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Aim:The aim of this study was to investigate the effect of nutritional status of the Gudali cows slaughtered at the Ngaoundere abattoir on follicular population, quality, and oocytes yield.Materials and Methods:Blood and ovaries were collected from 81 cows aged 6.35±0.24 years (3-12 years old), with a body condition score (BCS) of 2.93±0.09 (1-5). In each ovary, the follicle were counted and classified as small (<3 mm), medium (3-8 mm) and large (>8 mm) using an electronic caliper. Oocytes were collected by slicing technique and classified according to the homogeneity of the cytoplasm and layers of granulosa into four groups: I, II, III, and IV. The nutritional status of the animals was determined by quantification of serum glucose, total cholesterol, total protein, albumin, globulins, urea, and phosphorus level.Results:Of the total 162 ovaries harvested, 2916 follicles were counted on the ovarian surface with an average population of 36.00±2.17 follicles/cow. According to a size distribution, 16.67±1.54 (46.3%), 18.83±1.27 (52.3%), and 0.51±0.07 (1.4%), respectively for small (<3 mm), medium (3-8 mm), and large (>8 mm) were recorded. About 1,929 oocytes were obtained, with an average recovered of 23.81±1.53 oocytes/cow. Depending on the quality, 7.79±0.55 (32.7%), 6.04±0.41 (25.3%), 4.89±0.44 (20.6%), and 5.10±0.54 (21.4%) oocytes qualities I, II, III, and IV were obtained respectively; with an average cultivable oocyte recovered of 13.83±0.89 (58%). Cows with BCS > 3 and a high albumin and phosphorus level showed a highest number of follicles and oocytes able for in vitro maturation.Conclusion:These results indicated that nutrition remains an important factor for the in vitro production of the good embryo and the BCS is a useful tool for the selection of females’ oocytes donors.

Background Tsetse flies are cyclical vectors of African trypanosomiasis. They have established symbiotic associations with different bacteria, which influence certain aspects of their physiology. The vector competence of tsetse flies for different trypanosome species is highly variable and is suggested to be affected by various factors, amongst which are bacterial endosymbionts. Symbiotic interactions may provide an avenue for the disease control. The current study provided the prevalence of 3 tsetse symbionts in Glossina species from Cameroon, Chad and Nigeria.Results Tsetse flies were collected from five different locations and dissected. DNA was extracted and polymerase chain reaction PCR was used to detect the presence of Sodalis glossinidius, Spiroplasma sp and Wolbachia using specific primers. A total of 848 tsetse samples were analysed: Glossina morsitans submorsitans (47.52%), Glossina palpalis palpalis (37.26%), Glossina fuscipes fuscipes (9.08%) and Glossina tachinoides (6.13%). Only 95 (11.20%) were infected with at least one of the 3 symbionts. Among the infected, 6 (6.31%) were carrying mixed infection (Wolbachia and Spiroplasma). The overall symbiont prevalence was 0.88%, 3.66% and 11.00% respectively, for Sodalis, Spiroplasma and Wolbachia. Prevalence varied between countries and tsetse species. No Spiroplasma was detected in samples from Cameroon and no Sodalis was found in samples from Nigeria.Conclusion The present study revealed for the first time, the presence of infection by Spiroplasma in tsetse in Chad and Nigeria. These findings provide useful information to the repertoire of bacterial flora of tsetse flies and incite to more investigations to understand their implication in the vector competence of tsetse flies.

Background: To improve vector control of tsetse transmitted trypanosomiases through a better understanging of the vectorial competence of tsetse flies, investigations have been undertaken on the bacterial fauna of different tsetse species. It is in this light that Wolbachia and Sodalis glossinidius were detected in wild populations of Glossina morsistans submorsistans caught in the area of lake Iro in the south of Chad with the aim of generating data that may help to understand the influence of these symbiotic microorganisms on the vectorial competence of G. m. submorsistans. Methods: Tsetse flies were captured using biconical traps. DNA was extracted from tsetse body using the resin chelex. Sodalis glossinidius and Wolbachia were investigated by PCR using specific primers for pSG 2 and wsp genes. Comparisons between S. glossinidius and Wolbachia infections were performed according to sex and sampling periods and association studies between trypanosome infections and S. glossinidius or Wolbachia were performed. Results: From 345 G. m. submorsitans analyzed, 9.0% and 14.5% were respectively infected with S. glossinidius and Wolbachia. Only 2.31% of all tsetse flies hosted the 2 bacteria. Of all trypanosome-infected flies, 7.1% and 9.8% hosted respectively S. glossinidius and Wolbachia. No association was observed between Wolbachia and trypanosomes while significant association (r = 4.992; P = 0.025) was found between S. glossinidius and trypanosome infections. Although significant association (r = 3.147; P = 0.043) was observed between S. glossinidius and T. simiae, none was found with T. congolense or T. godfreyi. Conclusion: This study revealed S. glossinidius and Wolbachia in wild population of G. m. submorsitans of lake Iro. It showed that few tsetse flies are co-infected by Wolbachia and S. glossinidius. The presence of S. glossinidius seems to favor trypanosome infections while Wolbachia has probably no effect. Decrypting the tripartite association requires to investigate the relationship between haplotypes or genotypes of Wolbachia and/or S. glossiniduis and trypanosome infections.