Cover Image
close this book Animal traction
View the document About this manual
View the document About the author
View the document Acknowledgments
close this folder 1. Introduction
View the document What is animal traction?
View the document History of animal traction
View the document Why use animal traction?
View the document Some considerations
View the document How can animal traction be used?
View the document Before beginning: what do you need to know?
close this folder 2. Draft animal selection
View the document Popular draft animals
View the document Determining power requirements
View the document General rules concerning power requirements
View the document Method for determining size of the hitch
View the document Determining weights of animals
View the document Selection of individual draft animals
View the document Conformation
View the document Temperament
close this folder 3. Animal husbandry
View the document Sheller
View the document Nutrition
View the document Grooming
View the document Minor medical problems and first aid
close this folder 4. Training draft animals
View the document Before training begins
View the document General comments on training procedure
View the document Training cattle
View the document Program for training cattle
View the document Training horses, donkeys and mules
View the document Program for training horses, donkeys and mules
close this folder 5. Yokes and harnesses
View the document Yokes and harnesses for cattle
View the document Yokes and harnesses for horses, donkeys and mules
View the document How to harness a horse, donkey or mule
View the document Steering systems
View the document Breeching harness
close this folder 6. Hitches
View the document Safety rules
View the document Implement hitches
View the document Vehicle hitches
View the document 7. Field operations and implements
close this folder 8. Economic and technical assistance
View the document Farm planning assistance
View the document Equipment options
View the document Credit for equipment
View the document Credit for animals
View the document Procedures and controls
close this folder 9. Animal traction extension
View the document Extension education
View the document Appendix A: Animal power
close this folder Appendix B: Animal nutrition
View the document Energy needs: bovine animals
View the document Energy needs: equine animals
View the document Nutrient needs of draft animals: protein, minerals, vitamins
View the document Feeds and feed composition
View the document Calculating a ration
View the document Recommended rations and feeding practices
close this folder Appendix C: Disease recognition and control
View the document Parasites and parasitic disease
View the document Appendix D: Workshop and spare parts inventory
View the document Appendix E: Animal traction instruction forms
View the document Appendix F: Animal breeds used for power
View the document Bibliography
View the document Resources
View the document GIossary

General rules concerning power requirements

The above information, qualified by the following rules, makes it possible to determine the kind and number of draft animals needed to power various field operations:

• Given the soil conditions of a region, the weight of the implement to be used and the average depth at which the implement will work, the animal(s) must be able to deliver, for an extended period of time, a force equal to and preferably more than the total resistance, or draft requirement of the work. Tables 1 and 2 gives the draft requirements of various field implements.

• Work that requires frequent "peak efforts" (pulling a plow through rooted or rocky soil; pulling a cart over hilly terrain) tires animals quickly. The operator must compensate by reducing the length of the work day, reducing the intensity of the work (for example, taking smaller cuts with the plow), or providing frequent rests. The alternative is to increase the number of animals used.

• Individual animals do not pull to capacity when hitched in pairs or multiple arrangements. Tests have shown that the individual is 7.5 percent less efficient when it works within a pair. The percentage increases to 15, 22, 30 and 37 percent when the animal works in a team of three, four, five and six animals, respectively.

• As the line of pull is lowered (or as the angle between the line of pull and the ground becomes more acute), less power is needed to move the load. Donkeys and short-legged cattle can produce more power than their weight would indicate because they are closer to the ground.

• Animals deliver maximum performance only when the harness (yoke, collar or breastband) is properly fitted and provides a broad, smooth surface against which to push. Test evidence suggests that bovine animals can deliver 2550 percent more horsepower when harnessed in a breastband or collar rather than a yoke. The difference is explained in the lower point of draft, the increased comfort of the harness, and in the fact that the animal pushes against a much larger surface area.

• Animals must be in good health and properly trained.