Editing Kitten (section)

==Nutrition==
Felines are carnivores and have adapted to animal-based diets and low [[carbohydrate]] inclusion. Kittens are categorized in a growth life stage, and have high energy and protein requirements.<ref name=":0" /> When feeding a kitten, it is often recommended to use highly digestible ingredients and various components to aid in development in order to produce a healthy adult.<ref name="Sheridan">{{cite journal|last1=Sheridan|first1=Libby|title=Kitten nutrition|journal=Veterinary Nursing Journal|date=2012|volume=27|issue=6|pages=232–241|doi=10.1111/j.2045-0648.2012.00182.x|s2cid=219320741 }}</ref> In North America, diets certified by the Association of American Feed Control Officials (AAFCO) are accepted as adequate nutrition, thus kitten diets should be AAFCO approved to ensure full supplementation.<ref name="Ander" /> Key components of the diet are high fat content to meet caloric requirements of growth, high protein to meet requirements for muscle growth as well as supplementation of certain nutrients such as [[docosahexaenoic acid]] to benefit the development of the [[brain]] and optimization of [[cognition]].{{sfn|Greco|2014|p=265}}

=== Pre-weaning nutrition ===

==== Establishing immunity ====
Part of the kitten's immune system is the mucosal immune system, which is within the gastrointestinal tract. The mucosal immune system is largely responsible for coordinating proper immune responses by tolerating innocuous antigens and attacking foreign pathogens.<ref>Kabat, A. M., Pott, J., & Maloy, K. J. (2016). The mucosal immune system and its regulation by autophagy. ''Frontiers in immunology'', ''7''.</ref> In order to optimize kitten health and increase chances of survival, it is important to optimize the link between the [[gut-associated lymphoid tissue]] and the [[microbiota]] of the [[gastrointestinal tract]]. Lasting health and longevity can be accomplished partly through proper nutrition<ref name=":1" /> and establishing a healthy gut from birth through utilizing colostrum.<ref name=":2">Chastant‐Maillard, S., Aggouni, C., Albaret, A., Fournier, A., & Mila, H. (2017). Canine and feline colostrum. ''Reproduction in Domestic Animals'', ''52''(S2), 148-152.</ref>[[File:Laitche-P013.jpg|thumb|A litter of kittens suckling their mother]]Within the first two days after [[birth]], kittens acquire [[Passive immune system|passive immunity]]  from their mother's milk.<ref name="petnutritiontext">{{cite book|last1=Case|first1=Linda|last2=Leighann|first2=Daristotle|last3=Hayek|first3=Michael|last4=Foess Raasch|first4=Melody|title=Canine and Feline Nutrition: A Resource for Companion Animal Professionals|date=2011|publisher=Elsevier|page=210}}</ref> Milk within the first few days of parturition is called [[colostrum]], and contains high concentrations of [[immunoglobulin]]s.<ref name="petnutritiontext" /> These include [[immunoglobulin A]] and [[immunoglobulin G]] which cross the intestinal barrier of the [[Neonatal|neonate]].<ref name=":2" /> The immunoglobulins and [[growth factor]]s found in the colostrum begin to establish and strengthen the weak immune system of the offspring.<ref>Greco, D. S. (2014). Pediatric Nutrition. Veterinary Clinics of North America: Small Animal Practice, 44(2), 265-273.</ref> Kittens are able to chew solid food around 5–6 weeks after birth, and it is recommended that 30% of their diet should consist of solid food at this time.<ref>Little, S. (2013) Successful management of orphaned kittens. Journal of Feline Medicine and Surgery, 15, 201-210.</ref> The kitten remains on the mother's milk until around eight weeks of age when weaning is complete and a diet of solid food is the primary food source.<ref name=":0">Sheridan, L. (2014). Kitten Nutrition. Veterinary Nursing Journal, 27(6), 232-241.</ref>

=== Post-weaning nutrition ===

==== Fat ====
Until approximately one year of age, the kitten is undergoing a growth phase where energy requirements are up to 2.5 times higher than [[Maintenance of an organism|maintenance]].<ref>Hand, M. S. L., & Lon, D. (2000). Small animal clinical nutrition (No. SF 992. N88. L49 2000).</ref> Pet nutritionists often suggest that a [[Cat food|commercial cat food]] designed specifically for kittens should be offered beginning at four weeks of age.<ref name=":1">Case, L. P., Daristotle, L., Hayek, M. G., Raasch, M. F. (2011) Nutritional care of neonatal puppied and kittens. Canine and Feline Nutrition, 21, 209-219.</ref> [[Fat]] has a higher caloric value than [[carbohydrate]]s and [[protein]], supplying 9 kcal/g.<ref>The heats of combustion for glucose, sucrose, and starch are 15.57, 16.48 and 17.48 kJ/g respectively, or 3.72, 3.94 and 4.18 kcal/g.</ref> The growing kitten requires [[Arachidonic acid|arachidonic]] and [[linoleic acid]] which can be provided in [[omega-3 fatty acid]]s.<ref name=":0" /> Docosahexaenoic acid (DHA) is another vital nutrient that can be supplied through omega 3 fatty acid. Addition of DHA to the diet benefits the cognition, brain and visual development of kittens.<ref name=":1" />

