Veterinary Obestrics and Gynaecology

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Modulation of ovarian function to improve suitability for reproductive biotechnology application in local and crossbred Cattle
(Addis Ababa University, 2022) Tilaye Demissie; Prof. Alemayehu Lemma; Dr. Tefera Yilma; Dr. Tamrat Degefa
Ovarian function is influenced by various intrinsic and extrinsic factors. Breed related variations, nutrition; local environmental conditions are among the major sources of differences in response to application of reproductive biotechnologies. It is of paramount importance to understand specific ovarian functions amenable to modifications in order to improve suitability for advanced technologies such as fixed time artificial insemination (FTAI), ultrasound guided ovum pickup (OPU) and in vitro embryo production (IVP). In the first part of this study, estrus sign/s that best correlate with the time of ovulation and pregnancies rate to insemination at FTAI was evaluated in 27 Boran*Holstein crossbred dairy heifers. The second part explored ovarian response to estrus synchronizing hormones by cow realated factors and pregnancy rate to FTAI after ovulation synchronization using GnRH and PGF2α with or without progesterone augmentation (CIDR vaginal insert) in native Borans and Boran*Holstein crossbred dairy cows. The third part assessed the effect of CL, follicle ablation, administration of different doses/frequency of FSH, and different coasting period in Boran cows. Result indicated that, the frequency of occurrence of various estrus signs, length of estrus, and onset of estrus, was not affected (P>0.05) by estrus type. Irrespective of estrus type, standing estrus (r=1, P<0.05), and mounting other heifers (r=0.87, P<0.05) showed a strong positive correlation with ovulation time. Ovulation rate and pregnancy rate on day 32 was significantly higher (P<0.05) in cows that received CIDR augmentation to the double GnRH and PGF2α protocol compared to those that did not. When time of insemination was considered conception rate to insemination 19h post second GnRH administration was significantly higher (P<0.05) for Ovsynch group compared to Cosynch group. Presence of CL did not influence mean number of follicles aspirated, oocyte recovery rate, and quality of oocyte and cleavage rate. Divided dose of 175 IU FSH and 350 IU FSH ignificantly (P<0.05) improved the mean number of medium and large follicles compared to single dose while the 48h coasting period significantly improved (P<0.05) oocyte grade, oocyte maturation rate and cleavage rate. It could be concluded that standing estrus best predict ovulation time. Insemination scheduled at 19h of standing estrus significantly increase conception rate as this sign best correlates with the mean time of ovulation. Further, CIDR priming to the synchronization protocol greatly improve ovulation rate and subsequent pregnancy. Follicular ablation and administration of divided doses of FSH prior to OPU and a coasting period of just 48hr improves follicular population and oocyte recovery rate. Hwever, future studies are recommended to answer why Boran cows’ with morphologically smaller CL than Boran*Holstein cows have larger amount of progesterone than Boran*Holstein. Why some heifers that ovulated to D0 GnRH did not ovulate to D9 GnRH. As some of the CL that were present at day of start were lost at PGF2α the effect of stages of estrus cycle at the start of hormone treatment shoud be assessed both in Boran and Boran*Holstein cattle.
Bovine Viral Diarrhea Virus (BVDV) Exposure in Dairy Cattle in Southern and Central Ethiopia and Potential Association with Reproductive Performance
(Addis Ababa University, 2022) Kassaye Aragaw; Prof. Fekadu Regassa; Prof. Kassahun Asmare
Bovine viral diarrhea virus (BVDV) is an important viral pathogen of cattle with a worldwide distribution. Although infection with the virus is usually subclinical, it may cause wideranging clinical conditions in cattle. Its main economic significance results from its effect on reproductive performance of cattle. It causes embryonic mortality and absorption, abortion, stillbirth, fetal malformation and birth of weak calves depending on stage of pregnancy during infection. In cetain outbreaks it may cause severe morbidity and mortality in susceptible herds depending on the strain of the virus. Despite the economic importance of the virus in almost every major cattle producing countries of the world only few studies have so far been conducted in Ethiopia. Those few works were also mostly limited to serological studies in limited geographic areas. There is lack of reports regarding occurrence of active disease or outbreaks associating infection with clinical conditions and losses. There is also so far no published work on the genotype of the virus prevalent in the country. Therefore this study was designed with aims to estimate the seroprevalence, identify associated risk factors and assess association of BVDV serostatus with reproductive wastage in dairy cows in Ethiopia. The study also attempted to detect and characterize BVDV nucleic acid in samples collected from bovine abortions and sera collected from selected animals. Accordingly, sera were collected from 954 randomly selected cattle from 98 dairy herds in southern and central Ethiopia. These sera samples were tested for BVDV antibodies using a commercial ELISA. Fetal tissue samples and placenta from 30 bovine abortions and sera from 26 selected cattle were