Lactation Physiology (part 1) Isfahan University of Technology, Isfahan, Iran Lactation Physiology (part 1) By: A. Riasi (PhD in Animal Nutrition & Physiology)
Introduction and general information Cow milk is a nutritious liquid and known to be consumed by humankind for centuries. Its consumption had probably started with the domestication of the cow. The word milk is derived from Old English word meoluc, Dutch word melk, or the German milch. Milk contains protein, calcium, iodine, vitamins B2 and B12, phosphorus, and potassium. Nowadays, milk is processed before packaging to ensure that harmful bacteria in the milk are killed. Apart from being popular as a beverage, cows' milk is used to make a large number of products, including cheese, cream, butter, yogurt, liquid milk, ice cream, whey protein, and many more. Approximately 85% of the milk produced worldwide is sourced from cows and the other 15% from goats, sheep, buffalos, camels, horses, and donkeys. The recommended daily milk intake is three glasses a day. Until 2016, Russia and China were the world's biggest importers of milk. A closer look at the milk consumption of countries globally reveals that Finland tops the list. (www.worldatlas.com/articles/top-cows-milk-producing-countries-in-the-world, available at 2018). Milk is popular beverage worldwide, and is also used extensively in cooking and baking (adapted from www.worldatlas.com/articles/2018)
Introduction and general information Cow milk is a nutritious liquid and consumed by humankind for centuries. The word “milk” is derived from Old English word “meoluc”, Dutch word “melk”, or the German “milch”. The recommended daily milk intake is three glasses a day.
Introduction and general information
Countries Who Drink the Most Milk Introduction and general information Countries Who Drink the Most Milk Rank Country Per Capita Milk Consumption (Kg) 1 Finland 361.19 2 Sweden 355.86 3 Netherlands 320.15 4 Switzerland 315.78 5 Greece 314.69 6 Montenegro 305.87 7 Lithuania 303 8 Denmark 295.62 9 Albania 281.17 10 Romania 266.19 11 Luxembourg 265.9 12 Kazakhstan 262.61 13 Norway 261.52 14 France 260.48 15 Italy 256.1 adapted from www.worldatlas.com/articles/2018
Countries Producing the Most Milk Introduction and general information Countries Producing the Most Milk Rank Country Production (Metric Tonnes) 1 United States 91.3 2 India 60.6 3 China 35.7 4 Brazil 34.3 5 Germany 31.1 6 Russia 30.3 7 France 23.7 8 New Zealand 18.9 9 Turkey 16.7 10 United Kingdom 13.9 adapted from www.worldatlas.com/articles/2018
Introduction and general information Data from Dairy Co at http://www.dairyco.org.uk/library/market-information/datum/world-milk-production.aspx
Introduction and general information
Introduction and general information Adapted from: Wageningen Economic Research Report 2017
Introduction and general information
Introduction and general information Mammals are the vertebrates within the class Mammalia possession of a neocortex (a region of the brain), hair, three middle ear bone, and mammary glands. Females of all mammal species nurse their young with milk, secreted from the mammary glands.
Introduction and general information Mammals range in size from the 30–40 mm (bumblebee bat) to the 30-meter (blue whale).
Introduction and general information Mammary gland is a modified sweat gland. Mammary gland serves a reproductive function; nourishment of the neonate. Mammary glands are modified sweat glands, which secretes milk (exocrine gland) and serve as accessory glands to the reproductive system. Mammary gland development commences embryonically from ectoderm and mesoderm, The growth of mammary gland continue post natal even during lactation. The mammary gland can repeatedly undergo growth, functional differentiation, and regression. It relies on same endocrine (hormonal) support for development and function (gonadal steroids, prolactin, etc). In order to understand mammary gland physiology, anatomical features of the gland should be studied.
Introduction and general information Mammary gland can repeatedly undergo growth, functional differentiation, and regression. Relies on same endocrine support for development and function. Example: gonadal steroids, prolactin, etc.
Intermediate (abdominal) Introduction and general information Species Anterior (thoracic) Intermediate (abdominal) Posterior (inguinal) Total Goat, sheep, horse guinea pig 2 Cattle 4 Cat 8 Dog 2 or 4 8 or 10 Mouse 6 10 Rat 12 Pig 18 Proboscideans, primates Adapted from www.wikipedia.org, 2017
Introduction and general information The weight of empty cows udder is about 12-30 kg. The udder weight is affected by: Age Stage of lactation Amount of milk in the udder Inherited differences among cows Average capacity of cows udder is about 35 kg. The weight and capacity of the udder increases with age of the cow up to six years, with the greatest increases occurring between the first and the second lactation. It is very important for the dairy producer to have cows with udders that are large enough to produce large volume of milk and in the same time not to have them excessively large or with poor udder attachment.