12Protein (%) 7.5 7.5 3.3 2.9Fat (%) 8.5 9.5 3.7 3.8Sugar (%) 4.0 3.8 5.0 4.7Ash (%) 0.6 1.2 0.7 0.8Calcium (mg/100g) 180 240 115 -Phosphorus (mg/100g) 162 180 95 -Iron (mg/100g) 0.35 0.7 0.2.-0.6 0.3-0.4Kcal/100ml 121 146 74

Table 1 – Comparison of queen’s milk with other milk sources

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– High osmolality fluids may delay gastric emptying e.g. KMRpowder.

– Arginine levels can be too low in some formulae andpredispose to cataracts (queen’s milk arginine = 430mg/100gor 355mg/100kcal).

– Taurine levels need to be sufficient (queen’s milk taurine =10mg/100g or 8.3mg/100kcal); if the taurine content isunknown, oral supplementation can be given (Figure 2).

– All home made recipes should be kept refrigerated and usedwithin 24 hours.

– Cream contains high levels of short and medium chain fattyacids and is relatively deficient in linoleic acid.

– Queen’s milk is high in albumin compared to casein;however, curd can be used as this contains coagulated caseinand not micelles (which are larger in bovine milk thanqueen’s milk and risks hard coagula forming in the stomach).

– Egg whites can cause diarrhoea but are a good source ofalbumin.

– Even the best replacers have potential problems so kittensshould be weaned as early as is practicable (from 3-4 weeks).

Feline paediatric medicine

Queen Recipe 1 Recipe 2 KMR powder* Cimicat* Vital Milkwww.aah-pets.com www.vetbed.co.uk Royal Canin

Dry Matter % 21 16.9 13.6 32.6 17.5 33.3Protein (%) 7.5 6.25 7.1 8.9 6.4 10.3 14.5 9.5 5.9 6.4 11 5.9Fat (%) 8.5 7.1 4.4 5.5 3.4 5.5 13.3 6.0 3.9 4.2 13 7Sugar (%) 4.0 3.3 4.7 5.9 2.9 4.7 6.8 (5.4) 4.5 (3.6) (5.6) (6.1) (6.2) (3.3)Ash (%) 0.6 0.5 0.8 1.0 0.7 1.1 2.1 1.2 1.0 1.1 2 1.1Calcium (mg/100g) 180 150 96.2 120 109 176 370 244 175 189 366 198Phosphorus (mg/100g) 162 135 126 158 109 176 290 192 131 141 266 144Iron (mg/100g) 0.35 0.29 0.6 0.75 3.5 5.6 1.3 0.8 NR NR NR NRKcal/100ml 121 80 62 151 92 186Volume (ml/100kcal) 83 125 161 66 108 54

Figures in italics are per 100kcal of metabolisable energy; figures in brackets are % lactulose; * - values are as fed according to manufacturers recommendations

Table 2 – Comparison of queen’s milk with milk replacers

* Protein supplement used was ProBalance Feline (available via www.calvetsupply.com ) – analysis - 47% crude protein, 1% crude fibre and 17% crude fat. The supplement has essential vitamins and minerals, additional nutrients and digestive enzymes.

Table 3 - Homemade milk substitutes for kittens

Recipe 2

One whole fresh egg 15gProtein supplement* 25gMilk, sweetened, condensed 17mlCorn oil 7mlWater 250ml

Total 310g

Recipe 1

Skimmed milk 70gLow fat curd (not cottage cheese) 15gLean minced beef 8gEgg yolk 3gVegetable oil 3gLactulose 0.8gVitamin/mineral mix 0.2gTotal 100g

Figure 2 – Echocardiogram of a cat with dilated cardiomyopathy.

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Feeding orphaned kittens

– Attention should be paid to the environment as kittens areunable to thermoregulate (ambient temperature 30-32oC;humidity 55-60%).

– Caloric need for kittens is 22-26kcal/100g (most kittens weigh100-120g at birth)– i.e. a new born kitten needs 18-23ml of queen’s milk per

day.– Weight gain of 10-15g/day is ideal.– Feed warm formula (37.8oC) at least 4 times daily depending

on the age of the kitten.– Under feed for first feeds gradually increase to full amount

over 2-3 days.– Feed using a nipple bottle, dosing syringe or stomach tube.– When using a nipple bottle, milk should slowly ooze from

the teat when the bottle is inverted. A drop of milk shouldbe on the teat before inserting into the kitten’s mouth. Themilk should be allowed to flow under gravity, squeezing thebottle to increase the flow rate risks aspiration.