==== Protein ====
Cats are natural [[carnivore]]s and require high amounts of protein in the diet. Kittens are undergoing growth and require high amounts of protein to provide essential amino acids that enable the growth of tissues and muscles.<ref name="petnutritiontext" /> It is recommended that kittens consume a diet containing approximately 30% protein, on a dry matter basis, for proper growth.<ref>{{Cite journal |author1-last=Rogers |author1-first=Quinton |author2-last=Morris |author2-first=James |date=April 1979 |title=Essentiality of Amino Acids for the Growing Kitten |journal=Journal of Nutrition |volume=109 |issue=4 |pages=718–723 |doi=10.1093/jn/109.4.718 |pmid=430271}}</ref>

[[Taurine]] is an essential amino acid found only in animal tissue; the mother cat cannot produce enough of it for her kittens.<ref name=":3">Sturman, J. A., Moretz, R. C., French, J. H., & Wisniewski, H. M. (1985). Postnatal taurine deficiency in the kitten results in a persistence of the cerebellar external granule cell layer: correction by taurine feeding. ''Journal of Neuroscience Research'', ''13''(4), 521-528.</ref> As it is an indispensable amino acid, it must be provided exogenously through the diet at 10&nbsp;mg per kg of bodyweight, each day.<ref>Burger, I. H., & Barnett, K. C. (1982). The taurine requirement of the adult cat. Journal of Small Animal Practice, 23(9), 533-537.</ref> Kittens deprived of taurine can experience poor growth<ref name=":3" /> and can result in retinal degeneration in cats.<ref>Markwell, P. J., & Earle, K. E. (1995). Taurine: an essential nutrient for the cat. A brief review of the biochemistry of its requirement and the clinical consequences of deficiency. ''Nutrition research'', ''15''(1), 53-58.</ref>

==== Carbohydrates ====
Felines are natural carnivores and do not intentionally consume large quantities of carbohydrates. The domestic cat's liver has adapted to the lack of carbohydrates in the diet by using amino acids to produce glucose to fuel the brain and other tissues.<ref>Schermerhorn, T. (2013). Normal glucose metabolism in carnivores overlaps with [[diabetes]] pathology in non-carnivores. ''Frontiers in endocrinology'', ''4''.</ref>   Studies have shown that carbohydrate digestion in young kittens is much less effective than that of a mature feline with a developed gastrointestinal tract.<ref>Harper, E. J., & Turner, C. L. (2000). Age-related changes in apparent digestibility in growing kittens. ''Reproduction, Nutrition, Development'', ''40''(3), 249-260</ref> Highly digestible carbohydrates can be found in commercial kitten food as a source of additional energy as well as a source of fiber to stimulate the immature gut tissue. Soluble fibre such as beet pulp is a common ingredient used as a fibrous stool hardener and has been proven to strengthen intestinal muscles and to thicken the gut mucosal layer to prevent diarrhea.<ref>Fukunaga, T., Sasaki, M., Araki, Y., Okamoto, T., Yasuoka, T., Tsujikawa, T., ... & Bamba, T. (2003). Effects of the soluble fibre pectin on intestinal cell proliferation, fecal short chain fatty acid production and microbial population. ''Digestion'', ''67''(1-2), 42-49.</ref>