also collected for detection of BVDV nucleic acid using reverse transcription (RT)-PCR. Among screened sera samples 20.9% (95%CI, 18.4, 23.6) were tested positive to BVDV antibodies. The herd prevalence was 50% (95%CI, 40.1, 59.9) and the intra-herd prevalence ranged between 2.6% and 100% (mean = 31.4%) in positive herds. Geographic region, herd size and animal arrangement in the farm had significant association with serostatus (p <0.05). Cattle from southern Ethiopia and herds of large size had 2.8 (95%CI; 1.9, 4.2) and 2.6 (95%CI; 1.5, 4.6) times higher odds of being seropositive compared to their counterparts, respectively. Serostatus to BVDV was associated with history of anestrus, repeat breeding (RB), mastitis and extended calving interval (CI) (p <0.05). Animals with history of extended CI and mastitis were 1.7 (95%CI; 1.0, 2.7) and 2.2 (95%CI; 1.5, 3.2) times more likely to be seropositive compared with those with normal CI and no history of mastitis, respectively. On the other hand, animals with history of anestrus and RB were less likely to be seropositive to BVDV compared to cattle with no such history. All samples tested with RT-PCR were negative for BVDV nucleic acid. Our study highlights the association of BVDV infection with some important reproductive performance traits and potential risk factors. The study also demonstrated high occurrence of reproductive health problems in dairy cattle in Ethiopia and that the reproductive performance of dairy cattle in the study herds is suboptimal.
Quality of semen and its implication on fertility of breeding bulls: a multiparametric analysis using computer assisted semen analyzer and functional tests of semen produced at livestock development institute
(Addis Ababa University, 2022) Kefelegn Seyoum; Prof. Alemayehu Lemma
Various factors are believed to influence the quality of semen in breeding bulls. Among them breed, bull selection and management, diseases and evaluation methods are believed to be the most important one. Poor semen evaluation, such as used in the conventional methods that do not address aspects of the complex spermatozoon structure and subsequent fertilization process implies the production of semen with low conception rate compromising success of artificial insemination. Reports confirm that the Ethiopian Livestock Development Institute (LDI) uses the conventional method and produces semen characterized by low conception rate. A multiparametric semen evaluation using advanced technology and functional tests that sets a higher standard for approval would improve the quality of semen. Accordingly, a computer based integrated semen analysis system, and acrosomal and plasma membrane integrity tests were applied on semen collected from 14 breeding bulls (Boran = 4, Boran* Holstein Frisian Crosses = 4 and Holstein Frisian = 6). Bulls were additionally investigated for incipient general and reproductive diseases. After the initial conventional assessment, semen was evaluated using advanced multiparametric method at fresh, chilled and frozen stages for various semen quality parameters. There were significant (P < 0.05) breed differences between Boran and Holstein Frisian breeds in scrotal circumference (33.20 Vs 38.40cm), testes volume (254.40 Vs 367.50cm3), testes weight (264.10 Vs 381.40g), semen volume (9.81 Vs 11.39ml), pH (6.31 Vs 6.58), spermatozoa head abnormality (5.02 Vs 3.42%), Hypo osmotic swelling reactivity (39.55 and 49.46%) and acrosome intact live spermatozoa (43.29 and 49.67%), respectively. Total sperm morphological abnormality (18.10%) were significantly (P < 0.05) higher in the Crosses. Motility was significantly higher (82.5%, P < 0.05) in fresh Boran semen while the same parameter was higher in chilled (70.2%) and frozen (42.9%) semen from HF bulls. All kinematic parameters (VCL, VAP, VSL, ALH, BCF, LIN, STR, and WOB) were significantly different (P<0.05) at all stages of semen production among the three breeds, being lower for Cross breed bulls. The ISAS method and the functional tests applied in this study invalidated some of the values of sperm parameters from the conventional method. Moreover, results of HOST, acrosome integrity and sperm morphological defects were associated with one or more of sperm motion characteristics which were not revealed if only conventional method was used. With minimum cut-off values (total motility=40% and progressive motility=15%) in frozen semen, nearly 56% of semen produced at LDI failed to fulfill the minimum approval requirements by ISAS. This was very apparent in semen of Cross bulls for both parameters (total motility 33.1 Vs 12.9% progressive motility) and to that of total motility (33.9%) in Boran semen. All bulls investigated were found to have no general and/or reproductive health problems that influenced the quality of semen. It is therefore plausible to assume that poor semen quality resulting from absence of a more rigorous evaluation method could be one of the factors contributing to the low conception rate at the field level. The significance of introducing advanced methods of semen evaluation is incontrovertible; however, this finding has to be complemented with more field studies and investigation of risk factors in the female individual to get a complete picture. As LDI is bearing a huge national responsibility in advancing the cross breeding program based on AI, it becomes invariably mandatory to start using state of the art methods of breeding soundness examination and semen evaluation.