– Feeding tubes are faster; a 5 FG tube should be used if thekitten is less than 300g. Measure from the nose to the last riband insert the tube to this length.

– After feeding it is vital to stimulate micturition and defecation,this can be done by massaging the anogenital area withmoistened cotton wool.

– Handling before feeding stimulates exercise promotingmuscular and circulatory development.

Diets for growing kittensOnce kittens have been weaned they need to be fed a dietsuitable for growth. A variety of proprietary diets are available.Kitten diets have higher energy density, protein and vitaminlevels than adult maintenance diets. They are usually designedfor kitten up until 6 months of age. There are a variety of reasonsfor making a dietary change at around 6 months as this oftencoincides with neutering that results in a 20-30% reduction incaloric need. When feeding or formulating a kitten diet, theunique nutritional requirements of cats should be born in mind.Kittens have a higher caloric need than adults although the totalvolume fed can be small (Table 4). 1. Cats have a higher protein requirement; arginine deficient

diets such as some baby foods can rapidly cause hepaticencephalopathy.

2. Cats have significantly lower (about 1/3rd the level) amylase

activity than dogs as well as lower levels of diassacharidasesmaking the feeding of a low fat diet more difficult in termsof an alternate source of calories.

3. Cats tend to be more selective eaters and therefore dietarymanipulation that results in reduced palatability such as theaddition of fibre can have a low acceptance.

4. Carbohydrates are not the major secretagogues of insulin incats.

5. Cats have an essential requirement for taurine. Taurinedeficiency is usually associated with attempts to feed avegetarian/vegan diet. Taurine deficiency can lead to centralretinal degeneration, dilated cardiomyopathy and reproductivefailure. In the early stages these changes are reversible.

6. Cats are more sensitive to oxidants in their food which cancause Heinz body anaemia. Such changes have beenassociated with feeding some baby foods which use onionpowder as a base.

7. Cats require a source of preformed vitamin A.8. Cats have an essential requirement for arachidonic acid in

their diet.

Vegetarian/vegan diets for kittens– It is not possible to formulate vegetarian/vegan diets for cats

without careful addition of essential ingredients that areusually animal derived such as taurine and arachidonic acid.

– Even when produced, balanced vegetarian/vegan diets donot seem to have the same health benefits as meat-baseddiets.

– Kittens are particularly vulnerable to nutritional deficiencies.

Feeding a raw meat dietIt has been argued that raw diets are better than cooked dietsfor cats. No good clinical studies have been performed to addressthis point. Even raw food is not the same as a freshly killedrodent or bird particularly as it is likely to have been refrigeratedor frozen. The greatest risk of feeding raw food is infectionwhether this is preformed toxins in spoiled foods, bacteria suchas Salmonella or parasites such as Toxoplasma. Appropriatesourcing, storage and preparation of raw food are crucial. Whenfeeding raw food, the possibility of cross contamination ofhuman food should also be considered.

Nutritional pitfallsBecause of their unique nutritional needs some foods are bestavoided or given in strict moderation to kittens, these include:

KIT STURGESS EJCAP - Vol. 16 - Issue 1 - April 2006

Physiological state Energy requirements Weight of food required g/kg body weight*(kcal / kg bodyweight) Canned diet Dry diet

< 3 months (growth) 250 * 190 603 - 6 months (growth) 130 * 100 306 - 12 months 80 (neutered) -100 (entire) ** 70-90 20-25

* based on typical kitten diet - canned (130kcal/100g); dry diet (425kcal/100g)** based on typical adult diet - canned (110kcal/100g); dry diet (400kcal/100g)

Table 4 - Estimated energy requirements in healthy kittens

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Table scrapsFeeding less than 10% of calories as table scraps is unlikely tocause nutritional imbalance but can lead to obesity if not takeninto account when calculating the daily ration. Feeding tablescraps can lead to behavioural problems - begging, refusing toeat regular food etc.

Meat and poultryCarnivores in the wild eat the majority of the carcase and notjust lean meat which has excessive amounts of phosphorusrelative to calcium and is deficient in sodium, iron, copper,iodine and vitamins. An all meat diet can lead to severe andpotentially fatal skeletal abnormalities, nutritional secondaryhyperparathyroidism (Figure 3) and joint malformations.

