03 - Livestock Ecology - 1 Abiotic environmental factors

Transcription

1 Eco-systems of agricultural landscapes and sustainable land use: Livestock systems 03 - Livestock Ecology - 1 Abiotic environmental factors

2 Classification of environmental elements, factors or influences by origin Abiotic factors: climate, ambient air, substrate, landscape, physical structures Biotic factors: life forms, populations, abundance and distribution, competition, predator-prey relations, symbiosis and mutualism, parasitism and diseases, the niche -concept Trophic factors: nutrients, food chains, food pyramids, fluctuating nutrient supplies, nutrient recycling, animal preferences, ecological efficiency

3 Abiotic Environmental Factors Substrate Atmosphere Landscape structures Physical structures Climate Air, water, soil Gases, particles Topography, physical structures Surfaces, restrictions Temperature, humidity, air movement, radiation, air pressure, precipitation

4 Schematic presentation of temperature variation in a dry equatorial lowland combining large diurnal and small seasonal variation Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

5 Schematic presentation of temperature variation in an arctic lowland combining minute diurnal and excessive seasonal variation Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

6 Mechanisms of heat exchange between body and environment Sweating Respiration Insensible perspiration Evaporation Radiation Convection Radiation Conduction

7 Main factors determining extent and position of the thermal comfort zone in warm blooded animals (example man) 50 Possible heat stroke Ambient tem mperature [ o C] Radiation (W/m²) Comfort zone Ventilation (m/sec) 1,0 0,4 0, Relative humidity [%]

8 Heat exchange mechanisms in warm blooded organisms Death Stress Comfort Stress Death A B C D E F Body core temperature Heat exch hange rate Heat production Non evaporative heat loss Body core te emperature Evaporative heat loss Ambient temperature

9 Typical reaction of an individual organism or a population to a gradient of a vital environmental factor Lower tolerance boundary Upper tolerance boundary Optimum zone vital func ction stress stress intolerance intolerance low Gradient of the environmental factor high

10 Breed differences in daily milk yields in response to different temperatures in a controlled environment at relative humidity between 40 and 60 % 25 Brown Swiss Jersey Holstein Brahman Temperature 0 C

11 Feed intake, daily gains and feed conversion of fattening pigs (60-100kg) at different ambient temperatures 1,2 12 daily gain [kg] 0,8 10 Daily gain [kg] 0,4 0-0,4 feed conversion [kg/kg] Feed intake [kg/d] Feed co onversion [kg/kg] -0,8 daily feed intake [kg] Ambient temperature [ o C]

12 Effect of varying ambient temperatures on egg weights per hen and day, egg size, daily laying performance and feed conversion o Ambient temperature [ o C] Egg weights Egg size Daily laying performance Feed conversion 0,040 0,035 0, [% %] [g] [kg/h]en/d [eggs/100 kg feed]

13 Reaction of animals and populations to climatic stress Time frame Process Mechanism Short-term Immediate reaction Behaviour Physiological Medium-term Acclimatisation Physiological Long-term Adaptation Genetic Very long-term Evolution Genetic

14 Short term behavioural response: seeking shade

15 Short term behavioural response: seeking shade

16 Short term behavioural response: seeking shade

17 Short term behavioural response: wallowing

18 Short term behavioural response: huddling

19 Diurnal changes in core body temperature in dromedaries and Greater Desert Jerboa in on a summer day in the southern Sahel 44 Core body temperature [ º C] Greater Desert Jerboa Dromedary Time of day After Schmidt-Nielsen, 1954

20 Long term behavioural response: building shade

21 Physiological medium term response: seasonal fur change

22 Physiological medium term response: seasonal fur change

23 Physiological medium term response: seasonal fur change

24 Long term genetic response: adaptation Estimated evaporation [%of body weight per hour] Kangaroo Rats (0,1 kg) Rabbits (2,5 kg) Dogs (16 kg) Humans (70 kg) Donkeys (145 kg) Estimated water loss [% of body weight per hour] for mammals in summer in the dry tropics Body weight [kg] Dromedaries (500 kg)

25 Bio-climatic specialisation of various cattle breeds Large Zebu Breeds Scorching Dwarf breeds Humid Ambient te emperature 0 [C] Keen Smooth coated large taurine breeds Relative humidity [%] Raw Long coated taurine breeds

26 Brahman Zebu

27 Ndama Cattle

28 Highland Cattle

29 Charolais

30 Sheep breeds typical for some bio-climatic regions Sahel Djallonke East Friesian Dairy Scottish Blackface

31 Goat breeds typical for some bio-climatic regions Jamnapari West African Dwarf Boer Norwegian Dairy