Ovarian follicular dynamics and conception rate in Boran cows previously subjected to repeated ovum pick up
(Addis Ababa University, 2021) Gezahegn Berhan; Dr. Tefera Yilma; Dr. Tilaye Demissie
The study was conducted to investigate the effect of repeated ovum pick-up on ovarian follicular dynamics, serum estrogen and progesterone pattern, and the conception rate of Boran cows. Eight Boran cows were estrous synchronized by 500μg PGF2α at 11 days intervals. After the second PGF2α injection ovaries were scanned by transrectal ultrasonography every 12 hrs for the first two days and then every 6 hrs until ovulation. From the day of ovulation onwards, the ovaries were examined twice daily (at 12 hrs interval) to characterize the growth and regression pattern of ovarian follicles during two consecutive estrous cycles. A blood sample was collected every other day to evaluate estrogen and progesterone concentrations. The mean (±SEM) IOI was 21.1±1.19 days for cows with two waves and 22.66±0.57 days for cows with three waves. The length of the IOI was not significant (P>0.05) by follicular waves. The mean (±SEM) number of days from the emergence of cohort follicles to ovulation of dominant follicle of the ovulatory wave was significantly (P<0.05) greater (10.80±1.03 days) for two wave cows than three-wave cows (7.50±0.70 days). The mean (±SEM) diameter of the preovulatory follicle was significantly (P<0.05) larger for cows with two waves (14.29±1.36mm) than for cows with three waves (12.30±1.01mm). The mean (±SEM) growth rate of the dominant follicle that finally ovulated was significantly (P<0.05) higher (1.16±1.2mm/day) in the three-wave cycle than in two-wave cycles (0.85±0.1mm/day). The mean (±SEM) serum concentrations of estrogen and progesterone were 28.73±6.56 pg/ml and 0.88±0.40 ng/ml, respectively during the proestrous and estrous. While during the late diestrous cycle, serum estrogen and progesterone were 11.01±1.61pg/ml and 2.67±0.12 ng/ml, respectively. 87.5 % of cows were found conceived on ultrasound 32 days after insemination. In conclusion, based on ovarian follicular dynamics, serum estrogen and progesterone pattern, and conception rate repeated ovum pick does not significantly affect the fertility of Boran cows. Boran cows were characterized by a higher incidence of two-wave cycles.
In vitro maturation of oocytes retrieved through transvaginal oocyte aspiration from Boran and Boran *Holstein Friesian crossbred cows
(Addis Ababa University, 2021) Asnaku Funga; Prof.Alemayehu Lemma; Dr. Jeilu Jemal
The developmental competence of immature oocytes largely depends on the origin and method of retrieval. This is known to determine the success of in vitro embryo production. This study aimed to evaluate the in vitro maturation difference of oocytes from pure Boran and Holstein Friesian*Boran crossbred cows obtained through ovum pickup. The OPU was carried out on 10 cows, 5 cows from each breed. The overall oocyte recovery rate was 43.4% (288/663); 39.3% (131/333) for Boran and 47.6% (157/330) for Crossbred with no breed influence (p>0.05). Oocytes aspirated from the 288 follicles (all ≥ 3mm) were matured in either TCM-199 or BO-IVM maturation mediums. Proportion of viable oocytes were comparable between Boran (81.60%) and B*HF crossbred (78.9%). The mean number of oocytes collected per ovum pickup session for Boran and Crossbred cows were 2.18 ± 1.90 and 2.62 ± 1.86, respectively. The overall maturation rate was in the order of 79.4% and 79% for Boran and crossbreeds, respectively, and comparable between the breeds. Considering all maturation indices, oocyte maturation was significantly higher (p<0.05) in BO-IVM (88.5%) compared to TCM-199 (70.4%). Maturation of Boran oocytes in BO-IVM was relatively higher (90.3%) compared to Boran*HF oocytes (86.2%); whereas it was 73.1% for Boran and 68.2% for Boran*HF oocytes in TCM. Maturation rate in terms of cumulus cell expansion was relatively better in BO-IVM (59.3% fully expanded and 30.1% partially expanded) compared to TCM-199 (46.9% fully expanded and 24.4% partially expanded). Overall, there was extrusion of the polar body in 55.75% of oocytes and increased perivitelline space in 69.2% of oocytes. Zona quality was relatively better in BO-IVM (69.2% of oocytes) compared to TCM-199 medium (60.9% of oocytes). In conclusion, oocyte maturation following OPU was influenced by media type but not by breed. It can also be concluded that some of the maturation indices were more affected by breed and media type even though the overall maturation was closely similar.