FishRaw fish can contain thiaminase which destroys vitamin B1(thiamine) as well as potentially containing parasites.Excessive amounts of fish can cause a relative deficiency ofvitamin E especially if the fish is packed in oil.Fish that has been improperly preserved or inadequatelyrefrigerated, particularly the tuna and mackerel family, can

contain preformed histamine. Ingestion results in reddening ofthe skin, most noticeably the nose, nausea, vomiting, diarrhoea,abdominal pain and pruritus that develops within 15-60 minutesof ingestion

LiverLiver contains excessively high levels of vitamin A leading topainful bone deformities which do not resolve even if the dietis corrected (Figure 4).

Milk productsCats generally do love milk but they may lack the enzymes todigest it resulting in large quantities of fermentable sugarsreaching the colon leading to osmotic diarrhoea.N.B. Milk is a balanced diet; calcium is NOT in excess hence milkcan not be used to balance diets which have excessivephosphorus such as an all meat diet.

Onion-based foodsCats are sensitive to oxidant intoxicants such as onions that areused as a base in some baby foods for example.

Pharmacological activitySome foods have pharmacological activity e.g. chocolate butthese are rarely consumed by kittens


Figure 5 – Severely stunted and septic kitten (on the table) causedby an umbilical infection. This kitten did not survive.

Figure 3- Radiograph showing a marked reduction in bone density in a kitten with nutritional secondary hyperparathyroidism associatedwith feeding an exclusive lean chicken diet.

Figure 4 – Radiograph of the stifle of a cat showing calcificationof the soft tissues associated with hypervitaminosis A.

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INVESTIGATION OF THESTUNTED KITTEN

Kittens are frequently presented to veterinary surgeons becausethey are poorly grown (Figure 5). Based on the DAMNIT-Vsystem, the most likely causes of stunted growth are highlighted.D Degenerative; developmental, demented (psychological)A Anomaly (congenital); allergic, autoimmuneM MetabolicN Neoplastic, nutritionalI Infectious; inflammatory; idiopathic; immune mediated;

iatrogenicT Traumatic, toxicityV Vascular

CausesAbnormality of bone growth– ChondrodystrophyDeficient nutrient intake– Inadequate or inappropriate diet– Gastrointestinal parasitism– Persistent vomiting or regurgitation e.g. vascular ring anomaly– Maldigestion / malabsorptionIncreased caloric demand– Fever– Chronic infectious or inflammatory disease (Figure 6)– Major trauma– Increased caloric loss– Protein losing enteropathy– Protein losing nephropathy– Urine nutrient loss e.g. juvenile onset diabetes mellitus, renal

glycosuriaMajor organ defect– Hepatic - portosystemic shunt, glycogen storage disease

(Figure 7) – Renal - dysplasia, pyelonephritis– Congenital cardiac anomaly– Lysosomal storage disease– Endocrinopathy

– Hypothyroidism (Figure 8)– Hyposomatotrophism

Key history– Did the queen have a normal, pregnancy and parturition?– When was the problem first noticed?– Has the kitten been slow and poorly grown since birth?

Suggests a congenital defect.– Was the kitten showing normal development (i.e.

indistinguishable from the other members of the litter) andthen suddenly stopped? Suggests an acquired disease.

– Are any other members of the litter similarly affected?– Have kittens in previous litters shown similar signs?– What is the kitten’s diet, appetite and food intake?– Are there signs, other than failure to grow, that indicates

major organ disease? – Is the kitten’s body proportionate or disproportionate?– Is the kitten’s body condition good or poor?


Physical examinationExamination of kittens can be difficult as they rarely stay still andcan be aggressive if from a feral background. Neonates tend toshow limited responses to disease, initially becoming agitatedand crying, progressing to inactivity, hypothermia and loss of thesuckling reflex. As with all young animals, changes in their statuscan be very rapid. Weight gain can be a sensitive indicator ofdeveloping problems and can be easily measured by the owner(Figure 9). Failure to gain weight over any 24 hour period isworthy of further investigation.

Figure 6 – An under grown kitten with an abscess on its headsecondary to feline infectious peritonitis.

Figure 7 – Six month old male, Havana kitten weighing less1.7kg and showing neurological signs associated with aportosystemic shunt.

