My pioneer family's homely refrain was a reflection of the met nutritional needs of the working class , and the assurance that things were in working order at a time of deprivation. A hearty meal for both horse and man, eaten quickly, provided jet fuel for hard work. Possibly the more publicly flatulent , either horse or man were what the jingle writer considered both unrestrained and therefore more " gung ho" in capability. Such an advantage in a hired man should be considered.
The volume of intestinal gas is increased with a high carbohydrate diet as would be expected in pioneer days. Moreover the "poor man's food " of Brassicaceae and beans would have further contributed to this gas. There is, when investigated, a high correlation of intestinal gas and caloric intake. Mean total volume of intestinal gas produced in a day in a healthy adult averages 705 ml. and this includes both bolus gas (swallowed air), and gas from colonic fermentation. Bolus gas would be increased considerably in the trencherman. The speed with which the trencherman " fueled up " on these foods increased the air swallowing, somewhat therefore reduced the percentage of colonic fermentation gas, and made the emissions more fragrant.
The daily and nightly rate of emission of flatus was variable but enhanced by heavy ploughing and digging, as the horse and man toiled in the soil in those pioneer days, Photos of of pioneer days often reveal a sturdy obesity in the hired man that bespeaks strength and serves as a base of reserve when horse and man enter stages 6 and 7 which leave one atrophied. * Obesity sort of getting a head start in life's race. Low carbohydrate diets associated with high fibre meals reduce flatulence considerably but at the expense of energy; not desirable in the case of a hired man.
There was little or no mechanization in the farm on those days, One couldn't work to advantage on the farm without the hired man and the horse, both running on all cylinders. It's just no surprise the horse and man lived in their own quarters, apart from the rest.
* As You Like It Act 2 Scene 7