Animal Science Terms - D
Dairy Cows: cows that are raised to produce milk
Dairy Goats: goats used primarily for milk production
Dairy Nutritionist: animal health professional who specializes in the nutritional needs of dairy cows. Nutritionists recommend optimal diets to farmers and monitor how cows respond to their feeding program
Dairy Plant: facility that receives, tests, and processes milk into dairy products
Dam: female parent
Degradable intake protein (DIP): see Rumen-degradable protein
Degradable protein: see Rumen-degradable protein
Dehulled: feed ingredients (grains, fruits, and nuts) that freed of their seed coats or outer shells through a mechanical process
Dehydrated: dried by removing moisture
Deoxyribonucleic acid (DNA): nucleic acid that is the genetic material determining the makeup of all living cells and many viruses. It consists of two long strands of nucleotides linked together in a structure resembling a ladder twisted into a spiral
Digestible energy (DE): apparent energy that is available to the animal by digestion, measured as the difference between gross energy content of a feed and the energy contained in the animal's feces (gross energy minus fecal energy)
Digestibility: measure of the apparent extent that a feed or nutrient is digested, usually expressed as a percentage of the amount consumed
Digestible NDF (NDFd): measure of how digestible the neutral detergent fibre fraction of forages is in ruminants. NDFd provides a better estimate of feed value than reliance only on measures of lignin and acid detergent fibre
Digestion: process of mechanical, chemical and enzymatic breakdown of consumed feeds into smaller components for absorption in the intestine of the animal
Digestive Tract: series of organs in the digestive system through which food passes, nutrients are absorbed, and waste is eliminated. In higher vertebrates, it consists of the esophagus, stomach, small and large intestines, rectum and anus
Direct-fed microbial (DFM): live microbial feed supplement that beneficially affects the host animal. Claims include reduced early mortality, increased growth rate, improved feed conversion, egg quality and animal health (e.g., prevent disease and/or aid recovery from illness). Lactic acid producing strains (e.g., Lactobacillus and Streptococcus) are common components of bacterial DFMs
Doe (Nanny): sexually-mature (over 1 year of age) female goat. Also, a female rabbit
Doeling: young female that is not yet sexually mature (less than a year old)
Dominance: gene is said to be dominant when its characteristic effect is expressed in the heterozygote as well as homozygote, i.e. Aa < AA. Ability of gene to cover in block out expression of its allele or genes that have observable effect when present in any one member of a chromosome pair
Donkey: domesticated animal of the equine family primarily used as a working animal
Draft Horse: large horse bred for hard, heavy tasks such as ploughing and farm labor
Drake: adult male duck
Drenching: administer an oral dose of liquid
Dressing Percentage: calculated by dividing the carcass weight by the live weight
Drove: group of swine
Drug: substance of synthetic, mineral, plant or animal origin used for pain relief or cure of disease and not as a nutrient
Dry Cows: cow that is not producing milk (lactating). The “dry” period lasts 50-70 days when a cow is preparing to give birth to a calf, which begins a new lactation period
Dry matter: everything contained in a feed sample except water (e.g., 100% dry matter). This includes protein, fiber, fat, minerals, etc. In practice, it is the total weight of feed minus the weight of water in the feed, expressed as a percentage
Dry period: period after lactation in which the animal does not produce milk
Dry-matter basis: used to compare nutrient composition or animal intake of feeds in a standardized fashion by eliminating differences in moisture content
Dry-matter intake: amount of (or prediction of the amount of) dry matter (moisture free feed) consumed by an animal. Typically, intake increases as the digestibility of the forage increases
Dry period: time when the female is not producing milk
Drylot: area with no vegetation generally an outside pen area
Duck: refers to a female of the duck family
Ducklings: baby ducks
Ducks: any wild or domesticated swimming birds of the family Anatidae, typically having a broad, flat bill, short legs, and webbed feet
Duodenum: beginning part of the small intestine, starting at the lower end of the stomach
Dystocia: difficulty in delivering the fetuses