Some of the department members celebrated Ms. Patricia P. Ngoda achievement and conferred her Master’s in Tropical Animal Production on the Department Lawn Garden.
MS. Patricia Peter Ngoda successfully completed her Master’s Degree in Tropical Animal Production from Sokoine University of Agriculture on the 23rd of November 2023 Graduation Ceremony. The title of her Master’s Thesis is “Assessment of Bull Semen Quality Collected from National Artificial Center, Arusha Tanzania”, Ms. Patricia was supervised by Dr. Isaac P. Kashoma and Dr. George M. Msalya.
MAdam Mwadawa M. Kitale (Office Management Secretary) from the left, and Dr. Hieromin A. Lamtane (Senior Lecturer) on the right, Sandwiched Ms. Patricia P. Ngoda with her Graduation Cake, to mark the appreciation for her hard work during the persuasion of Master’s degree studies.
Summary of her Research Studies
Tanzania ranks second in terms of Cattle population in Africa of which 96.5% of cattle are indigenous breeds grazed on natural pasture under communal grazing lands and 3.5% are improved ones kept under semi-intensive and intensive livestock keeping systems. Livestock contribution to gross domestic product (GDP) is about 7.1% with an annual growth rate of five percent. The cattle industry is constrained by several challenges including climate change, low genetic potential of indigenous cattle, poor animal nutrition, animal diseases, and water shortage. To improve milk production, assisted reproductive biotechnologies such as Artificial Insemination (AI) is worldwide used for genetic improvement of dairy cattle.
In Tanzania, AI services started in the 1950s which was followed by the establishment of the National Artificial Insemination Centre (NAIC) at Usa River, Arusha in 1982 with the mandate of supplying the majority of AI semen used in the country. However, information regarding semen quality, produced, efficiency of semen preservation at NAIC and under field is limited. Therefore, the present study aimed to assess semen quality parameters during production and along the cold chain.
The first part of this research involved the collection of semen from 15 breeding bulls (Holstein Friesian = 4, Ayrshire = 4, Jersey = 3, Simmental = 2, and Boran = 2) once per week for five consecutive months. Semen was collected using artificial vagina and assessed volume (VOL) and then subjected to CASA system to determine sperm concentration (SPC), progressive motility (PM), total motility (TM), sperm viability (SPVI), sperm morphology/normalcy (SPNR), sperm velocity (VR), mucus penetration (MP), and sperm hyperactivity (HP). The second section of the study involved retrieving data originating from 1652 semen production records for the period of 2018 to 2021 at NAIC, and 540 cryopreserved bull semen (60 straws cryopreserved at NAIC and 480 straws retrieved back from distribution points and AI technicians spaced in different locations of Tanzania).
Cryopreserved semen were first thawed and analyzed using CASA system for sperm viability, spermatozoa kinetics (total and progressive motility, and straight-line velocity), mucus penetration, and hyperactivity. All the statistical analyses were done using Analysis of Variance (ANOVA) and the results were expressed as mean ± standard error of the mean using a statistical analysis system (SAS, 2004). Results for fresh semen quality parameters showed that ejaculate volume, progressive motility, total motility, sperm viability, and morphology were significantly (P< 0.05) affected by age and collection period. Simmental, Friesian, and Ayrshire bulls produced more voluminous semen than Jersey and Boran bulls. Jersey bulls had higher (P<0.05) sperm concentrations and live spermatozoa as compared to other bulls. Boran and Jersey’s bulls exhibited higher PM and TM than the other bulls.
The period of semen collection (morning versus evening) negatively affected semen volume, total motility, and semen viability in which morning harvests performed better than evening collections. Middle-aged bulls (3-5 years) produced semen of higher quality compared to other groups (< 3 years and > 5 years old bulls. Regarding retrieved data and cryopreserved semen, all semen traits (VOL, SPC, PM, TM, PM, TM, VER, MP and HP) were significantly (P<0.05) affected by season and cold value chain. During the cold season, the highest values of SPC, PM, TM, PM, TM, VER, MP and HP were observed as compared to that of the warm season. Furthermore, semen quality decreased gradually from pre-state (before freezing) to post-state (after freezing for 48 hours) with minor affection for semen motility. There was a higher decrease (p<0.05) in quality from cryo-stored semen straw to those of the same batch retrieved back from the field.
In conclusion, age, breed, period of semen production and ejaculate number revealed a significant effect on bovine semen characteristics. Also, semen were of high immediately after collection, satisfactory for those kept at NAIC, but of poor quality which were retrieved from the field. Observed unsatisfactory semen quality from field samples could be attributed by the poor handling, leakage of storage and transportation containers and sometimes the delay of refilling the LN2.
Ms. Patricia Peter Ngoda, soon after conferred her Masters Degree at Sokoine University of Agriculture
Associated Publications
Ngoda, P., Kashoma, I. and Msalya, G., (2023). A Semen quality of progeny-tested breeding bulls maintained at the National Artificial Insemination Centre, Arusha, Tanzania. East African Journal of Science, Technology and Innovation, 4(3).
Ngoda, P.P., Kashoma, I.P., Msalya, G.G. and Nguluma, A.S., (2023). The Quality of Cryopreserved Dairy Bulls Semen along Supply-Chain Used for Artificial Insemination in Tanzania. European Journal of Agriculture and Food Sciences, 5(5), pp.54-59.
Congratulations Ms. Patricia P. Ngoda for this great achievement
The Department of Animal, Aquaculture, and Range Sciences
The College of Agriculture, Sokoine University of Agriculture
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