Medically reviewed by Healthline Medical Team on March 12, Scientists have already noted a lack of genetic diversity in commercial chickens , making them more susceptible to disease. The luteal phase of the menstrual cycle begins right after ovulation and involves the following processes:. Now please check your email to confirm your subscription. This page was printed from:
Some manufacturers sell frozen raw diets and premix products to cater to owners who feed raw. Fat may then be sprayed on the food to increase palatability , and other minor ingredients, such as heat-sensitive vitamins, which would be destroyed in the extrusion process, may be added. Dry food is most often packed in multi-wall paper bags , sometimes with a plastic film layer; similar bag styles with film laminates or coextrusions are also used.
It is also sold in foil pouch form. Even though cats are obligate carnivores , there are vegetarian and vegan cat foods available. Vegetarian cat food must be fortified with nutrients such as taurine and arachidonic acid that cats cannot synthesize from plant materials. Low protein diets are not as popular with consumers [ do you mean cats or their owners? Raw feeding is providing uncooked ingredients to cats. Firm believers in raw diets report that they bring health benefits such as a shiny coat, cleaner teeth, improved immunity, energy and body odors [ why is body odour a health benefit?
Commercial raw diets can undergo High Pressure Pasteurization HPP , a process which kills bacteria and pathogens, including salmonella , using high water pressure. Weight control simply means ensuring an energy balance: Weight gain means more energy is being consumed than is being expended in exercise and other functions. A weight management diet is designed to allow fewer calories to be consumed in a larger volume of food, allowing for less risk of an energy imbalance.
But the cat needs to take enough exercise too. Adult cats should be fed a diet that has been formulated for maintenance [ clarification needed ] , while at the same time it should be fed according to preference [ whose?
Cats generally prefer to eat smaller meals more frequently, which tends to lead to less weight gain compared to cats that are fed free-choice food. Meanwhile, some cats adapt to free-choice feeding and can maintain normal body weight, with no weight gain.
For indoor cats, there are a variety of choices to promote exercise, including various cat toys designed to stimulate chase and play behaviours. Many pet cats are fed energy-dense, high carbohydrate diets, which provide much more energy than needed.
This is a major issue with indoor cats as it has been shown to lead to obesity. To prevent cats from becoming overweight, owners should be more inclined to implement weight control diets, which provide the cat with nutrient-dense, low energy ingredients. Along with energy input and output, specific nutrients can be important in weight control diets. Fiber is one important component in weight control, with various benefits. A source of soluble and fermentable fiber helps to increase the movement of digesta through the gut and decrease gastric emptying.
This helps to increase satiety in cats, potentially decreasing feeding rates and voluntary energy consumption. Prebiotic fibers like fructooligosaccharides FOS and mannonoligosaccharides MOS decrease the number of pathogenic bacteria and increase the number of beneficial bacteria in the gut. They also help to maintain microbial balance and a healthy immune system. Fiber is fermented in the colon to produce short-chain fatty acids which can be used as an energy source. Fermentable fiber has been demonstrated to enhance general health and decrease inflammation.
Insoluble fiber has been proposed to regulate appetite by releasing hormones that reduce hunger. Sources of fiber commonly added in weight management cat food include beet pulp, barley, psyllium and cellulose.
Another nutrient important for weight control diets is protein and its component amino acids. Felines, being obligate carnivores, require a natural diet of strict [ clarification needed ] animal products which consists of protein and fat i.
Dietary protein supplies amino acids that can be utilized and metabolised as energy over [ clarification needed ] fat when provided, even though protein is not stored in the body the same way as fat. Lean body mass maintenance is regulated by protein intake, but more importantly is regulated by exercise.
Limited protein and amino acids in the diet will limit lean body mass growth, but exercise or lack of exercise will allow growth or shrinking of muscle. Successful weight control involves maintenance of healthy adipose tissue levels, but most importantly maintenance of lean body mass.
Lean muscle is the driver of basal energy metabolism and aids in the use of energy. When sufficient levels of fat are provided, fat will be used by the body as an energy source, but only when there are insufficient levels of protein. This is a vitamin-like substance that is found in animal protein, and is the only form [ of what? L-carnitine is involved in many biological pathways, more specifically fatty acid metabolism, allowing for the conversion of long-chain fatty acids into energy.