Figure 8 – Hypothyroidism causing severe reduction in growthrate and skeletal malformation.

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External features– Body weight– Hair coat (amount, condition, parasites, persistence of kitten

coat)– State of hydration– Signs of injury– Appearance of umbilicus– Discharge from nose/eyes/ears– Urine staining (patent urachus)– Diarrhoea / rectal patency– Congenital malformation Eyes – Kitten’s eyes open between day 5 and day 14.– Pupillary light response is present within 24 hours of opening.– Mild cloudiness of cornea is usually evident at opening but

should resolve rapidly.– Swelling under the eyelids indicates pus formation (often

staphylococcus spp.), very rarely Chlamydophila felis(Chlamydia psittaci) (Figure 10).

Ears– External auditory meatus is closed at birth and opens between

6 and 14 days; check for mites.– Middle ear infection indicated by a bulging tympanum.Mouth – Colour of mucous membrane.– Evidence of cleft palate (Figure 11).

Thorax – Shape of thorax - flat chest (Figure 12), pectus excavatum– Heart rate around 200-220 beats per minute.

– Respiration 15-35 per minute.– Regular rhythm.– Heart murmurs may be innocent, associated with non-cardiac

disease (e.g. anaemia, portosystemic shunt) or associatedwith congenital cardiac disease (Table 5).

– Lung sounds difficult to distinguish but should be present;check for symmetry or malformation of the thoracic cavity.

Abdomen – Should feel full but not swollen or tight.– Liver and spleen not palpable.– Intestines soft, mobile and non-painful.– Urinary bladder freely movable.


Daily weight of kittens

Wei

ght (

gram

s)

Age (days)

FCK

Figure 9 – Growth curves for a litter of kittens, one kitten’s growth rate began to slow. A few days later this kitten developed a flat chest (Figure 12).

Figure 10 – Kitten with serous ocular discharge associated withC.felis infection.

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Neurological assessment – Alertness– Response to stimulation– Suckle reflex– Other reflexes appropriate to age– Gait (walking from around 4 weeks old)– Posture– Flexor and extensor dominance appears more variable in

kittens than puppies.

Decision making– Is the nutritional and caloric intake adequate?– Is trauma a realistic possibility – if so how is it affecting

growth?– Is the problem likely to be a congenital abnormality (if so

which organ) or an acquired disease?– Is an endocrinopathy likely – kittens tend to be stunted but

otherwise clinically well?

– Acquired diseases tend to be infectious or toxic and thereforeother members of the litter are likely to be showing signs.

Diagnostic approach– Ensure adequate and appropriate nutrition.– Ensure adequate worming and ectoparasite control.– Haematology, biochemistry and urinalysis to assess major

organ disease– Include hepatic function tests (bile acids).

– Retrovirus serology.– Survey radiographs - thorax, abdomen, and appendicular

skeleton.– Ultrasound and echocardiography– Hormonal tests – growth hormone, thyroid function– Endoscopy and biopsy of the stomach and small intestine.– Fibroblast culture or urinalysis for lysosomal storage disease

(Figure 13). – Specific DNA-based genetic tests.


Figure 11 – Cleft palate. Figure 12 – Flat-chested kitten – this condition develops shortly after birth and particularlyaffects Burmese kittens.

Innocent murmurs Congenital murmur

Usually I-III/VI, craniodorsal, ejection type Usually loud unlessVariable with heart rate and body position – large defectOften musical – tricuspid valve dysplasia Typically diminishing with age & resolving by 16 weeks – mild semilunar valve stenosis

May be associated with clinical signs– failure to grow– cyanosis, – exhaustion after brief periods of play– weakness– collapse– Source of congenital murmurs can be difficult to identify

in some cats

Table 5 – Characteristics of innocent cardiac murmurs and murmurs associated with congenital heart disease

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History should be focused on– Health of other members of the litter – infectious disease is

likely to affect more than one kitten in the litter.– Environment to assess the likelihood of trauma or access to

potentially toxic compounds.– Internal or external parasitism is very common.

– What parasite control has been used?– Is there a possibility that the parasiticide is causing the

problem e.g. piperazine, organophosphates, permethrins?

Physical examinationA thorough physical examination is essential both in order totry and achieve a diagnosis as well as identify urgent problemsthat require therapy. Normal physiological values for kittens aregiven in Table 6.

