User:Ehuong/sandbox

Diet
Balanced nutrition has proved to be a vital requirement in order to ensure longevity and optimal welfare in the canine companion. Nutrition becomes increasingly important to the gestating and lactating bitch in order to support both herself and her puppies. Balanced nutrition can be obtained by feeding the bitch commercial formulated puppy or performance diets due to similar nutrient profiles. Diets for gestating and lactating bitches should support lactation, bitch and puppy immunity, coat and skin health, puppy nervous system and vision development, and gastrointestinal health, as indicated by the National Research Council. Gastrointestinal health applies to all dogs, and strategies in normal dog food can be used for gestating and lactating bitches as well.

Lactation
Lactation is the process of secreting milk from the mammary glands. There seems to be little differences in milk composition between dog breeds. Colostrum is the milk first provided to puppies and is the only indication where milk changes during the lactation period. Canine milk contains 21.2% dry matter, 8.23% crude protein, 8.11% fat, and 4.86% sugar, and has an energy density of 1.41 kcal/gram on average. There is no evidence that milk composition changes with a larger litter, which can suggest that bitches will provide quality milk or none at all if nutrient deficient.

A main component of milk is calcium and phosphorus, and the lactating bitch will often utilize her own bone reserves to meet milk requirements if she lacks supplementation. However, calcium supplementation must be controlled as too little or too much may lead to eclampsia. To maintain the bitch’s bone mineral content and promote skeletal development and growth for the puppy, the Association of American Feed Control Officials (AAFCO) has set a minimal requirement of 1% calcium and 0.8% phosphorus, as well as a Ca:P ratio ranging from 1.2:1 to 1.4:1. This ratio accounts for antagonisms between minerals and vitamins. Water also plays an important role in milk production, indicated by the increase in the bitch’s water requirement during lactation. Water can be offered ad libitum, and it has been seen that with free access to water bitches have increased their intake by 8%.

Immunity
Nutrition plays a role in the immunology of the mother; it is able to sustain and develop the immune response within the female dog, as well as develop and sustain her litters’ immunity. The immune system contains antibodies, which are vital for fighting pathogens and maintaining disease resistance; these antibodies are composed of large protein molecules. It is recommended to feed them an energy-dense diet, approximately 30% protein and 20% fat, which would not only meet her energy requirements, but meet the protein requirements of the immune system in developing these antibodies. Colostrum aids in the transfer of immune protection from mother to offspring. The antibodies provided by colostrum can only be absorbed by the puppies during their first 24 hours of life. Protein levels in the diet also impact the immunity of the puppies, as a protein deficiency can cause problems with immunity, and even carbohydrate intolerance. Vitamins, more specifically vitamins C and E, in the diet are involved in the mother's immunity, as the high stress associated with gestation, whelping and lactation can cause oxidative stress and immune suppression. Vitamins E and C are immunostimulatory, and can aid in enhancing the immune response. An optimal omega-6:omega-3 fatty acid ratio between 5:1 and 10:1 should be incorporated in the diet, as the mothers’ essential fatty acid status can be decreased by the stress that pregnancy and lactation has on her body. Essential fatty acids are needed to supply her puppies with fetal tissues with fatty acids through her milk. The omega-3 fatty acid docosahexaenoic acid (DHA) promotes a healthy immune system in utero and in healthy puppies, and it is most commonly included in the diets in the form of fish oils. Omega-3 also has a role in decreasing inflammation, anti-tumor effects, blood lipid concentrations, as well as the management of diseases that are inflammatory in nature.

The immune system functioning in the intestine is involved in the health of the mother as well, as it is the largest immune organ in the body. Bacteria is involved in the intestinal immune system of a dog, as it influences the function of the intestinal mucosa; the levels of bacterial population in the gut regulates the immune system within the intestine.

Probiotics, a live microbial food supplement, can improve this bacterial balance in the intestine, and stimulate the production of immunoglobulin IgA, which is an antibody that protects mucosal surfaces against harmful bacteria. The most common type of probiotics used in the diet are bifidobacterium and lactobacillus. Prebiotics are non-digestible food ingredients which can stimulate the growth or activity of beneficial bacteria in the colon, which can improve host health; common prebiotics used in the diet are fructo-oligosaccharides (FOS) and mannanoligosaccharides (MOS). Prebiotics can bind to the receptors on pathogenic bacteria, preventing them from attaching to glycoproteins on the intestinal wall, rendering these bacteria unable to cause disease in the gut. Gut-associated lymphoid tissues (GALT) in the intestine recognize pathogens and initiate a response, these responses can be impacted by the bacterial populations within the intestine. Including fibre in the diet can benefit the mother’s immune system as well, such as feeding high fermentable fibre (e.g. beet pulp, plant fibres), which increases the amount of T-cells in GALT.

