Recovery and Germination of Malus sieversii (Ledeb.) M. Roem. (Rosaceae) Seeds after Ingestion by Cattle, Horses, and Sheep

Abstract

Livestock can transport seeds long distances by endozoochory due to their large home range and capacity to move among different habitats. However, differences in digestive system and body size between different livestock species may result in variations in the dispersal of domestic livestock. To test such effects, we explore the effects of endozoochorous seed dispersal of Malus sieversii by three livestock: cattle, horse, and sheep in the Ili Botany Garden, northwest of China. We collected seeds of M. sieversii and fed them to cattle, horses and sheep. After feeding, we collected all the seeds from their feces every 24 h for 6 days and determined the seed recovery percent, mean retention time, and germination percent of seeds after the effects of the digestive tracts of those three livestock species. Seed recovery percent in three livestock species feces were cattle (CS) (54.05%) > horse (HS) (4.83%) > sheep (SS) (0.45%). The mean retention time of seeds in the digestive tract of cattle, horses and sheep were 53 h, 57 h, and 45 h. The seed weight and seed coat thickness decreased significantly after the treatment of the digestive tract. After 80 days cold stratification of seeds, the germination percent of CK, CS, and HS were 61%, 69%, and 18%, respectively. The results indicated cattle is an effective seed disperser of M. sieversii, with a recovery and germination percent in endozoochorous seed dispersal by cattle than that of horse and sheep. Our findings may also provide a theoretical basis about regarding seed-centric grazing management decisions and keeping horse and sheep out of pastures during the fruit of M. sieversii shedding period.

Evaluation of the Potential Seed Dispersal Effectiveness of Malus sieversii (Lebed.) M. Roem. by Cattle

“…The seed dispersion pattern was estimated by integrating the movement trajectory distribution of cattle during seed retention in the digestive tract after the cattle had consumed fruits [51]. Xu et al (2022) observed that the seeds were no longer detectable in the cattle's feces on the sixth day following the ingestion of M. sieversii seeds [43]. To estimate the dispersal distance of seeds by cattle, we conducted GPS-tracking experiments during the fruiting period of M. sieversii in 2022.…”

“…Additionally, we discovered that the distribution area of M. sieversii is abundant with cattle feces containing its seeds and seedlings (Figure S1). Xu et al (2022) found that recovery rate of intact seeds of M. sieversii seeds after passing through the digestive tract of cattle was as high as 54.05%, and the recovered seed vitality was 100% [43]. However, comprehensive studies on the seed dispersal effectiveness of M. sieversii by cattle are still lacking.…”