Investigation of neonatal disease– Routine haematology (Table 7) and biochemistry (Table 8)

can be performed from a very early age on blood obtainedby jugular puncture (Figure 14).


MANAGING THE COLLAPSEDKITTEN

Neonatal responses are relatively limited and body reserves arelow so kittens can rapidly change from being bright and wellto collapsed and seriously ill. This section will focus on theinitial management of the collapsed kitten including physicalexamination, history taking, basic diagnostics and rationaltherapy.

HistoryMany of the historical questions will be similar to those for thestunted kitten. Congenital diseases can present acutely such asthe kitten with a cardiac defect that goes into congestive heartfailure or the kitten with a portosystemic shunt that becomesencephalopathic. However, in the majority of cases, trauma,intoxication or infectious disease will be the most likely causes.In such cases, the kitten will have been normally developed,growing and eating well up until the very recent past.

Age Rectal Heart rate Respiratory Environmental(days) temperature (bpm) rate (/min) temperature

(oF) (oF)

0-7 96 ± 1.5 200-250 15-35 85-908-14 100 70-220 15-35 8015-28 - 70-220 15-35 8029-35 Adult 70-220 15-35 70-75>35 Adult 70-220 Adult 70

Table 6 - Physiological values in young kittens

Parameter Kittens (mean or range)

Age 0-3 days 2 weeks 4 weeks 6 weeks

PCV (%) 41.7 33.6-37.0 25.7-27.3 26.2-27.9Haemoglobin (g/dl) 11.3 11.5-12.7 8.5-8.9 8.3-8.9RBC (x1012/l) 5.11 5.05-5.53 4.57-4.77 5.66-6.12MCV (fl) 81.6 65.5-69.3 52.7-55.1 44.3-46.9MCH (pg) 24.6 22.4-23.6 18.0-19.6 14.2-15.4MCHC (g/dl) 27.3 33.7-35.3 32.5-33.5 31.3-32.5WBC (x109/l) 7.55 9.1-10.2 14.1-16.5 16.1-18.8

Table 7 - Haematological values in young kittens

ParameterKitten age (weeks) 2 4 7-12

Total protein (g/l) 40-52 46-52 51-57Albumin (g/l) 20-24 22-24 24-32Sodium (mmol/l) - 149-153 147-152Potassium (mmol/l) - 4.0-4.8 5.0-6.2Chloride (mmol/l) - 120-124 113-128Inorganic phosphate (mmol/l) - 2.0-2.4 2.5-3.1Calcium (mmol/l) - 2.4-3.2 2.2-2.8Urea (mmol/l) <5 <5 4.2-6.3Creatinine (µmol/l) - 36-54 36-91Cholesterol (mmol/l) 4.3-11.6 4.6-11.4 -ALK-P (U/l) 68-269 90-135 -ALT(U/l) 11-24 14-26 -Glucose (mmol/l) 6.08-10.32 7.92-8.96 -Bilirubin (µmol/l) 1.7-16.9 1.7-3.4 -Bile acids (µmol/l) <10 <10 -

Table 8 - Serum biochemistry values in young kittens

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– Many infectious diseases develop too rapidly to obtain resultsquickly enough (especially bacterial culture and sensitivity orpaired serum samples) to be of value to that individual buta knowledge of cause may be beneficial to the rest of the litteror subsequent litters.

– To minimise the amount of blood required, glucose can beestimated on a glucometer and 0.5ml EDTA tubes usedmaking a total bleed of 1.5ml in the smallest of kittenssufficient for most tests to be carried out.

Blood volume in cats is estimated at 75ml/kg. A week-oldkitten will weigh around 200g and have 15ml of blood

– Radiographs can be difficult to evaluate in young kittens asmineralization of the skeleton is poor and the film can beeasily over exposed. Reducing the kV to half that used foran adult of similar body thickness should produceradiographs that will provide valuable diagnostic information.

– Faecal examinations can be easily performed and are ofparticular value where protozoan parasites are suspected.

Despite aggressive therapy, acutely sick kittens will die and itis important to try and encourage the owner to allow a postmortem examination. Maximum information can be obtained ifthe carcass is fresh. If a post-mortem can not immediately beperformed, the body should be stored in the fridge and not thefreezer. A systematic approach should be adopted and all detailsshould be recorded including sex, colour, body weight, amountof body fat, presence of ingesta in the stomach, faeces in thecolon and urine in the bladder.

