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LinespottingVet

Educational only. Not a veterinary prescription. Ask a vet before any treatment.

Research · sources

Grades, ages, and what opened on 6 October 2026

Evidence review for this site. Educational. Not a veterinary prescription. No doses. No page opened in the recheck carried a revision date after 6 October 2026.

How to read a grade

Evidence grades A to D
GradeMeaning
AConsensus guideline (SVA, ESCCAP, AAEP, AAHA, AHS, CAPC).
BLarge observational cohort.
CLab efficacy, case series, or model.
DNarrative, or a repeated number with a weak source.

The working claim

The review refuses, as a finding, the sentence that regular deworming doubles a dog’s life from about 8 years to about 14. The age band exists in the published mortality literature. A causal deworming trial does not.

BFor the shift in reported central estimates.DIf the sentence is used to mean “the wormer did it”.

The upper quartile (14.2), median survival (14.13) and median age at death (11.57) are not the same statistic. Breed and body size swamp protocol. Nutrition, vaccines, dentistry, surgery, housing and breed mix moved in the same decades. Nothing in these cohorts assigns the gain to anthelmintics.

Published ages, as written
EstimateFigureWhat it is
Patronek et al. 1997, US referral, 1980–19908.5 yearsMedian, crossbred. Purebreds in that caseload about 6.7. Cited by O’Neill 2013.
Proschowsky et al. 2003, Denmark10 / 11 yearsSurvey medians: 10 years purebred, 11 crossbred. Cited by O’Neill.
O’Neill et al., Vet J 201312.0 (IQR 8.9–14.2)Median. 5,095 deaths, VetCompass England. The upper quartile is the honest home of “14”, not the average. Leading causes: neoplasia, musculoskeletal, neurological.
Teng et al., Sci Rep 202211.23 yearsLife expectancy at age 0. 30,563 UK deaths, 2016 to mid-2020. Jack Russell 12.72. French bulldog 4.53.
Montoya et al., Front Vet Sci 202312.69 / 11.57 / 14.13Life expectancy at birth 12.69. Median age at death 11.57 (IQR 8.4–13.9). Median survival 14.13. Cats: 11.18 at birth. Obesity moved life expectancy by about a year. The paper does not mention parasites.
JAVMA 2024 methods commentary≥10 from 1997Earliest series about 8.5–8.6. From 1997 onward, medians at or above 10. Supports a rise. Refuses one cause. The article could not be read on 6 October 2026.

What parasite control can honestly claim

Dogs, where heartworm is endemic. Adult Dirofilaria immitis live in the pulmonary arteries and can kill. AHS and CAPC: year-round macrocyclic-lactone prevention plus annual testing, because adulticide treatment is risky. This is not the Swedish baseline.

C Resistance caveat, lab. Six monthly doses against the ZoeLA macrocyclic-lactone-resistant strain, Parasites & Vectors 2022: preventive efficacy 97.2 percent (moxidectin combination), 8.5 percent (ivermectin combination), 35.9 percent (milbemycin combination). “On a preventative” is not automatically “protected.” The article body was not re-read on 6 October 2026, so those percentages were not re-checked.

Puppies. Heavy Toxocara canis and hookworm burdens cause anaemia, poor growth and death. AAHA 2019: start as early as 2 weeks, every 2 weeks, until monthly control. That prevents puppy deaths. It is not a six-year extension at age twelve.

Cats. Kittens: milk-borne roundworm; the broader line is treat from about 3 weeks even if the first faecal is negative. SVA, last reviewed 20 May 2026, says four to six weeks, later than puppies, because infection is not before birth. That Swedish timing sits beside the “about 3 weeks” line. It does not replace it. Strictly indoor cats are not infected with roundworm. A 2015 Swedish study found roundworm in about 20 percent of outdoor cats. Feline heartworm: few worms, sudden death in a substantial minority of diagnosed cases, melarsomine is fatal to cats, so prevention is the only practical path where transmission exists. A topical combination was 100 percent preventive in two induced-infection studies. Efficacy, not lifespan.

Horses. Interval dosing drove Strongylus vulgaris out of well-managed yards. A 29-year necropsy series of young horses, whose page returned 403 on 6 October 2026, found that from about 2000, fatal Parascaris and cyathostomin infections replaced S. vulgaris and tapeworm deaths. Larval cyathostominosis still carries a high case fatality when it occurs, often cited as 40–70 percent (Corning 2009 via later reviews). AAEP, Merck and SVA: stop rotational 6–8 week dosing. Nielsen and colleagues, 2018, on US strongyle efficacy: macrocyclic lactones effective on 88.7 percent of operations; pyrimidine/benzimidazole on 21.4 percent. That article body was not read on 6 October 2026.

C UK infections model, 2025, preliminary. Current dog and cat parasite control estimated to avert about 5.5 million infections a year; full adherence about 9.3 million. Household vet costs avoided about £53 million now, about £95 million under the optimal scenario. Infections and invoices, not years of life.

Geography

Protocols, still with no milligrams

Dog. Puppy schedule from 2–3 weeks, as the guidelines describe it. Adult, low risk, Sweden: test, then treat what is shed. High risk or endemic travel: an ESCCAP frequency exists in the guideline, but this site does not quote one, because the file did not open, plus heartworm prevention only if the map requires it. Never dose horse paste.

Cat. Kitten schedule from about 3 weeks, with SVA’s four to six weeks beside it. Indoor adult: test, don’t automate. Hunter or raw-fed: regular roundworm and tapeworm control plus fleas (Dipylidium). No dog permethrin spot-ons.

Horse. Spring faecal on every adult, including large strongyle and tapeworm. Treat high shedders. The working bands under 200, 200–500 and over 500 eggs per gram are a yard convention, not a law. One to two strategic treatments a year for parasites egg counts miss. Foals: an ascarid plan that does not assume ivermectin still works. Faecal egg count reduction test every few years. Manure removal. No eight-weekly rotation. The vet writes the foal plan.

Natural products

D No guideline (AAEP, ESCCAP, CAPC, SVA) accepts pumpkin seed, herbs or diatomaceous earth as a substitute. Grade D as a control programme. Diatomaceous earth is a dust hazard. Essential oils and concentrated garlic harm animals, cats especially.

The 80 percent colic figure

D University extension pages, including Minnesota, say some studies tie about 80 percent of colic to parasites. That is not current colic epidemiology (impaction, displacement, sand, strangulation, enteritis and others). Do not put it in a client handout as fact. Parasites remain a real slice: tapeworm at the ileocaecal junction, S. vulgaris, larval cyathostominosis.

What this site does not publish

Every link in the review

Only addresses listed in the evidence review are linked. A source the 6 October 2026 check could not open is marked. Grades were not raised.