Resting energy and species nutrient requirements

Resting energy requirement estimates daily energy use in a healthy, fed animal resting in a thermoneutral environment. RER is 70 × body weight in kilograms raised to 0.75, giving kcal/day. The original 1.5–2 × RER cue has no patient context. It is not an automatic feeding factor. Many inactive hospitalized or immediate postop patients need about RER. Daily needs vary with activity, life stage and disease. Follow body weight, body condition and muscle condition, then adjust the plan.

The protein comparison needs its units kept visible. The drawing says 3 g/kg for dogs and 5 g/kg for cats, but gives no time basis or clinical setting. Their exact provenance remains unresolved. These are original recall cues, not feeding targets. The book uses a metabolic-weight basis for its maintenance comparison. Those values cannot simply replace grams per kilogram. Check energy intake, protein quality, life stage and disease. Protein adequacy also depends on the endpoint: maintaining nitrogen balance and maintaining lean body mass are different questions.

The original fat cues are linoleic acid for dogs and arachidonic acid for cats. Cats also require linoleic acid, so the pair is not an exclusive list. Cats need dietary arachidonic acid; limited synthesis does not mean zero conversion in every tissue. Controlled deficiency studies show its role in feline reproduction. Both nutrients are fatty acids. The book’s “amino acid” wording for arachidonic acid is a typo.

References

Chris Wood’s drawing; Johnston & Tobias, 2nd ed., ch. 8; AAHA nutrition guidelines; Laflamme & Hannah 2013; MacDonald et al. 1983/1984.