Consideration affecting the treatment of neonatal diseaseSpecial consideration needs to be given when giving drugs orfluids to paediatric patients as they have an immaturemetabolism, small total body weight but relatively high bodysurface area.

Drugs– Absorption, distribution, metabolism and excretion of drugs

can be significantly different from adults.– Few drugs have had dose rates calculated for use in young

kittens.– Generally, an increase in the initial dose (/kg) is required with

a lengthening of the interval between doses.– Great care should be taken when administering broad-

spectrum antimicrobials orally because of their potentiallyadverse effects on the developing gut microflora.

– Subcutaneous and intramuscular absorption of drugs is slowerand less reliable than in adults particularly if the kitten isdehydrated.

– Antimicrobials administered to the dam do not reachtherapeutic concentrations in the milk.

– Ensuring adequate nutritional support either by naso-oesophageal or gastric intubation is a vital part of therapyparticularly in the face of sepsis.


Figure 13 – An under grown kitten with skeletal abnormalitiesassociated with a lysosomal storage disease.

Figure 14 – Jugular venipuncture in a week old kitten.

Figure 15 – Fluid warmer that can be attached to the giving setline.

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Fluid therapyFluid requirements (/kg) are higher in neonates than adults BUTtotal volumes are low. Young kittens have immature kidneys andlack the ability to concentrate their urine in the face ofdehydration and therefore will become dehydrated very quicklyespecially if there is increased fluid loss such as vomiting ordiarrhoea.– Maintenance fluid requirements of very young kittens (less

than 2 weeks) are around 180ml/kg/day. By weaning fluidrequirements are around 120ml/kg/day. Adult maintenancerequirements (50ml/kg/day) are appropriate in kittens over6 months old.

ExampleA week old kitten weighing 200g will therefore require 36mlof fluid at maintenance over 24 hours i.e. 1.5ml per hour.Even using a paediatric giving set, this is equivalent to 1 dropevery 40 seconds.Increased fluid rates are necessary if the kitten is dehydratedor has increased fluid loss (diarrhoea or vomiting). Fluidshould be given at approximately 4ml/kg per episode ofvomiting or diarrhoea

If the kitten is 8% dehydrated and having episodes ofvomiting and diarrhoea every 4 hours then–Maintenance at 1.5ml/hr

Fluid deficit is 16ml – replace 50% in the first 6 hours (=1.3ml/hr) and the remainder over 18 hours (= 0.5 ml/hr)

– Increased need associated with GIT signs is 24ml/kg/day= 5ml/day = 0.2ml/hrFluid rate for first 6 hours is then 3ml/hour (1 drop per 20seconds) reducing to 2.2ml/hour (1 drop every 27 seconds)

These calculations are approximations and it is vitalthat the state of hydration and urine output ismonitored.

– Syringe pumps can be of great value and are significantlycheaper than fluid pumps; otherwise a burette with apaediatric giving set (60 drops per ml) will ensure that thekitten is not over-hydrated.

– Kittens will tend to become acidotic associated with manydisease states but reduced hepatic function can mean thatthey are less able to metabolise lactate into bicarbonate. – For most kittens Ringers solution is appropriate. If the

kitten is significantly acidotic, bicarbonate can be givenseparately at 1mmol/kg over 20 minutes.

– Glucose can be replaced using a 5% dextrose solution mixed50:50 with lactated ringers or by giving 1-2ml of 10-25%glucose i/v to profoundly depressed kittens.

Methods of drug and fluid administrationKittens are particularly prone to hypothermia so fluids shouldbe warmed before administration. Because the rate ofadministration of fluids is slow, warming the whole bag of fluidis not effective. Fluid needs to be warmed as it passes throughthe giving set using a proprietary fluid warmer (Figure 15),heated pads or warm water that is regularly replaced.

Intravenous – 23g or 25g catheter can be placed in the cephalic vein of

many small kittens.– Larger catheters can be placed in the jugular vein but this can

be difficult in kittens that are dehydrated. Placing a jugularcatheter may required sedation/anaesthesia and cut down.The benefits of jugular access have to be balanced with therisks of placement.

– The kitten’s short legs can make the catheter very positionaland flow difficult to maintain in gravity fed fluid systems.Forced flow in the absence of syringe or fluid pumps can beachieved using – Battery operated, fixed-rate (0.5 or 1.0ml/hr), single use

fluid reservoirs (Figure 16). – Spring-driven, refillable, syringe pumps, flow rate variation

is limited and achieved using variable diameter tubingconnected to the patient.

