Efficacy and Side Effects of Low Single Doses of Cloprostenol Sodium or Dinoprost Tromethamine to Induce Luteolysis in Donkeys.

This research paper focuses on evaluating the efficiency and side effects of four different doses of cloprostenol sodium and dinoprost tromethamine in inducing luteolysis in donkeys, as the literature on this subject is limited. The study concludes that a single low dose of these drugs can shorten the estrous cycle and result in fewer side effects.

Study Design and Objectives

• The study examined the impact of cloprostenol sodium and dinoprost tromethamine on donkeys. These two substances are analogs of the hormone Prostaglandin F2α.
• Its main objective was to investigate the efficiency and adverse effects of different doses of these drugs to induce luteolysis — the degradation of the corpus luteum (a temporary endocrine structure in female animals) — in female donkeys, known as jennies.
• The aim was to establish if a single low dose of these drugs could effectively induce luteolysis and shorten the estrous cycle — a physical cycle in mammals that results in ovulation and prepares females for pregnancy —with minimal side effects.

Methodology

• For the purposes of the experiment, seven Jennies were used. Each Jenny had nine cycles, amounting to sixty-three cycles in total.
• Seven days after ovulation, each Jenny was randomly given one of the treatments in a crossover design. The treatments included those using varying doses of cloprostenol sodium (CS) and dinoprost tromethamine (DT), and a control treatment with no administered drugs.
• After treatment, the jennies were observed for 30 minutes, and any adverse effects were recorded. The size of the corpus luteum and the duration of the estrous cycle were also noted.

Findings

• Results showed that all doses of cloprostenol sodium and dinoprost tromethamine were effective in reducing the estrous cycle length compared to the control cycle of the jennies.
• The volume of the corpus luteum decreased the day after treatment in all groups administered with the drugs.
• It was found that side effects were reduced as the doses of both Prostaglandin F2α analogs were lowered.
• The study concluded that a single low dose of dinoprost tromethamine (0.625 mg) or cloprostenol sodium (37.5 µg) can induce luteolysis and shorten the estrous length in jennies while producing fewer adverse effects.