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



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