– Single patient use, refillable balloon infusion devices thatuse the elastic recoil of the balloon to push the fluid. Flowrate variation is limited and achieved using variablediameter tubing connected to the patient.

Intraperitoneal – This route is not ideal as absorption can be relatively slow

especially in the face of hypovolaemia and is poorly suitedto long-term fluid therapy. However, in the hypovolaemic,collapsed kitten this may be the fastest way of deliveringtherapy in the short term.

– The risks of puncturing viscera are low.– Aseptic technique is mandatory. – Daily fluid requirements should be calculated and the volume

divided to be given 2-3 times daily.

Intraosseus– Useful where venous access not possible due to vein size or

hypotension causing the veins to collapse.– The cortical bone is sufficiently soft in kittens such that a

hypodermic needle (18-19g) can be used.– The area should be surgically prepared and the needle placed

in either the proximal tibia or proximal femur. Only oneattempt should be made at each site since, if the bone cortex

Figure 16 – Mechanical, lowflow rate devices (availablefrom Mila International:www.milaint.com).

93


is already punctured, it will result in fluid leaking out.– Fluids, drugs or whole blood can be given at the same rates

as for i/v therapy.

Neonatal isoerythrolysisBlood group A kittens are at risk of neonatal isoerythrolysis ifthey are born to a B group queen. B group cats have naturallyoccurring, high affinity, anti-A antibodies that are passed to thekitten in the colostrum resulting in immune-mediated haemolyticanaemia.

Clinical signsKittens start to fade when they are a few days of age. Ownersfirst notice discoloration of the urine due to haemoglobinuria.Kittens will become jaundiced. Tail and ear tip necrosis will alsooccur.

Blood group distribution by breed in the UKNB – blood group distribution in other areas of Europe may bedifferent from thisBreeds with no type B cats– Siamese, Burmese, Tonkinese, Oriental short hair, OcicatBreeds with <5% type B cats– DSH, DLH, Maine Coon, Norwegian Forest CatBreeds with 10-20% type B cats– Abyssinian, Birman, Himalayan/Persians, Scottish fold ear,

Somali, SphinxBreeds with >20% type B cats– British and exotic short hairs, Cornish and Devon rex

TherapyAggressive therapy needs to be given at an early stage and bloodtransfusion with group A blood is necessary. Mortality rates canbe high.

PreventionSubsequent matings of the queen should with a B group studcat. If this is not possible then the kittens should be bloodgrouped (jugular sample or umbilical blood) at birth before theyare allowed to suckle and A or AB group kittens given A groupcolostrum (usually requires fostering onto an A group queen)or milk replacer until after gut closure (24 hours). In kittensgiven milk replacer, the lack of colostrum will, however, makethem vulnerable to other infectious diseases. This risk can bereduced by feeding 1-3ml of serum from a type A cat.Ideally queens and stud cats should be blood typed prior tomating.

Fading kittensDefinitionThese are typically kittens born apparently healthy that eitherfail to suckle (or lose their suckle reflex) and die with no organ-specific clinical signs. Fading kittens may occur as single cases;affect multiple or all kittens in the litter.

Common causes– Congenital abnormality– Exposure to teratogens in utero– Inadequate nutrition

– Inadequate colostrum– Low birth weight– Trauma– Neonatal isoerythrolysis– Infectious disease

Key history– Breeding history of household.– Disease status of household.– Individual breeding history of queen.– Number of kittens born alive and dead.– Health of queen now and during pregnancy.– Status of other litter members.– Status of other kittens in the household.– Recent arrivals / showing / mating.– Pattern of illness to-date.– Health parameters noted by breeder e.g. weight gain.– Hygiene, worming, vaccination and flea control regimes.– Has the kitten ever appeared normal?– Did the kitten ever suckle normally?– Has supplementary feeding been provided (risk aspiration)?– Blood group of queen and stud cat (if known).

InvestigationA full physical examination should be performed including aneurologic assessment for alertness, suckle reflex, response tonoxious stimuli and reflex responses (not fully developed until12 weeks).

Decision making– Level of problem - household, litter or individual.– Congenital vs. hereditary?– Infectious vs. anatomic?– Likelihood of trauma?– Possibility of neonatal isoerythrolysis?

