Principles of adaptation in domesticated ruminants to life in harsh environments Nissim Silanikove, Ephraim Maltz Department of Physiology and Nutrition, Institute of Animal Science Agricultural Research Organization, The Volcani Center, P.O. Box 6, Bet Dagan 50 250, Israel.
In order to be sure what’s our goals are, we should know how we came to this point and where we stands now
INTRODUCTION • Brief history of livestock industry (domestication) and current trends )the post-world war IIagricultural revolution) • Brief history of main relevant concepts developed and the heroes (the Scientist) involved.
Boran cattle were domesticated in 3 parts of the world:Bos Indicus (Zebu cattle) domesticated in the Indus Valley (Pakistan) 4000BCEuropean Bos Taurus domesticated in eastern Europe 6000 BCAfrican Bos Taurus domesticated in the eastern Sub-Saharan area 8000 BCThe Boran developed in eastern Africa and the main Boran hotspot was the Borana plateau in southern Ethiopia. That was a point where all the different breeds migrated through to their various destinations in Africa. European Bos Taurus- 24% Bos Indicus- 64% African Bos Taurus- 12%
The Celtic cattle from which Dexters developed (Book of Kells, dating from around AD 800)
Maintaining crossbred populations of dairy cattle in the tropicsI.L. MASON
Goats seem to have been first domesticated roughly 10,000 years ago in Asia Minor, Persia and Pakistan • Ancient cultures and tribes began to keep them for easy access to milk, hair, meat, and skins. This methods are utilized today
The domestic goat (Capra aegagrus hircus) is a domesticated subspecies of the wild goat of southwest Asia . Markhor (Wilde goat from Pakistan)
The Angora goat originated in the district of Angora in Asia Minor. Record of the Angora dated between 1571 and 1451 B.C
Domestic sheep Domestic sheep are descended from the mouflon (Ovis orientalis) that is found from the mountains of Turkey to southern Iran. Evidence for domestication dates to 9000 BCE in Iraq
The scale below provides an indication of how recent the phenomenon of farming is: • The world was formed ca 4, 600 million years ago. • Eukaryotic life forms: ca. 1,000 million years ago • First hominid life forms 4 million years ago (hunter gatherers) • First human farmers: about 12,000 years ago. • Global Agricultural Evolution: 1650 – 1850 AD • Modern Agricultural Evolution: 1950 - present
Milk energy and heat increment of lactating cows in the US from 1940 to 1995 calculated from USDA annual milk production data.Conversion of ME into milk energy at an average efficiency of 65% was assumed )LPS, ( 2002.
Milk energy and heat increment of lactating Holstein cows in Israel from 1934 to 1997 calculated from average annual milk production data (Israel Cattle Breeders Association, 1997). Conversion of ME into milk energy at an average efficiency of 65% was assumed. (LPS, 2002)
Bodyweight of Holstein heifers at 24 months of age between 1934 and 1987 in the US (LPS, 2002)
CONCLUSIONS • The agricultural revolution during the last 4 decades has change ruminants livestock such as modern dairy cows, modern Beef cows and modern dairy goats more than 1000 years of traditional agriculture. • This is most likely the reason why Maltose hypothesis was not fulfilled; but it also raised many question regarding the proper route for the future development of the industry.
LAVOISIER ANTOINE LAURENT(August 26 1743 - May 8 1794) Some of Lavoisier's most important experiments examined the nature of combustion, or burning. Burning is a process that involves the combination of a substance with oxygen. Lavoisier conducted experiments that showed that respiration was essentially a slow combustion of organic material using inhaled oxygen.
DR. CLAUDE BERNARD(1813-1878) Milieu intérieur, internal environment, was the original concept of Bernard that to this day is of utmost importance. Conditions in the world around us constantly change, but delicate balance of internal characteristics of our bodies is not affected. It is achieved through what we call it today homeostasis or steady state.
Knut Schmidt-Nielsen is one of the most influential comparative physiologists of our time: Principles of adaptation, body size
Scholander, Per Fredrik (Thorkelsson) (Norway- United States 1905-1980)physiological ecology Scholander, P. F., V. Waters, R. Hock, and L. Irving. 1950. Body insulation of some arctic and tropical mammals and birds. Biol. Bull, 99:225-235. The Development of the Thermo-Neutral Zone Concept
Some second generation of prominent environmental and comparative physiologist that studied domesticated ruminants • Charles Richard Taylor (USA), a leading experimental vertebrate physiologist (1939-1995): Thermoregulation, locomotor energetics and biomechanics, muscular energy and endurance capacity. • Amiram Shkolnik (ISRAEL)(1923-2004): Desert physiology: coping with shortage of water and food, lactation physiology in the desert, thermoregulation. • Walter Victor Macfarlane (AUSTRALIA)(1913-82): Comparative aspect of water and energy metabolism among genera and species of mammals.
Principles of adaptations to harsh environment • The strain: heat and radiation • The adaptation: physiological and behavioral thermoregulation • The strain: Shortage in water • The adaptation:Low requirement, a capacity to endure severe dehydration and rapid rehydration • The strain: Shortage of energy protein and essential nutrients • The adaptation:Small body size, low and variable metabolic requirements, superior digestive capacity, efficient use of key metabolites (recycling), skilful grazing behavior.
Schematic presentation of the zones of survival, well being, and homeothermy in respect to environmental conditions in ruminants: Stage I: the innocuous stage, Stage II: the aversive stage, Stage III: the noxious stage, Stage IV: the extreme stage
Average effect of temperature and day length on milk and protein yield
PANTING (BREATH) RATE IN SHEEP AND GOATS 50-80 BREATH/MIN – STAGE II 80-140 BREATH/MIN – STAGE III >140 BREATH/MIN – STAGE IV
COPING WITH SHOTAGE OF WATER • FEATURES • ADAPTAIONS • PHYSIOLOGICAL STAGES
Nature234, 483 - 484 (24 December 1971) • Hierarchy of Water and Energy turnover of Desert Mammals • W. V. MACFARLANE, B. HOWARD, H. HAINES*, P. J. KENNEDY & C. M. SHARPE • Bufalo:200 ml./kg/24 h • Bos taurus: 150 ml./kg/24 h • Bos Indicus: 123 ml./kg/24 h • Cattle > Sheep> goats > camels