===Diet composition===

====Amino acids====
The lack of readily available [[glucose]] from the limited carbohydrates in the diet has resulted to the adaptation of the liver to produce glucose from the breakdown components of protein—amino acids. The enzymes that breakdown amino acids are constantly active in cats. Thus, cats need a constant source of protein in their diet.<ref name="Sheridan" /> Kittens require an increased amount of protein to supply readily available amino acids for daily maintenance and for building new body components because they are constantly growing.<ref name="Sheridan" /> There are many required amino acids for kittens. [[Histidine]] is required at no greater than 30% in kitten diets, since consuming histidine-free diets causes weight loss.<ref name="Ander">{{cite journal|last1=Anderson|first1=P|last2=Baker|first2=D|last3=Sherry|first3=P|last4=Corbin|first4=J|title=Histidine, phenylalanine-tyrosine and tryptophan requirements for growth of the young kitten|journal=Journal of Animal Science|date=1980|volume=50|issue=3|pages=479–483|doi=10.2527/jas1980.503479x|pmid=7364684|s2cid=1583258}}</ref> [[Tryptophan]] is required at 0.15%, seeing as it maximizes performance at this level.<ref name="Ander"/> Kittens also need the following amino acids supplemented in their diet: [[arginine]] to avoid an excess of ammonia in the blood, otherwise known as [[hyperammonemia]], [[isoleucine]], [[leucine]], [[valine]], [[lysine]], [[methionine]] as a sulfur-containing amino acid, [[asparagine]] for maximal growth in the early post-weaning kitten, [[threonine]] and taurine to prevent central retinal degeneration.<ref name="Ander"/>

====Vitamins====

''Fat-soluble vitamins''

[[Vitamin A]] is required in kitten diets because cats cannot convert [[carotenes]] to [[retinol]] in the intestinal mucosa because they lack the necessary enzyme; this vitamin must be supplemented in the diet.<ref name="Sheridan" /><ref name="McDonald" /> [[Vitamin E]] is another required vitamin in kitten diets; deficiency leads to steatitis, causing the depot fat to become firm and yellow-orange in colour, which is painful and leads to death.<ref name="McDonald" /> Also, [[vitamin D]] is an essential vitamin because cats cannot convert it from precursors in the skin.<ref name="Sheridan" />

''Water-soluble vitamins''

Cats can synthesize [[Niacin (substance)|niacin]], but their breakdown exceeds the rate that it can be synthesized and thus, have a higher need for it, which can be fulfilled through an animal-based diet.<ref name="Sheridan" /> [[Pyridoxine]] (vitamin B<sub>6</sub>) is required in increased amounts because it is needed to produce amino acids.<ref name="Sheridan" /> [[vitamin B12|Vitamin B<sub>12</sub>]] is an AAFCO-recommended vitamin that is essential in the metabolism of carbohydrates and protein and maintains a healthy nervous system, healthy mucous membranes, healthy muscle and heart function, and, in general, promotes normal growth and development.<ref name="McDonald">{{cite journal|last1=MacDonald|first1=M|last2=Rogers|first2=Q|title=Nutrition of the domestic cat, a mammalian carnivore|journal=Annual Review of Nutrition|date=1984|volume=4|pages=521–562|doi=10.1146/annurev.nutr.4.1.521|pmid=6380542}}</ref> [[Choline]] is also a AAFCO recommended ingredient for kittens, which is important for [[neurotransmission]] in the brain and as a component of membrane [[phospholipids]].<ref name="Sheridan" /> Biotin is another AAFCO-recommended vitamin to support thyroid and adrenal glands and the reproductive and nervous systems.<ref name="Sheridan" /> Kittens also require [[riboflavin]] (vitamin B<sub>2</sub>) for heart health, [[pantothenic acid]] (vitamin B<sub>5</sub>), and [[folacin]].<ref name="McDonald" />

====Metabolism aids====
Since kitten diets are very high in [[calories]], ingredients must be implemented to ensure adequate digestion and utilization of these calories. Choline chloride is an ingredient that maintains fat [[metabolism]].<ref name="McDonald" /> [[Biotin]] and niacin are also active in the metabolism of fats, carbs and protein.<ref name="McDonald" /> Riboflavin is also necessary for the digestion of fats and carbohydrates.<ref name="McDonald" /> These are the main metabolism aids incorporated into kitten diets to ensure nutrient usage is maximized.

====Growth and development====
A combination of required nutrients is used to satisfy the overall growth and development of the kitten's body; there are many ingredients that kittens do not require, but are included in diet formulation to encourage healthy growth and development. These ingredients include: dried egg as a source of high quality protein and fatty acids, [[flaxseed]], which is rich in omega-3 fatty acid and aids in digestion, [[calcium carbonate]] as a source of calcium, and calcium pantothenate ([[vitamin B5]]) that acts as a [[coenzyme]] in the conversion of amino acids and is important for healthy skin.<ref name="McDonald" />

====Immunity boosters====
[[Antioxidants]] help support the development of a healthy immune system through inhibiting the [[oxidation]] of other molecules, which are essential for a growing kitten.<ref name="Sheridan" /> Antioxidants can be derived from ingredients such as carrots, sweet potatoes, spinach, vitamin E and vitamin E supplement, and [[zinc proteinate]].