It is given to horses suffering from chronic cough. It is used internally and externally as a dermal stimulant and antiseptic for treating eczema. Organum or Organy can refer to a number of different flowers, including the English Penny Royal and the wild and common Marjorams. I don't know which is referred to here. It is used as an astringent.
Murrain can refer to any one of a number of different diseases afflicting domestic animals.
Jalap is a powered drug prepared from the dried purgative root of the Mexican plant Exgonium purga , a member of the Morning Glory family. A drench is a large dose of a medicinal drink put down the throat of an animal. Laudanum refers to a preparation containing opium such as tincture of opium. Gentian root refers to the rhizome and roots of Gentiana lutea , a yellow-flowered gentian of southern Europe used as a tonic and stimulant for the stomach. Spike oil has long been used in combination with turpentine for curing old sprains and stiff joints.