Skin and coat health
The mineral requirements of mammals has often been overlooked due to the small proportions that are needed in the diet, when compared to macromolecules (such as carbohydrates, proteins and lipids). However their inclusion in the diet has proven to be of utmost importance to overall health and physiological function. Zinc (Zn), Copper (Cu), and Manganese (Mn) have been shown to be important to reproductive performance, as well as skin and coat health during gestation and lactation. Deficiencies of any of these can lead to a reduction in litter size, or even an inability to maintain pregnancy (in extreme cases). While these three micronutrients have various roles in the body and overall health, Zinc is required for reproductive maintenance, as well as the repair and maintenance of epithelial cells. Copper provides strength to collagen, which is needed abundantly for the entire body as well as female reproductive system. Finally, Manganese is an important micronutrient for sex hormone production and blood clotting factors which are particularly important during whelping. While the dietary requirements for minerals can be difficult to estimate (due to the mineral antagonists that exist), the National Research Council of Canada (NRC) has created a guideline for each of these mineral recommendations in the diet. Some dog food diets will provide minerals in the form of a chelate; chelated minerals are minerals that are chemically bound to an organic molecule (such as an amino acid), and therefore have a greater potential for absorption than inorganic minerals do. It has been reported that bitches consuming diets with chelated Zn, Cu, and Mn have better coat health, as well as more puppies, than bitches fed a diet with inorganic minerals. However, there seems to be no difference in puppy growth rate, whether the bitch is fed an inorganic form or a chelated form in the diet.

Puppy nervous system and vision development
Nutrition for the gestating/lactating bitch includes both the needs and requirements of her and those of her puppies. The inclusion of both omega 6 and omega 3 fatty acids in the diet have been shown to improve both pregnancy in the bitch and development of the puppies in utero and after birth. An optimal balance of omega 6 to omega 3 fatty acids between 5:1 and 10:1 is associated with bigger litters and fewer stillbirths in the bitch as well as improved hair, coat, and immune function in the puppies. Omega 3 fatty acids such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are essential for proper neurological development of the puppies. These omega 3 fatty acids, specifically DHA, are required for normal development of both visual and auditory systems in the puppies. Studies show that when fed a diet inclusive of DHA puppies had improved visual, motor, and cognitive function. An optimal balance of omega 6 to omega 3 fatty acids can be provided through fish meal or fish oils. An important vitamin in human pregnancy is folic acid which is associated with the occurrence of midline defects which relate to the closure of the neural tube, including spinal bifida and cleft palates. When Boston terriers were supplemented with folate, it was shown that the number of puppies with cleft palates decreased. These are all nutritional supplements to consider when choosing a diet to best optimize the health and development of both the bitch and her puppies.

Gastrointestinal Health
Dietary fibres are added to canine diets to help with the digestibility and fermentability of other dietary ingredients. Fibre is required to obtain and maintain healthy gastrointestinal motility and gut flora. Common diets used for gestating and lactating dogs typically contain higher proportions of moderate and highly fermentable fibres such as beet pulp, barley, and fructooligosaccharides. This differs from maintenance diets, which commonly use sources of indigestible fibre such as cellulose and wheat bran. Beet pulp has an effective complement of viscous and non-viscous structural carbohydrates. Viscous polysaccharides are those that are extensively fermented by the gut microbial population, and are partly responsible for the beneficial effects on glucose and fatty acid metabolism, and bile acid synthesis. Beet pulp is also high in hemicellulose, which is a non-viscous polysaccharide that has similar effects as a viscous polysaccharide. When beet pulp is added, it has been shown that the frequency of defecation increases, and the retention time, or time of digestion, decreases. Barley is also used as a dietary fibre in dog foods and is rich in fermentable and soluble fibres. Barley contains high levels of β-glucans, which are water-soluble fibres that are able to form highly viscous solutions that increase transit time and nutrient absorption. Fructooligosaccharides are a substrate, or place of attachment for many good bacteria such as bifidobacterium and lactobacillus. This fibre can play a role as both a prebiotic and probiotic. Prebiotics are foodstuffs that either suppress or enhance replication of specific colonic bacteria in the host, whereas probiotics are bacteria or yeast that are fed to alter colonic bacterial populations. These both play a role in optimizing gut immunity and affects microbiomes in all parts of the body. In short, to attain optimum health, a fibre source should be moderately fermentable for the production of short-chain fatty acids with a non-fermentable component to provide bulk.