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Effects of camel feed supplementation on milk yields and composition during early pregnancy period
(AJSTSS, 2022-09-26) Thiakunu, F.K1; Njehia, K.B2; Nguhiu, P.N2 and Arimi, Joshua M1
A study was conducted between January and March 2022 which was the camel mating season at Ngaremara
ward of Isiolo County. The objective was to determine the effect of feed supplementation on milk yield and
composition in early pregnancy. It is documented that camels in pastoral environment drop milk production
immediately after conception. There is limited information in literature on effects of supplementation on milk
production at this stage. A complete randomized design was used to select ten camels which were
supplemented with a formulated concentrate supplement made of locally available materials and ten unsupplemented which was the control. All camels were dewormed at the beginning of the study. Formulated
feeds were gradually introduced to ten camels by adding 1 kg daily and enticing them with green acacia pods
for 2 weeks until all supplemented were able to feed 3.5 kgs in the evening after grazing. Mating took place
naturally using a bull between 6th January and 15th February 2022 and one supplemented and two unsupplemented camels were not mated. Milking was done in the mornings after allowing the calves to
stimulate the teats for the milk letdown reflex. Production of milk in litres was recorded daily and total
production per camel tabulated on weekly basis. Milk samples were taken every week and analyzed for
protein and fat levels. Statistical data analysis for milk yields was done by comparing weekly means using
ANOVA with the help of SPSS. Mean weekly milk yields per camel in litres for the supplemented and unsupplemented was 8.6067 ± 0.23691 and 8.0797±0.26185 respectively. There was a consistent increase in
milk production for the supplemented camels with a significant increase of 1.63 litres at week 3 (P<0.05). The
un-supplemented camels had a consistent drop of milk production which was more significant (P<0.05) at
week 5 and 7. Supplemented camels milk had percentage increase in fat content of 3.470 ±0.0300 compared
to 3.157±0.0228 for the un-supplemented. The supplemented camels were mated earlier than the unsupplemented. Six supplemented and five un-supplemented were confirmed pregnant through the indigenous
knowledge method of cocking the tail (kutoa mkia) when the male or a person approaches. The study
concludes that feed supplementation can positively affect the lactation curve and fertility in camels. It is
recommended that camels be supplemented with feed formulations made from locally available materials at
around the time of mating to improve production and reproduction. Further studies are recommended to
determine the effect of pregnancy on milk yields and composition.
Draft genome sequence of two Aspergillus aculeatus isolated from cashew nuts from coastal Kenya
(American Society for microbiology, 2024-09-16) Manase Onyango Aloo,1,2 Pauline Wambui Gachanja,1,2 Eugene Mwanza Muzami,1,2 Kyalo Katua,1,2 Dennis Wamalabe Mukhebi,1,2 Colletah Rhoda Musangi,1,2 Bicko Steve Juma,2,3 Wilton Mwema Mbinda1,2
Aspergillus aculeatus is a common saprophyte and ubiquitous fungus
belonging to section Nigri. They produce diverse secondary metabolites which are
important in biological processes and industrial applications. We present the draft
genome sequences of two A. aculeatus isolated from cashew nuts from coastal Kenya.
Aspergillus population diversity and its role in aflatoxin contamination of cashew nuts from coastal Kenya
(PLOS one, 2025-01-24) Colletah Rhoda Musangi1,2, Bicko Steve Juma2 , Dennis Wamalabe Mukhebi1,2, Everlyne Moraa Isoe1 , Cromwell Mwiti Kibiti3 , Wilton Mwema MbindaID1,2*
Cashew nuts are among the main cash crops in coastal Kenya, due in large part to their high
nutritional value. Unfortunately, they also make them highly susceptible to mold contamination, resulting in biodeterioration of the nutritional value and potential contamination with
toxic secondary metabolites, such as aflatoxins, that cause them to be rejected for sale at
the market. We determined the population diversity of the Aspergillus species and their role
in aflatoxin contamination in cashew nuts in selected coastal regions of Kenya. Fifty raw
cashew nut samples were collected from post-harvest storage facilities across three counties in Kenya’s coastal region and examined for moisture content and the presence of
Aspergillus fungi. About 63 presumptive isolates were recovered from the cashew nuts. ITS
and 28S rDNA regions were sequenced. The aflD, aflM and aflR genes were amplified to
identify the potentially aflatoxigenic from the Aspergillus isolates. The Aflatoxins’ presence
on the isolates was screened using UV and the ammonia vapour test on coconut milk agar
and validated using ELISA assay. A comparison of cashew moisture content between the
three counties sampled revealed a significant difference. Sixty-three isolates were recovered and identified to section based on morphological characters and their respective ITS
regions were used to obtain species identifications. Three sections from the genus were represented, Flavi and Nigri, and Terrei with isolates from the section Nigri having slightly
greater abundance (n = 35). The aflD, aflM and aflR genes were amplified for all isolates to
assess the presence of the aflatoxin biosynthesis pathway, indicating the potential for aflatoxin production. Less than half of the Aspergillus isolates (39.68%) contained the aflatoxin
pathway genes, while 22.22% isolates were aflatoxigenic, which included only the section
Flavi isolates. Section Flavi isolates identification was confirmed by calmodulin gene. The
presence of species from Aspergillus section Flavi and section Nigri indicate the potential
for aflatoxin or ochratoxin in the cashew nuts. The study established a foundation for future
investigations of the fungi and mycotoxins contaminating cashew nuts in Kenya, which
necessitates developing strategies to prevent infection by mycotoxigenic fungi, especially
during the storage and processing phases.