Diagnostic investigation– Routine haematology and biochemistry– Faecal and urinalysis– Bacterial culture– Serology

– A positive FIV test can not be interpreted in a neonatebecause of passive transfer of antibodies from the queen.A kitten born to an FIV antibody negative queen is highlyunlikely to have FIV.

– Imaging studies– Biopsy / post mortem

Blood transfusionsKittens can survive with a very low haematocrit and can presentwith a PCV as low as 6-8%. These kittens are very vulnerable tostress and need to be handled carefully and pre-oxygenatedbefore attempting to take blood or place an i/v line. Wheresevere anaemia is suspected, a small amount of blood is requiredto blood type the kitten and measure their PCV. If the kitten issymptomatic or has a PCV of less than 12%, blood transfusionis appropriate and can be very rewarding. Only small volumesof blood are required but can result in dramatic clinicalimprovement.

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Blood volume required

Blood collectionBlood can be collected in 10-20ml syringes pre wetted with acidcitrate dextrose solution (1ml/10ml of blood collected) via a 21gbutterfly catheter placed in the jugular vein of a donor cat. Insome cases mild sedation of the donor [e.g. ketamine (5mg/kg)and midazolam (0.25mg/kg)] may be necessary. Alpha2-adrenergic agonists such as medetomidine should be avoideddue to their hypotensive effects making venipuncture difficult.Donor cats should be clinically healthy, less than 8 years old andideally have been tested negative for FeLV, FIV and FIA (felineinfectious anaemia).

Performing the transfusionBlood should be administered via an intravenous or intraosseusroute using a T-connector or low volume extension tubing (2-3ml) to minimise dead space. Blood should be given at an initialtransfusion rate of half maintenance for the first half hour in thenon-emergency situation. In reality, for most kittens this meansa bolus of 0.5 ml and waiting for half an hour to see whetherthere is an adverse reaction. Thereafter blood can be given attwice maintenance. In an emergency, blood can be given atshock rates (70ml/kg/hour) – for the kitten in the exampleabove, this means giving the 11ml needed over about 45minutes.

CONCLUSIONSKitten medicine is a truly challenging but very rewarding areafor the veterinarian. The small size of the patient, speed withwhich they deteriorate and lack of localising clinical signs makesinvestigation and treatment difficult. The value of success,however, is great in the hope that your patient will survive andenjoy the next 15 year or so of life.

ACKNOWLEDGMENTSProfessor T.J. Gruffydd-Jones for Figures 8 and 11Dr D. Gunn-Moore for Figures 6 and 13Mrs R. Giles for Figure 1

REFERENCES AND FURTHERREADINGHOSGOOD (G.), HOSKINS (J.D.) (1998) - Small Animal Paediatric

Medicine and Surgery, Butterworth Heinemann, Oxford.IHLE (S.L.) (2005) - Failure to Grow in Textbook of Veterinary

Internal Medicine [6th edition]; Ettinger, S.J. & Feldman, E.C. eds.Elsevier Saunders, Missouri, pg. 80-82.

JACOBS (R.N.), PAPICH (M.G.) (2000) - in Kirk’s Current VeterinaryTherapy XIII; Bonugura, J. ed. W.B.Saunders, Philadelphia, pg.1211-1212.

KIRK (C.A.), DEBRAEKELEER, (J.), ARMSTRONG (P.J.) (2000) -Normal Cats in Small Animal Clinical Nutrition [4th edition];Hand, M.S., Thatcher, C.D., Remillard, R.L. & Roudebush, P. eds.Walsworth Publishing Company, Missouri, pg. 329-334.

STURGESS (C.P.) - (1998) Infectious Disease Of Neonates, YoungPuppies & Kittens in BSAVA Manual of Small AnimalReproduction & Periparturient Care, pg.159-166.

STURGESS (C.P.) (2003) - Feline Internal Medicine, Blackwells,Oxford, pg 27-28, 35-36, 313-319.

ExampleA 200g kitten (7 day old) presents with a PCV of 8%.A group matched blood donor is available whose PCV is 30%.Target PCV is 25% for the kittenVolume required = Desired PCV (L/L) – Actual PCV (L/L) x 100 x bodyweight (kg)

PCV of donor (L/L)

= 0.25 – 0.08 x 100 x 0.2 = 11ml0.30

feline paediatric medicine

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