Seed dispersal is the moving of seeds from one location to another. Seed dispersal is important for plants because it provides an opportunity for a scattered or dispersed growth of plants, high germination rate, less intra-competition, promotes genetic diversity and reduced extinction rate.
Most ecosystems are abundant with vegetation because animals tend to disperse and germinate their seeds.
Cattle are one of the few animals that contribute to the growth of the plants they forage on in a natural rangeland. Besides the dung that is highly utilizable for plant germination and growth, they also contribute to the existence of plants through dispersal of plant seeds. Cattle play a crucial role in the ecosystems structure and function, by dispersing seeds in all corners of the landscape, dispersing all sorts of plant seeds they forage.
Cattle disperse seeds in two common ways:
- Dispersal through dung
Cattle disperse tree seeds through dung deposits, this mostly occurs in trees with hard seed shells or that require seed dormancy treatments, they mostly have large woody protective outer coatings. The process of plant species that disperse through the gut is also referred to as endozoochory or endozoochorous dispersal (D’hondt & Hoffmann 2011). The pods and a proportion of the seeds are consumed by herbivores and form an important part of their diet (Gwynne, 1969). The seeds mostly pass undamaged through the cattle’s gut, the digestive juices then soften seed coat, and this facilitates water imbibition during germination (Tran & Cavanagh, 1984). This process also enhances favourable germination microclimates for the seeds, before they are deposited as dung. On the contrary, animals like goats fail to disperse tree seeds through dung deposits, this is because they tend to devour the entire pod.
- Dispersal with animal fur or coat
Majority of animals disperse seeds everyday unknowingly, this is achieved when the seeds cling on the fur or coat of the animal.
Grass and herbs have seeds that have adapted to opportunistically stick on the animal’s body, this provides the opportunity for seeds to move from one location to another. The mode of dispersing seeds through animal fur or coat is referred to epizoochory. Grass and herb seeds require mainly just rain drops to instantly sprout and prosper, with the assistance of dispersal by cattle, they tend to flourish.
An ecosystem is comprised of living organisms that play major and minor roles dispersing seeds to ensure a functional system.
Cattle is one of the animals that play a role to shape an ecosystem, by dispersing seeds, breaking seed dormancy and creating a fertile ground for plant growth.
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