DArTseq-based silicoDArT and SNP markers reveal the genetic diversity and population structure of Kenyan cashew (Anacardium occidentale L.) landraces
(PLOS one, 2025-01-31) Dennis Wamalabe Mukhebi, Pauline Wambui Gachanja, Diana Jepkoech Karan, Brenda Muthoni Kamau , Pauline Wangeci King’ori , Bicko Steve Juma2,3 , Wilton Mwema Mbinda 1,2 *
Cashew (Anacardium occidentale L.) is an important tree grown worldwide for its edible fruits, nuts and other products of industrial applications. The ecologically sensitive
cashew-growing region in coastal Kenya is significantly affected by rising temperatures,
droughts, floods, and shifting rainfall patterns. These changes adversely impact cashew
growth by altering flowering patterns, increasing pests and diseases, and causing postharvest losses, which ultimately result in reduced yields and tree mortality. This is exacerbated by the long juvenile phase, high heterozygosity, lack of trait correlations, large
mature plant size, and inadequate genomic resources. For the first time, the Diversity
Array Technology (DArT) technology was employed to identify DArT (silicoDArT) and
single nucleotide polymorphisms (SNPs) markers for genomic understanding of cashew
in Kenya. Cashew leaf samples were collected in Kwale, Kilifi and Lamu counties along
coastal Kenya followed by DNA extraction. The reduced libraries were sequenced using
Hiseq 2500 Illumina sequencer, and the SNPs called using DarTsoft14. A total of 27,495
silicoDArT and 17,008 SNP markers were reported, of which 1340 silicoDArT and 824
SNP markers were used for analyses after screening, with >80% call rate, >95% reproducibility, polymorphism information content (PIC ≥ 0.25) and one ratio (>0.25). The
silicoDArT and SNP markers had mean PIC values ranging from 0.02–0.50 and 0.0–0.5,
with an allelic richness ranging from 1.992 to 1.994 for silicoDArT and 1.862 to 1.889 for
SNP markers. The observed heterozygosity and expected values ranged from 0.50–0.55
and 0.34–0.37, and 0.56–0.57 and 0.33 for both silicoDArT and SNP markers respectively.
Understanding cashew genomics through the application of SilicoDArT and SNP markers
is crucial for advancing cashew genomic breeding programs aimed at improving yield and
nut quality, and enhancing resistance or tolerance to biotic and abiotic stresses. Our study
presents an overview of the genetic diversity of cashew landraces in Kenya and demonstrates that DArT systems are a reliable tool for advancing genomic research in cashew
breeding
Camel milk products beyond yoghurt and fresh milk: challenges, processing and applications
(© Association of Food Scientists & Technologists (India) 2023, 2023-01-09) Philip K. Marete · Alfred M. Mariga· Guyo Huka · Levi Musalia · Eunice Marete · Julius M. Mathara · Joshua M. Arimi
Camel (Camelus dromedarius and (Camelus bactrianus) are commonly domesticated in the arid and
semi-arid regions because they are well adapted to live in
harsh climatic conditions. Camel milk is widely consumed
in these regions due to its high nutritional value and medicinal properties. It is rich in protein, minerals and vitamins.
Moreover, it possesses therapeutic properties such as antimicrobial, anti-oxidants, anti-viral and anti-cancer. Camel
milk can be processed into value added products with the
aim of extending shelf life and diversifying its usage. However, there are various challenges experienced in processing of camel milk products. This study aims at reviewing
published literature on camel milk products processing,
processing challenges, the available solutions and applications. To achieve these aims, literature search was carried
out using narrative methodology. Literature review provided
information concerning processing of camel milk products,
the challenges, how to overcome these processing challenges
and applications. From this review of literature on camel
milk products it can be concluded that it’s possible to process these products with some challenges but scientific and
technological solutions are available that are improving over
time.
