Feeding the Geriatric Horse

DG Pugh DVM, MS

Dipl ACT & ACVN

SouthernTraxx Veterinary Services

Pre-Geriatric Care

• Geriatric care should begin when horse is young …

• Healthier when young – more likely to be free of problems as ‘he’ ages

• Slow aging in many sp by restricting intake (?) (Ricklefs, 1995)

Equine Geriatric Care

• Geriatric horse is > 20 years ( > 17)

• ADR (Wt loss common in geriatrics)

• Proper health care will ‘usually’ enhance longer life span

Designed for the Individual

• Proper diet/BCS (protien,energy,minerals)

• Proper hoof care, (good Farrier)

• Parasite control designed for the individual

• Proper dental care (annually to bi-annually)

• Vaccination when not stressed

• Shelter that is free of `accidents

Geriatric Health Care

Biannual complete physical examination should be instituted….with close attention to BCS, hair coat, general health, teeth, eyes, locomotion

Blood work (CBC and Clinical biochemistries)

Specialized test (ACTH stimulation, fecal floatation, ophthalmic examination, etc) may be of great value in certain conditions

PREVENTION and VIGILANCE

Feed to Condition

• BCS System

• Forage Based Feeding

• Water

• Feed concentrates to balance the diet not as the primary component

Geriatric Diet

• Feed diet of 12-16% protein, 30-35% ADF• Mineral-salt mix (12-10% Ca, 10-8% P)• High quality forages• Geriatrics may have a decease in protein, fiber, &

phosphorus digestion and absorption (similar to horses with partial colon resection) (Ralston, Eq Vet Sci, 1989)

• Chronic parasitism => maldigestion/malabsorption (?) (Ralston, Eq Vet Sci, 2001)

Geriatric Horse Nutrition

• Senior feeds … supply specific nutrients (increase CP, increase fat, increase P, increase vitamins), easy to chew, palatable

• Fresh clean water that is `easy to get’

• Good quality mineral salt mixture fed free choice (Ca:P ratio of 1.5:1…~1% Ca & ~0.45-0.6 % P)

General Husbandry/Feeding

• Insure adequate feed intake as `pecking’ order changes (triangular spaced feed bunks,stall feeding,etc)

• Avoid dusty feeds

• Hazard-free shelter

• Avoid having to `work’ for feed and water if arthritis-lamness is a problem

Body Condition Score

• 1-3 extreme to moderate thinness

• 4-6 ideal

• 7-9 increasing stages of obesity

The Starving Horse

• Alabama Agroceriosis Syndrome• If BCS < 3 guarded prognosis for full recovery• Hypoproteinemia

• Parasites and poor quality hay

• Dental care– Older horses– Feed ~ 5 meals/day ( or more ?)– <0.5 % of ideal BW wt/ meal in conc……and up to

2.5% of ideal BW /day in forage based diet

Re-introduction to feed

• Refeeding syndrome• GRADUAL Change – watch concentrates• Good quality hay - alfalfa• Pelleted feeds at first• Do not carbohydrate overload• Monitor water intake• Free choice salt source

Appetite Stimulation

• Vary food – Lush (Sugars ??)

• Anabolic steroids

• Diazepam

• B-vitamins

Geriatric Diet• Probiotics of limited value….. have been

shown to aid in protein retention and digestion in young horses…..but not geriatrics…….still….?

• Do they even contain what they claim ? (Weese JAVMA 220, 2002)

Geriatric Diet

• Saccharomyces cerevisiae – may increase fiber digestion in young horses and pregnant or lactating mares, and may increase ‘N’ retention (Glade JAS 1986, Glade J Eq Vet Sci 1991, Glade Eq Nutri & Physiol 1989)

• Aspergillus oryzae – no improvement in

digestion… and might decrease fiber digestion (?) (McDaniel JAS 1993)

Geriatric Feeding

If BCS < 4, no existing disease, then …

Consider predigested or extruded feeding dietary ‘aids’ – cultures

Fat and fiber

Protein

• Lysine is the limiting AA in most horse diets, (threonine is second)

• Maintenance requirement – 7-9%

• Growth requirement 19% => 10%

Geriatric FeedingLoss of muscle mass in geriatrics Activity, protein absorption, ?

(Hintz, Proceed Cornell Nutri Conf, 1995)

In geriatric rats (?) suppl leucine may enhance muscle mass maintenance…

Alfalfa may be rich in leucine => might be benificial in preventing muscle loss ???? (Siciliano, Vet Clin NA, 2002)

Geriatric Horse Nutrition

• Low BCS – If physical examination is normal and no hepatic disease (serum chemistries) … vegetable oil or rice bran (high P and inappropriate Ca:P ratio)

Feeding Fat to Horses

• Most energy dense feed• Vegetable oil is a very palatable form of fat• Easily feed 30% of caloric intake as fat, if slowly

introduced• During low to moderate exercise, horses can mobilize

FA from adipose tissue => sparing glycogen => delaying fatigue

G Rich TAMU Eq Nutri Conf 2004

Fat Feeding

• Omega -3 fatty acids may enhance lipid metabolism and insulin sensitivity in animals.

