By The Pawline veterinary teamVeterinary-reviewed by Alastair Greenway, BVM&S MRCVS · 9 August 2026
Reference range · pgDogs
22.329.6
Reference
22.3–29.6
Direction
Lower values are the concern.
This is the conventional reference interval. Your pet’s own report may print a slightly different range, so always read the value against that. Sign in to see your pet’s value on this strip.
Reticulocyte haemoglobin is the amount of haemoglobin loaded into the youngest red cells, so it reflects how much iron the marrow had available over the last few days rather than weeks ago. It falls before a conventional anaemia appears, which makes it an early read on iron-restricted red-cell production.
Most red-cell measurements describe cells that have been in circulation for weeks. MCV and MCH are averages across the whole population, so they change slowly — a problem that started a fortnight ago is diluted by millions of cells made before it began.
Reticulocyte haemoglobin looks at the other end of the pipeline. Reticulocytes are red cells released within roughly the last day or two, and measuring the haemoglobin inside them describes the iron supply the marrow is working with now (eClinpath).
Reticulocytes are the youngest red cells. The haemoglobin loaded into them reflects the iron the marrow had available in the last few days.
Reading a low result
A low value indicates red cells being built with too little haemoglobin — iron-restricted erythropoiesis. The classic cause is genuine iron deficiency, which in dogs and cats most often means chronic blood loss: gastrointestinal bleeding, heavy parasite burden, or repeated loss from any source (eClinpath).
Iron can also be present but unavailable. In chronic inflammation the body sequesters iron away from the marrow, and in chronic kidney disease reduced erythropoietin compounds it. In both, the marrow can be short of usable iron without the animal being short of iron overall.
The reason the test is interesting is timing: because it describes cells made in the last few days, it can fall while the haematocrit, MCV and MCH are all still comfortably normal. It is an early indicator rather than a confirmation.
Reading a normal result
A normal value suggests the marrow has had adequate iron available recently. That is genuinely reassuring about iron supply, but it says nothing about red-cell numbers — an animal can be anaemic for reasons that have nothing to do with iron, and the haematocrit and reticulocyte count answer that question instead.
What it is usually read with
It is most informative next to the reticulocyte count, which says how vigorously the marrow is responding, and the haematocrit, which says whether there is an anaemia to respond to. A regenerative anaemia with a falling reticulocyte haemoglobin points somewhere quite different from a regenerative anaemia with a normal one.
Cat vs dog
The measurement means the same thing in both species. Cats produce two forms of reticulocyte — aggregate and punctate — and only the aggregate form reflects recent production, which is one reason feline regenerative responses are read with more care than canine ones (eClinpath).
In chronic disease
This is where it is most useful. In chronic kidney disease and in ongoing low-grade blood loss, it can be followed over time as a read on whether the marrow's iron supply is improving or deteriorating — a question the haematocrit answers slowly and late.
Availability is the practical limitation: it is reported by some in-house and reference analysers and not others, so it may simply be absent from a panel.
Reference ranges reflect conventional laboratory intervals. Always interpret against your own lab's printed range and your veterinary surgeon's judgement. A brighter optimal band is shown only where a published guideline defines one, and it is cited.
This page is educational and is not a diagnosis. Lab results are interpreted in the full clinical context by your veterinary surgeon; a single value rarely tells the whole story.