Association of Subclinical Mastitis and Lameness with Reproductive Performance and Subclinical Endometritis in Zebu X Friesian Crossbred Dairy Cows In And Around Jimma Town Dairy Farms, Ethiopia
(Addis Ababa University, 2023) Nuraddis Ibrahim; Prof. Fekadu Regassa; Dr. Tefera Yilma; Prof. Tadele Tolosa
A longitudinal observational study was conducted to assess the association of subclinical mastitis and lameness with reproductive performance and subclinical endometritis in crossbred dairy cows. The California Mastitis Test and cytobrush technique were used to screen for subclinical mastitis and subclinical endometritis, respectively. Samples positive for subclinical mastitis were subjected to bacteriological analysis. Lameness in cows was also assessed using a 5-point locomotion scoring system. Analysis of progesterone and cortisol concentrations in blood serum of cows was performed using electrochemiluminescence immunoassay “ECLIA”. A total of 84 clinically healthy cows were tested for subclinical mastitis using the California Mastitis Test. The prevalence of subclinical mastitis at cow level was 51.2% (43/84). The prevalence of subclinical mastitis in 108 lame cows was 53.7% (58 of 108). Based on the results, the 192 cows according to the study were divided into the following four groups: Group I (n=43) cows with subclinical mastitis, Group II (n=50) are lame cows, Group III (n=58) lame cows with subclinical mastitis and Group IV (n=41) healthy cows (control group). Lame cattle are also classified as no lameness, mild lameness, moderate lameness, lameness, and severe lameness. Mean number of days from calving to first mating interval was highly significantly longest in lame cows with subclinical mastitis (122.71±28.6) than for lame cows (120.98±31.3), subclinical mastitis cows (120.51±24.5) and healthy cows (85.15±28.3) (P<0.05). Mean number of services per conception was significantly highest in lame cows with subclinical mastitis (3.66±1.31) than lame cows (3±1.6), subclinical mastitis cows (2.51±0.83) and healthy cows (1.59±0.81) (P<0.05). Cows clinically lame had a longest calving to first service interval when compared with cows which were never lame and those mildly lame. The difference was significant (P<0.05). Lowest conception and pregnancy rates at first services were observed in lame cows with subclinical mastitis. Cows that were clinically lame had a lowest conception rate at first services than cows that were never lame and mildly lame, although the difference was not statistically significant (P>0.05). Clinically lame cows had a lowest pregnancy rate at first services than cows that were never lame and mildly lame (P<0.05). Risk factors analysis revealed that prevalence of subclinical mastitis, lameness and in lame cows with subclinical mastitis significantly differed with the parity and body condition score (P<0.05). The present study revealed that subclinical mastitis and lameness were significantly and directly associated with subclinical endometritis (P<0.05). Progesterone concentrations highly decreased in lame cows with subclinical mastitis than in subclinical mastitis and lameness alone while the cortisol concentrations also highly increased in lame cows with subclinical mastitis. The major bacterial isolate was Staphylococcus aureus. In conclusion these results provide further evidence that combined occurrence of subclinical mastitis and lameness inflict harmful effects on fertility and hormonal profiles of dairy cows than those diagnosed with mastitis and lameness alone, emphasizing the relevance of mastitis and lameness control programs in dairy farms.