The introduction of L-carnitine ensures rapid transport and oxidation of fatty acids as well as efficient usage of dietary fatty acids and protein. Supplementary L-carnitine is used more often in weight loss diets, since its benefits mainly involve fatty acid metabolism to control weight loss. However, since weight control is, in essence, a prevention stage in overall weight management, it still has value in weight control diets in preserving and building lean body mass and inhibiting the storage of excess dietary fat.
The majority of studies focusing on supplementary L-carnitine use look at its benefits for weight loss, including its effect on metabolic rate and fatty acid oxidation.
In the United States, cat foods labeled as "complete and balanced" must meet standards established by the Association of American Feed Control Officials AAFCO either by meeting a nutrient profile or by passing a feeding trial. Certain manufacturers label their products with terms such as premium, ultra premium, natural and holistic. Such terms currently have no legal definitions.
Dry cat food kibble is most often packed in multi-wall paper bags , sometimes with a plastic film layer; similar bag styles with film laminates or coextrusions are also used.
Wet cat food is often packed in aluminum cans or steel cans. Packaging regulations for cat food are often very similar to corresponding regulations for human foods. Vitamin deficiencies can lead to wide-ranging clinical abnormalities that reflect the diversity of their metabolic roles.
Twelve minerals are known to be essential nutrients for cats. Calcium and phosphorus are crucial to strong bones and teeth. Cats need other minerals, such as magnesium, potassium, and sodium, for nerve impulse transmission, muscle contraction, and cell signaling.
Many minerals only present in minute amounts in the body, including selenium, copper, and molybdenum, act as helpers in a wide variety of enzymatic reactions.
The table below lists the AAFCO nutritional profiles for cat foods along with the roles of vitamins and minerals in cat nutrition according to the National Research Council. Many nutrients can cause a variety of deficiency symptoms in cats, and the skin is a vital organ that is susceptible to dietary changes in minerals, protein, fatty acids, and vitamins A and B.
This results in dandruff, redness, hair loss, greasy skin, and reduced hair growth. Good overall nutrition is needed along with a well balanced diet. Zinc's connection to skin and coat health is due to its influence on regulating cellular metabolism.
One of the many functions of copper is to assist in production of connective tissue and the pigment melanin. Selenium works with vitamin E as antioxidants to handle the free radicals that are damaging to the body and the skin. Fatty acids are an important part of the cats diet, some are more important than others with respect to the cats diet and these are known as essential fatty acids. Alpha-Linolenic acid , Linoleic acid , and Arachidonic acid.
Vitamin A is a crucial nutritional component in the maintenance of feline skin and coat health. Vitamin E is an essential nutrient which needs to be included in the feline diet in order to protect the lipid components within cellular membranes of various tissues in the body. Biotin can be provided in feline diets through the addition of cooked eggs, liver, milk, legumes or nuts. Unlike humans, felines are able to utilize simple sugars glucose and galactose in a specialized pathway which occurs in the liver, referred to as the glucuronate pathway.
Therapeutic diets with low protein have been adopted by a number of big pet food manufacturers with the goal of supporting renal health for cats with chronic kidney disease CKD. Low protein diets can be formulated as a wet or dry food, with the main difference being the moisture content. Low protein diets should not be fed to cats with the liver condition known as hepatic encephalopathy because severe protein restriction can be detrimental to animals with this condition.
A high energy diet is generally high in fat. Compared to carbohydrates and protein , fat provides much more energy , at 8. A high energy diet is appropriate for cats who are undergoing growth, recovering from illness, are pregnant or lactating , as their energy requirements are higher than otherwise. To maintain a neutral energy balance and thus maintain body weight, energy intake should increase with energy expenditure.
It has been shown that cats offered four meals a day or a random number of meals a day have similar energy levels, greater than those fed only one meal per day.
As cats age, there is evidence that their metabolic energy requirements may increase,  especially after 12 or 13 years old,  but other evidence suggests that metabolic energy needs are not dissimilar at different ages. Pregnancy and lactation are strenuous periods on the female cat.
It has been found that nutritional support consistent with the resting energy requirement RER soon after surgery or the onset of illness decreases the mortality rate and the duration of hospitalization in cats.
Critical care diets are formulated to be highly palatable and digestible, as well as high energy density. Vegetarian or vegan cat food has been available for many years, and is targeted primarily at vegan and vegetarian pet owners. While a small percentage of owners choose such a diet based on its perceived health benefits, the majority do so due to ethical concerns. While there is anecdotal evidence that cats do well on vegetarian food,  studies on commercial and homemade vegetarian cat foods have found nutritional inadequacies.