• Corn oil contains no significant amounts of omega -3, whereas linseed oil (1-2 oz/day) may be good supplement

Omega-3 & Omega-6

Diets rich in omega-3 FA MAY block some parts of the inflammatory response

Horses fed a diet 10% in fat, had lower fibrinogen when fed soy oil vs corn oil (?)

Wilson et al, 18th Eq Nutri & Physio Symp, 2003

Geriatric Feeding

• If body condition is 4-5-6 (1-10 scale) then feed a good quality diet. (Tufts: 51% of their refereed geriatrics were fed senior horse diets)

Geriatric Feeding

• Immuno-suppression may be related to adrenal

tumors, protein malnutrition, mineral deficiency

• Geriatric’s may have a reduced response to Influenza vaccination (?)

Equine Geriatric Care• Geriatric horses have lowered BCS, depressed

immunity

• Geriatric’s may have a depressed T-cell function, & a reduced response to Influenza vaccination (?) (Horohov AJVR 1999)

• Age related immuno-suppression may be related to adrenal tumors, protein malnutrition, amino-acid imbalances, mineral deficiency, general poor health

Geriatric Medicine

• Colorado workers compared blood parameters of geriatric horses ( > 20 yrs) to young horses (< 5 years) and found only increased MCV (?) and decreased ascorbic acid in geriatrics

Geriatric FeedingVit C- Lower in geriatrics than younger horses… but

many had endocrine problems => stressed (Ralston AJVR 1988)

Suppl Vit C - Ascorbyl Palmitate is more effectively absorbed in horses (Snow Eq Nuti & Physiol 1987)

Equine Mineral

Good quality mineral salt mixture designed for your locale (12-10% Ca, 10-8% P, trace minerals…, 90 ppm Se, Cu as Cu sulfate, salt) offered free choice in normal animals.

Diet and the Hoof

• Feed a well balanced-good quality ration• Feed a good quality mineral-salt mixture free choice• Avoid dietary imbalances ( adding CHO’s to a well

formulated diet)• Offer supplements only as needed• Maintain a HEALTHY HORSE (proper deworming,

vaccination, hoof health, dental care, and general health care)

Geriatrics and Renal Disease

• Increased incidence of renal calculi in geriatrics when fed alfalfa

• If renal disease exists => decrease CP, Ca, P, K, increase calories

Geriatrics and Renal Disease

• Feed diet with 8-10% CP, vegetable oil (1-2 cups/day) supplemental B-Vitamins(Grass based, w/ corn, 2oz Linseed or Canola & Brewer’s yeast 2-4 oz/day)

Geriatrics with Hepatic Disease• Age related atrophy of rt liver lobe & compensated

hypertrophy of left lobe (Rooney, Eq Path, 1996)

• If serum chemistries suggest hepatic disease/damage….

- Avoid excess dietary fats and protein - Beet pulp (branched chain AA’s), Grass

Hays/grazing, frequent / small meals daily - Corn / Milo - Vit C, B vitamins

Geriatric Endocrine Disease

• Colorado workers showed an increase in pituitary adenomas (thyroid adenomas) in geriatrics

• Tufts workers showed greatest incidence of pituitary adenomas was in ponies, and horses > 30 yrs

Geriatrics with Pituitary Adenomas

• Avoid sweet feeds (molasis)

• Avoid forages harvested or grazed after being stressed (NSC <15%)

• For fall and spring pastures, graze in the early AM, and after hay feeding

• Soak lush hay for I hr prior to feeding

• If no hepatic damage, then feed E in form of fats and fiber

Geriatric Nutrition• Pituitary tumors – decrease responsiveness to

insulin along with increased susceptibility to laminitis……so avoid all founder causes

• If hepatic disease – 7-8% CP, no extra fat, supplemented Vitamin E (500 – 1000 IU/day)

• Multiple small meals of grass hay, oats, SBM, milo, corn

• If normal hepatic function 10-12% CP and 30% of energy from fats

Geriatrics and Colic

• Geriatrics may be prone to more choke and colic due to impactions (?)

• Auburn workers showed 88% of geriatric colics were impactions vs 29% of all aged horses.

• Tufts workers reported annual dental care was not as common in geriatrics as young.

dgpugh@southerntraxx.com

DG Pugh

SouthernTraxx Veterinary Services