The Impact of Periparturient Disorders, Mastitis, and Lameness on Reproductive Performance of Dairy Cows in Selected Districts of Wolaita Zone, Southern Ethiopia
(Addis Abeba University, 2023) Gizaw Mekonnen; Prof. Fikadu Regassa; Prof. Gebeyehu Goshu
A cohort study using retrospective data from 2020 to 2022 was conducted to determine the impact of periparturient disorders, mastitis, and lameness on the reproductive performance of dairy cows in selected districts of Wolaita Zone, Southern Ethiopia, from November 2022 to April, 2023. The retrospective cross-sectional study was conducted to determine the prevalence of disorders. Multi-stage purposive sampling was used to select districts and dairy farms. Retrospective data on 1326 dairy cows was collected from 40 dairy farms. Logistic regression, chi-square, and t-test were used to analyze the data. Based on the analyzed data, 40.20% (533/1326) of dairy cows were affected by at least one disorder. The prevalence of the disorders that include endometritis, retained placenta, dystocia, hypocalcemia, mastitis, and lameness accounted 14.33%, 9.58%, 9.58%, 8.60%, 13.12%, and 10.56%, respectively. The occurrence of periparturient disorders, mastitis, and lameness showed statistically significant difference (p <0.05) with regard to body condition, parity, age, and calving season. Although the location of the farm had no significant effect on the occurrence of mastitis and lameness, it was a significant environmental factor for the occurrence of periparturient disorders. Dairy cows calving from June to August had a high probability of being affected by periparturient disorders and mastitis. Lameness was more common from September to November. In the current study; periparturient disorders, mastitis, and lameness had a strong negative impact on the calving-to-conception interval, calving-to-first service, and number of services per conception, but dystocia had no significant impact on the calving-to-first-service interval. Moreover, lameness had a significant impact on age at first calving, but it had no impact on age at first service. The first-service conception rate was higher in normal dairy cows than diseased cows (p<0.05). Thus, Periparturient disorders, lameness, and mastitis had an impact on the reproductive performance of dairy cows in the study area. It is recommended that proper feeding, husbandry, udder health, and foot care of dairy cows during the transition period need to be implemented. Early detection of disorders is essential to minimize the reproductive consequences of health problems.
Prevalence, Major risk factors and Response to Hormonal therapy of Phantom Cow Syndrome in urban/peri-urban dairy farms in Bishoftu town
(Addis Ababa University, 2023) Onneta Regasa; Prof. Alemayehu Lemma; Dr. Tilaye Demissie
Phantom cows that are non-pregnant and not returning to estrus within 21-24 days post insemination cause a serious reproductive management challenge for the smallholder and huge economic loss for the dairy producer. A clinical survey and therapeutic experimental study were conducted to determine the prevalence of phantom cow syndrome, determination risk factors and possibility of treatment using reproductive hormones in 25 dairy farms in and around Bishoftu town. Relevant data were collected through clinical evaluation of animals, record analysis reproductive indices and experimentation. The overall incidence of phantom cow syndrome was 11.9%; (86/720). Proportional incidences in small, medium and large farms were 47.5%, 11.8% and 5.8%, respectively. There was a significant difference (P < 0.05) between the different farm sizes. Presence of diseases such as Pyometra, metritis, luteal cyst, and cow related factors such as daily milk yield, age, parity, and body condition were found to be the major risk factors of PCS. There was a significant difference (P<0.05) in the incidence of PCS with respect to age, herd size, and parity. Return to estrus and pregnancy were highly improved in treated phantom cows with relatively higher pregnancy rate (75%) observed when cows were treated with PGF2 alpha and uterine lavage when there is endometritis. Early pregnancy diagnosis (between days 17 and 24) either with ultrasound or non-pregnancy test using a rapid P4Gold test was instrumental in restoring cyclicity in phantom cows. The prevalence of PCS in this study is relatively high; showing more non-productive animals are being kept in the dairy system. Many of the risk factors identified in this study are more common in the small holder dairy farms thus need to be considered during optimizing the production system. The use of a more accurate method of early pregnancy detection and treatment of phantom cows with reproductive hormones can contribute to the reduction of incidence of PCS by increasing submission rate for cows that fail to be pregnant during the preceding service. Therefore, proper diagnosis of phantom cows and their early treatment using hormones can potentially reduce the overall impact of PCS
Study on Breeding Soundness and Fertility of Senar Jackass (Equus Asinus) in North Gondar,Amhara Region ,Ethiopia
(Debre Zeit, 2009-06) Tsega, Aweke; Lemma, Alemayehu PhD
This study was carried out with an objective of evaluating the breeding sundness, fresh and chilled semen.and fertility of Senar jackasses.The physical characteristies such as the body weight. Height. Body condition. and age of the jacks was measured and recorded.
