Influence of lifetime food restriction on causes, time, and predictors of death in dogs

Abstract

D uring the 20th century, a large body of research evolved toward understanding aging and how aging can be influenced in individuals and in populations. A considerable portion of this effort has focused on elucidating roles of nutrition, including nutrient requirements during senescence, complications and treatment of chronic diseases, and preventive strategies to delay chronic disease and death. The association among energy intake, energy utilization, and aging is particularly interesting in this respect. The most wellknown intervention is long-term restricted food intake, which has a favorable influence on the life span of species as diverse as nematodes, spiders, rotifers, water fleas, fruit flies, fish, hamsters, mice, rats, and dogs. 1-3 Food restriction also modulates physiologic processes that may influence the expression of diseases that develop later in life. Results of studies 1-6 of rodents, dogs, and primates indicate that food restriction delays age-related death from species-, breed-, and strain-specific causes. Evaluation of lifetime food restriction in a population of dogs offered the opportunity to assess characteristics and predictive aspects of intrinsic (nonenvironmental, arising from inside the body 7,8) death in a large species that has a mean life span that lies intermediately between lower mammals, which have been studied extensively by use of food restriction models, and primates that presently are the subject of similar studies. 1,4-6 The purpose of the data reported here is to describe effects of lifetime food restriction on causes of death and associations among body composition and time of death in dogs. Overall life span data from this study have been previously reported. 2 Materials and Methods Dogs and housing-Forty-eight Labrador Retrievers from 7 litters were allocated to a paired-feeding study design. 9-11 Dogs were paired at 6 weeks of age by sex and body weight within litter and randomly allocated to either a control-fed or restrictedfed group. Dogs were housed in 2 X 19-m indoor-outdoor kennel runs with concrete floors. Free access to outdoors was available, and the activity level of the dogs was not restricted. All dogs were housed in the same environmental conditions for life, with no difference between feeding groups. Kennel assignment was maintained by original pairing, with either 2 (1 pair) or 4 (2 pairs) dogs/kennel. The study was approved by the supervising institutional animal care and use committee. Diets and feeding regimens-Control-fed and restrictedfed dogs ate the same nutritionally complete and balanced noncommercial formula; only the quantity of diet provided was different between feeding groups. 9-11 Beginning at 8 weeks of age, each restricted-fed pair mate was fed a quantity equal to 75% of the amount of food that was consumed on the previous day by the respective control-fed pair mate. When the dogs were 3.25 years old, 2 adjustments were incorporated into the feeding protocol. All dogs were switched from a growth formula containing 27% protein to an adult...

Lifespan and disease predispositions in the Irish Wolfhound: A review

“…This damage is thought to remain latent for some time, but eventually results in an earlier onset of aging and degenerative disease as well as increased rates of certain cancers. This theory is supported by the finding that adult giant breed dog cells have a lower proliferative capacity than those of other breeds (45), that large dogs tend to develop nonhereditary cataracts (thought to be due to accumulated oxidative damage) at an earlier age than small dogs (75), as well as the finding that dogs fed an energetically restricted diet tend to live longer than dogs fed a regular diet (38,43).…”

Caloric restriction

“…For example, it does not increase lifespan of house flies (Musca domestica) (Cooper et al, 2004) and in some rotifers and water striders it had a negative effect (Kirk, 2001;Kaitala, 1991). Among vertebrates CR was also shown to have beneficial effects on both median and maximal lifespan in mice (Mus musculus) (Weindruch, 1992), cows (Bos taurus) (Pinney et al, 1972) and dogs (Canis domesticus) (Lawler et al, 2008;Kealy et al, 2002;Lawler et al, 2005).…”

Aspectos nutricionais e ambientais da obesidade canina

“…A obesidade pode aumentar o risco de aparecimento de várias complicações (DIEZ & NGUYEN, 2006), tornando-se prejudicial à saúde do cão, e pode resultar em redução da sua qualidade de vida e da longevidade (MARKWELL et al, 1990;LAWLER et al, 2005). É uma enfermidade universal de prevalência crescente, sendo um dos principais problemas de saúde pública nos tempos atuais (MANCINI, 2001).…”