As obligate carnivores, cats require nutrients including arginine, taurine, arachidonic acid, vitamin A, vitamin B12 and niacin found in meat sources. Plant sources do not contain enough of these. Vegetarian pet food companies try to correct these deficiencies by adding synthetically produced nutrients. Cats on a vegan diet can develop abnormally alkaline high pH urine as plant-based proteins are more alkaline than the meat-based foods which cats have evolved to eat.
Calcium oxalate stones can also occur if the urine is too acidic. Such stones can create irritation and infection of the urinary tract and require veterinary treatment. Organizations that advocate vegan or vegetarian diets for people have split opinions regarding vegetarian or vegan cat food. But the Vegetarian Society suggests people "consider carefully" and that many cats will not adjust to a vegetarian diet.
They provide a list of necessary nutrients that would need to be supplemented, and recommend that those who want to try should consult a veterinarian or animal nutritionist.
They do not recommend relying on supplements, because they may not contain necessary co-factors and enzymes and have not been studied for long term implications. Hence, regular at least, annual veterinary checkups of all companion animals is recommended, and brands may be occasionally varied. Even when adequately supplemented, vegetarian diets may present other risks, such as urine acidity problems.
While there are anecdotal reports linking a vegetarian diet with urinary tract problems, no documented case report or study exists.
In , the first study of the health of a population of long-term vegetarian cats was published in the Journal of the American Veterinary Medical Association. The study consisted of telephone questionnaires of the caregivers of 32 cats, and analysis of blood samples from some of the cats.
The blood samples were tested for taurine and cobalamin deficiencies. Cobalamin levels were normal in all cats. Taurine levels were low in 3 out of 17 cats tested, but not low enough to be considered clinically deficient. Formulation of a nutritionally adequate vegan cat diet has its limitations. The reason for these dietary essential nutrients can be found in the physiology section of the Cat page.
Protein and fat content in a vegan cat diet can be balanced by the inclusion of tofu and yeast. For instance, plant materials do not provide the preformed vitamin A which cats cannot synthesize, therefore supplementation is needed. Some ingredients of vegan cat diets that provide arginine, are pumpkin seed, almond, soya flour, lentil seeds and oat flakes see table one.
A minimum of 5 servings of fruit and vegetables a day is recommended for overall health. Experts encourage more vegetables than fruits for weight management so this leaves room for about 2 servings a day of fruit. In order to obtain the nutritional benefits from a varied diet, eat no more than one serving or one cup of pineapple a day.
Article last updated by Adam Felman on Thu 26 July All references are available in the References tab. Serum vitamin A and beta-carotene levels in children with asthma.
Journal of Asthma, 46 7 , Prospective study of intake of fruits, vegetables, vitamins, and carotenoids and risk of age-related maculopathy. Sodium and potassium intakes among US adults: American Journal of Clinical Nutrition, 96 3 , Inverse associations between serum concentrations of zeaxanthin and other carotenoids and colorectal neoplasm in Japanese.
International Journal of Clinical Oncology, 19 1 , Properties and therapeutic application of bromelain. Antioxidants and infertility treatment, the role of Satureja Khuzaestanica: Iranian Journal of Reproductive Medicine, 9 2 , Effect of carotene and lycopene on the risk of prostate cancer: PLoS One, 10 9 , e Plasma and dietary carotenoids, and the risk of prostate cancer: A nested case-control study [Abstract].
Cancer Epidemiology, Biomarkers, and Prevention, 13 2 , Sodium and potassium intake and mortality among US adults: MNT is the registered trade mark of Healthline Media.
Any medical information published on this website is not intended as a substitute for informed medical advice and you should not take any action before consulting with a healthcare professional. Privacy Terms Ad policy Careers. This page was printed from: Get the most out of Medical News Today.
Sign in Log in with your Medical News Today account to create or edit your custom homepage, catch-up on your opinions notifications and set your newsletter preferences. Register for a free account Sign up for a free Medical News Today account to customize your medical and health news experiences. Register take the tour. Table of contents Nutrition Benefits Diet Risks. How much pineapple should I eat per day?
In botany, the Cholodny—Went model , proposed in , is an early model describing tropism in emerging shoots of monocotyledons , including the tendencies for the stalk to grow towards light phototropism and the roots to grow downward gravitropism. In both cases the directional growth is considered to be due to asymmetrical distribution of auxin , a plant growth hormone.
From Wikipedia, the free encyclopedia. This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. September Learn how and when to remove this template message.
The stimulus of light on insects may also be seen as a type of ethological tropism.