Study on Prevalence of Major Gi Nematodiosis of Small Ruminants in Three Selected Sites of Afar Region ,Ethiopia
(Debre Zeit, 2008-06) Shiferaw, Dereje; Yacob, Hailu PhD
The current study was conductcd to determine thc prevalcncc of GIT nemntodcs of sheep and goats in three different districts of Afar Region from Octoher 2007 to April 2008.A total of 480 (180 sheep and 300 goats) animals were subjected to post mortem exnminations and 2314 fecal samples were analyzed usin g standard coprological techniques (flotation and modified McMaster faecal worm egg counts). Questionpaire surve'y was conducted in randomly selected 6 PA's and 60 households from three districts. Results from coprological examination rcvealed the overall prevalence of nematocies in sheep and goats was 55 %and 22.5 % respectively. During post mortem examination, of five nematode species (Haemonchus contotus,89.1%), (Oesophagostomum venulasum,
Ultrasonographic Studies on Ovarian Dynamics and Assciated Estrus Manifestations of Jennies Under Controlled Management
(Debre Zeit, 2008-06) Kebede, Hassen; Lemma, Alemayehu PhD
Serial ultrasonographic study was condueted on nine Jennies aged 5-14 years from December 2007 to April.2008 with the objective of characterizing ovarian follicular activities and estrus manifestations under controlled management.The jennies were housed, fed on hay and concentrate, regularly watered and were not working during the study.Ovarian follicular activity was derermined from number and size distribution of follicles.
Ulrasonographic Studies on Ovar Dynamics and Associated Estrusman Festations of Jennies under Controlled Management
(Addis Ababa University, 2008-06) Kebede, Hassen; Tolera (ph.D), Adugna
Serial Ultasonograhpic Study was Condcted on nine Jennies GED 5-14 YEARS FROM Dember 2007 to April
Quality of in Vivo Produced Embryos from Boran and Holstein Breeds with Alternate Sire and Dam Combination in Dairy Animals under Controlled Environment
(2021-08) Hamid, Jemal; Prof. Alemayehu Lemma, Dr. Tamrat Degefa
The difference in dairy breed type can determine the success of bovine embryo transfer by influencing the quantity and quality of embryos during in vivo embryo production. This is particularly true since response to the superovulatory hormone treatments varies because of breed and doses of the hormone. In this study, the quantity and quality of embryos were evaluated for Boran and HF*Boran (50% and 75% cross breed) dairy cows alternatively using semen from HF and Boran sires. Total of 42 HF*Boran and HF cows were used to study superovulatory response, 33 HF*Boran cows for evaluation of estrus behavior and 36 HF*Boran and Boran dairy cows for evaluation of embryo quality as three separate experiments. In experiment one, three different dosages of Pluset® (FSH hormone) (500 IU, 650 IU and 800 IU) were evaluated for their best response. In experiment two, types and strength of estrus behaviors were characterized as predictor of superovulatory responses. In experiment three, the donor dams and sires were alternatively used from different breeds to evaluate breed effect on qualities of embryos flushed on Day-7 post AI. In experiment one, the superovulatory response rate was significantly higher (P<0.05) in the HF*Boran than HF cows. The mean ± (SE) highest response based on CL count was 14.6 ± 1.1 and the lowest 11.0 ± 1.3, in HF*Boran, at Pluset® dose of 650 IU and 500 IU, respectively. In experiment two, the overall average time required for commencing estrus signs after CIDR removal was 37.4 ± 1.5 hrs and the duration of estrus was 28.5 ± 1.2 hrs. Behavioral estrus was weak in 48.5% (16/33), moderate in 39.4% (13/33) and strong in 12.1% (4/33) of cows regardless of the breeds. Cows with strong estrus behavior had significantly higher superovulatory response (p<0.05) and also vi produced a significantly higher (P=0.000, χ2=31.6) number of UFO than cows who had moderate or weak estrus. In experiment three, 88.9% of the Boran and 83.3% HF*Boran donors responded to the superovulation with no significant breed differences. Total recovery rate was relatively lower (56.5%) in Boran compared to crosses (67.4%). The mean (±SE) total flush output was 6.5±0.8 for Boran and 6.9±0.7 for HF*Boran with no significant breed difference. Mean (±SE) recovery of transferrable embryo was significantly higher (5.3 ± 0.8; p<0.05) in HF*Boran dams inseminated with HF sire semen. Boran cows yielded a significantly higher (p<0.05) proportion of UFO (3.6 ± 0.6) irrespective of the sire breeds. Boran cows inseminated with HF sire semen yield significantly higher proportion of G1 embryos (64.7%, n=22) while HF*Boran produced more G2 embryos (43.1%, n=25). This study demonstrated that doses of FSH determines the ovarian response and the presence of breed related differences in both the quality and quantity of in vivo produced Bovine embryos. Boran breed consistently produced higher proportion of UFO irrespective of the breed of sires while HF*Boran cows produced a significantly higher number of transferable embryos when inseminated with semen from HF sires. It concludes the significance of breed during selection of donors for a successful embryo transfer.
