Cattle vs. hippopotamus: Dung in rivers of the Savannah

June 16, 2020

In many regions of the world, populations of large mammalian herbivores have been displaced by cattle breeding, for example in Kenya the hippos by large herds of cattle. This can change aquatic ecosystems due to significant differences in the amount and type of dung input. Researchers from the University of Eldoret in Kenya, the University of Innsbruck and the Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB) have therefore taken a closer look at the dung of hippopotamus and cattle.

Animal dung can pollute water bodies with nutrients and impact water quality and the ecological functions of water bodies. For many aquatic ecosystems, however, the input of organic matter from the surrounding land is part of the natural matter cycling. In temperate latitudes, it is the leaf fall that brings nutrients into water bodies. In the rivers of the African savannah, it is the hippos with their dung. The increasing displacement of hippopotami by herds of cattle is changing the nutrient inputs into water bodies.

Professor Gabriel Singer, Dr. Frank O. Masese and their team investigated the effects of nutrient and carbon inputs from dung on aquatic ecosystems in experiments. The researchers also developed a mathematical model to compare dung inputs from cattle and hippos into the Mara River in Kenya. According to the mathematical simulation, despite lower manure introduction by the individual cattle compared to a hippopotamus, the large number of cattle gives this animal group overwhelming influence.

Cattle dung is more nutritious and stimulates the growth of plants, bacteria and algae

With cattle dung, higher amounts of nutrients such as nitrogen, phosphorus and dissolved organic carbon enter the Mara River. In the experiments, the researchers were able to show that, as a result, more plant biomass is formed with cattle dung. The biomass of bacteria and algae was also higher than with hippopotamus dung. This can change food webs in the river.

"Just the exchange of an animal species that lives on the edge of the river changes the ecological status of the river. Our results show the high species-specific importance of the various large herbivores; they also show how changes in land use or the composition of the species lead to unintended consequences that are not initially the focus of management measures, but which must always be taken into account. Especially with such crucial ecosystems as the waters of the savannah," Gabriel Singer explains the significance of the investigation.
-end-


Forschungsverbund Berlin

Related Cattle Articles from Brightsurf:

Genetic link between cattle temperament and autism
Researchers have discovered that cattle share an overlap of genes with humans that are critical in brain function and response to fear stimuli.

Mitigation of greenhouse gases in dairy cattle through genetic selection
Researchers in Spain propose mitigating methane production by dairy cattle through breeding.

Cattle vs. hippopotamus: Dung in rivers of the Savannah
In many regions of the world, populations of large mammalian herbivores have been displaced by cattle breeding, for example in Kenya the hippos by large herds of cattle.

Toxin promotes cattle-to-cattle transmission of deadly Escherichia coli strains
Shiga toxin subtype 2a (Stx2a) may play a key role in promoting the colonization and transmission of life-threatening Escherichia coli strains in cattle, according to a study published Oct.

Genomic analysis reveals ancient origins of domestic cattle
A new genome-wide analysis by Marta Pereira Verdugo and colleagues uncovers the complex origins of domestic cattle (Bos taurus), demonstrating why it has been difficult to untangle these origins from studies of modern breeds.

Identification of mechanisms of pesticide resistance in cattle ticks
Losses to herds due to parasites correspond to more than double the value of Brazil's annual beef exports, according to a study by Brazilian researchers published in Scientific Reports.

Genes that could lead to improvement of beef cattle are identified
Researchers identify 35 genes associated with reproduction, milk composition, growth, meat and carcass, health or body conformation traits in Gir cattle.

Human and cattle decoys trap malaria mosquitoes outdoors
Host decoy traps which mimic humans or cattle by combining odor, heat and a conspicuous visual stimulus could be effective at measuring and controlling outdoor-biting mosquitoes in malaria endemic regions, according to a study published in the open access journal Parasites & Vectors.

Leptospirosis strains identified in Uruguay cattle
Leptospirosis infections, caused by Leptospira bacteria, occur in people and animals around the world, but different strains of the bacteria may vary in their ability to cause disease and to jump between species.

Cattle may spread leptospirosis in Africa, study suggests
The bacterial infection leptospirosis is increasingly recognized as an important cause of fever in Africa.

Read More: Cattle News and Cattle Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.