Publications by authors named "Charles K Gachuiri"

Fire and herbivory have profound effects on vegetation in savanna ecosystems, but little is known about how different herbivore groups influence vegetation dynamics after fire. We assessed the separate and combined effects of herbivory by cattle and wild meso- and megaherbivores on postfire herbaceous vegetation cover, species richness, and species turnover in a savanna ecosystem in central Kenya. We measured these vegetation attributes for five sampling periods (from 2013 to 2017) in prescribed burns and unburned areas located within a series of replicated long-term herbivore exclosures that allow six different combinations of cattle and wild meso- and megaherbivores (elephants and giraffes).

View Article and Find Full Text PDF

Gastrointestinal parasite infections are among the major limitations to production in sheep in many parts of the world. It is important to continually assess their levels of infection in order to institute control measures and reduce the impact. This study determined the factors associated with the strongylida egg counts in sheep on selected farms in peri-urban Nairobi, Kenya.

View Article and Find Full Text PDF

Pretreating fibrous feedstuffs with exogenous enzymes may improve their utilization in broiler chickens. Pretreatment of wheat middlings () and sunflower meal () with fiber degrading enzymes () was investigated for 1) in vitro solubilization of crude protein () and fiber-degrading (experiment 1), and 2) apparent retention () of CP, neutral detergent fiber (), nitrogen corrected apparent metabolizable energy (), as well as the concentration of ceca digesta metabolites in broiler chickens (experiment 2). In experiment 1, WM was pretreated with FDE and SM with FDE ± protease and incubated in a shaker for 24 or 48 h at 40°C and 200 rpm.

View Article and Find Full Text PDF

Growth performance, gizzard weight, ceca digesta short-chain fatty acids (SCFA), and apparent retention (AR) of components were investigated in broilers and turkeys in response to cereal grain type, fiber level, and multienzyme supplement (MES) fed from hatch to 28 d of life. 480-day-old male broiler chicks and equal number of turkeys were placed separately in metabolism cages (10 birds/cage) and allocated to 8 diets. The species-specific diets were a corn or wheat-based basal diet without (LF) or with 10% corn DDGS or wheat middlings (HF) and fed without or with MES.

View Article and Find Full Text PDF

The objective of this study was to investigate the effect of varying roughage and concentrate proportions, in diet of crossbreed dairy cattle, on the composition and associated functional genes of rumen and fecal microbiota. We also explored fecal samples as a proxy for rumen liquor samples. Six crossbred dairy cattle were reared on three diets with an increasing concentrate and reducing roughage amount in three consecutive 10-day periods.

View Article and Find Full Text PDF
Article Synopsis
  • - Methane is a potent greenhouse gas produced by ruminants like cows during digestion, resulting in emissions from belching and flatulence; this study analyzed rumen and dung samples from 48 dairy cows in Kenya and Tanzania to explore methanogen diversity and methane metabolism enzymes.
  • - The analysis revealed a rich diversity of methanogens, identifying 87 species across various taxonomic categories, with Methanomicrobia and Methanocorpusculum labreanum being the most abundant.
  • - The study highlights the importance of functional enzymes related to methane metabolism, noting that these findings could help develop strategies for reducing methane emissions while ensuring the health of the host animals; it also suggests further research to classify unclassified species.
View Article and Find Full Text PDF

To enhance milk quantity and quality which have continued to decrease in Kenya, various stakeholders have intervened through promotion of technical dairy innovations at the farm level including improved cow feeding, health management, promotion of exotic breeds, and milking hygiene. At the milkshed level, stakeholders' focus has been on organizational innovations, specifically milk sale by farmers through groups. This study sought to characterize dairy innovations that have been adopted by farmers in the milkshed of three milk processors including New Kenya Co-operative Creameries Sotik (NKCC Sotik), Happy Cow Limited (HCL), and Mukurweini Wakulima Dairy Limited (MWDL), representing one state, private, and farmer-owned processor, respectively.

View Article and Find Full Text PDF

Analysis of shotgun metagenomic data generated from next generation sequencing platforms can be done through a variety of bioinformatic pipelines. These pipelines employ different sets of sophisticated bioinformatics algorithms which may affect the results of this analysis. In this study, we compared two commonly used pipelines for shotgun metagenomic analysis: MG-RAST and Kraken 2, in terms of taxonomic classification, diversity analysis, and usability using their primarily default parameters.

View Article and Find Full Text PDF

Background: Helminth infections in small ruminants are serious problems in the developing world, particularly where nutrition and sanitation are poor. This study investigated the burden and risk factors of gastrointestinal nematode parasite infections in sheep and goats kept in smallholder mixed farms in the Kenyan Central Highlands. Three hundred and seven small ruminants were sampled from 66 smallholder mixed farms in agro-ecological zones 1 (humid) and 3 (semi-humid) in the Kenyan Central highlands.

View Article and Find Full Text PDF