Estrus Response of Boran and Boran-Holstein Crossed Cattle to Pgf2α and Pregnancy Rates to Sexed and Conventional Semen, Holeta, Ethiopia
(2020-06) Galma, Boneya; Dr. Tefera Yilma, Dr. Tilaye Demissie
The study was conducted majorly to evaluate pregnancy rate to sex sorted semen and high grade non sex sorted imported semen in a 2X2 factorial design in Boran and Boran X Holstein cross cows and heifers. The effect of some animal related factors which may affect pregnancy rate and heat characteristics of different breeds and party were evaluated. A total of 71cows/heifers consisting of 36 Boran and 35 Boran x Holstein of which 49 were cows and 22 heifers were purposively selected and synchronized using PGF2, twenty five Boran (69.4%) and twenty seven Boran x Holstein cross (77.1) were responded to PGF2 and exhibited estrus. When response to PGF2 was compared by parity, 65.3% cows (n=32) and 90.9% heifers (n=20) exhibited estrus. Parity has statistically significant (P<0.05) effect on estrus response in which heifers showed higher response rate than cows whereas, breeds, body condition score and treatment (response at single or double PGF2) did not show significant effects on estrus response (P>0.05). Average duration of estrus was significantly longer in Boran x Holstein cross breed than Boran breed. However, average interval to onset of estrus and duration of standing estrus were not significant differ (P>0.05) by both breed and parity. A multivariable logistic regression model including the breed, parity, body condition score, treatment, semen type and their interactions was evaluated. Parity and semen type showed significant variation (P<0.05) on the pregnancy rate. On pregnancy detection, 54.1% Boran and 57.6% cross breed cattle were found pregnant of which 46.8% were cows and 72.2% were heifers to both types of semen. The pregnancy rate was 66.6% to conventional semen and 46.1% to sexed semen. It could be concluded that sexed semen could be a better option to improve number of replacement heifers. Similarly, high grade imported semen may help speeding up genetic improvement when used on Boran heifers. However, data from large number of animals should better be generated. Heifers were well responded to than cows; duration of estrus was longer in Boran breeds than crossbred and heifers was higher conception rates than cows.
EFFECT OF TRADITIONAL HUSBANDRY ON REPRODUCTIVE PERFORMANCE OF GOATS IN BENISHANGUL-GUMUZ REGION
(2008-06) YESHAWORK, BEGASHAW; Dr. Alemayehu Lemma
Study was conducted from October 2007 to April 2008 in six districts of two administrative zones of the Benishangul-Gumuz region to determine the reproductive performance of goats under traditional husbandry system. Structure questionnaire and a field clinical survey studies were used on a total of 200 randomly selected households. The entire goats owned by the households were clinically examined for the presence of any health problem. Records of animal identification, parameters of reproductive performance such as weaning age and age at puberty, litter size, KI, the type of management practice and clinical parameters were taken on pre-designed format. The type of management was measured from conditions of housing (absence or presence), feeding (presence of supplementation), and health (getting veterinary service). The level of management was categorized as poor, moderate and good according to Song et al., (2006). Accordingly, goats were primarily (68%) kept for income generation while some (26%) keep goats for both income generation and/or meat. The common housing practice was either poor (48.5%) or inexistent (51.5%). Feeding on natural pasture with supplementation (commonly maize, sorghum or kitchen waste) constitute 29% while the remaining 71% were known to exclusively depend on grazing. The major production constraints were health problems (53%); poor genetic potential (20.43%) and shortage of feed (20.32%). Generally, goats reached puberty at 6.5±1.22 (male) and 6.7±1.22 months (female). The mean (±sd) kidding interval was 252.35±31.46 days with a mean (±sd) litter size of 1.6±0.3. Annual reproductive rate was found to be 2.2kids/year. The mean (±sd) weaning age was 4.74±0.7 months. All animals were clinically examined on the basis of the history, inspection, palpation, percussion, auscultation and information was taken from each household during the study period. Out of 461 clinically examined animals the incidence of external parasitism, internal parasitism; reproductive diseases, and infectious diseases were in the order of 80.7 %, 23.2%, 16.1% and 22.8 %, respectively. The primary goat feed resource was natural pasture and river was a main source of water. The prevailing housing is rudimentary and difficulty for management of different categories of goats. Over all management level, especially health management and feeding regime were found to be the ix primary factors significantly affecting the reproductive parameters of goats. Kidding interval and weaning age were the most affected parameters by existing traditional husbandry in the study area.
ULTRASONOGRAPHIC STUDIES ON OVARIAN DYNAMICS AND ASSOCIATED ESTRUS MANIFESTATIONS OF JENNIES UNDER CONTROLLED MANAGEMENT
(2008-06) HASSEN, KEBEDE; Dr. Alemayehu Lemma, Prof. Merga Bekana
Serial ultrasonographic study was conducted on nine Jennies aged 5-14 years from December 2007 to April, 2008 with the objective of characterizing ovarian follicular activities and estrus manifestations under controlled management. The jennies were housed, fed on hay and concentrate, regularly watered and were not working during the study. Ovarian follicular activity was determined from number and size distribution of follicles, length of interovulatory interval, growth rate of preovulatory follicles, diameter of follicles at the onset of estrus and incidence of ovulation. Estrus manifestations were characterized using length of estrus and estrous cycle. The mean (± SD) number of follicle detected per ovary was 5.45 ± 2.25(range 1 -16) with sizes ranging from 2.88mm to 44mm.The mean (± SD) size of follicle encountered at the onset of estrus was 25.9 ± 3.7 mm (range 20.9 – 34.4) while that of the preovulatory follicles at -1 day before ovulation was 36.81 ± 3.78mm. The mean (± SD) interovulatory interval, estrus and estrous cycle length were 25.4 ± 3.6; 7.85± 2.99 and 24.22 ± 7.43 days respectively. The mean (± SD) growth rate of the preovulatory follicle after day of divergence, which fell on -8 day before ovulation was 1.89 ±0.33mm/day (P<0.001). Follicles were known to grow in cohorts constituting two or more waves. Serum progesterone profile followed the same patterns of ovarian dynamics with peak values being detected during mid luteal phase. Serum progesterone assay revealed blood progesterone profiles of <1.0 ng /ml during estrus and up to 11ng /ml during mid - luteal phase which has shown the presence of ovarian cyclicity through out the study period with patterns following follicular dynamics. Majority (82.14%) of the estrus manifestations were significantly (p<0.005) associated with ovulations. Body condition was positively correlated (r = 0.52, P< 0.001) with the diameter of the preovulatory follicle and negatively with the number of follicles per ovary (p<0.01). Estrus length was also found to be positively correlated to size of preovulatory follicle at onset of estrus (r = 0.412, p<0.05) and negatively correlated to interovulatory interval (r = -0.548, p<0.05). Ovarian follicular dynamics in jennies are generally equine prototype with subtle differences. In contrast to previous reports of reproductive activity under traditional management systems, this study confirmed as improved management can also improve the ovarian activity. However, it still remains to be verified as to see the relative and individual effects of management factors on follicular activity.
SUBCLINICAL ENDOMETRITIS AND ITS EFFECT ON REPRODUCTIVE PERFORMANCE OF CROSSBRED DAIRY COWS IN DEBRE ZEIT
(2007-06) BELACHEW, BACHA; Dr. Fekadu Regassa
In this study 59 postpartum crossbred dairy cows were selected from three different farming scales (smallholders, medium sized and large scale dairy farms). Each cow had a normal parturition and had no abnormal uterine discharge by vaginoscopy or no abnormality in rectal palpation. Then the cows were examined for subclinical endometritis by examination of endometrial lavage sample for the presence of neutrophils at the 4th and 8th weeks postpartum. The prevalence of cytologically diagnosed subclinical endometritis was 47.5% at the 4th and 30.5% at the 8th weeks of postpartum. In the three farming scales the prevalence of subclinical endometritis was 64.7% in small holders, 40.7% in medium sized and 40.0% in large-scale farms at the 4th week of postpartum (P = 0.240). While prevalence of 41.2%, 26.7% and 25.9% was recorded at the 8th week of postpartum (P = 0.526) in small, medium and large scale dairy farms respectively. Parity did not influence the prevalence of subclinical endometritis at the 4th week of postpartum (P = 0.492). Cytologically diagnosed subclinical endometritis was greatly associated with impaired reproductive performance. Cows that had subclinical endometritis at the 4th week postpartum required a mean of 2.4 services per conception compared to 1.7 services per conception for normal cows (P = 0.000) where as at the 8th week postpartum 2.7 services per conception were required for cows with subclinical endometritis, compared to 1.7 for normal cows (P = 0.001). For cows with subclinical endometritis at the 4th weeks postpartum the median calving to first service interval were 96 days and 80 days for normal cows (P = 0.000) while at the 8th week postpartum it was100 days for cows with subclinical endometritis and 82 days for normal cows. For cows with subclinical endometritis at the 4th weeks postpartum the median days open were 174 and 152 for normal cows (P =0.001) while at the 8th week of postpartum it was 178 for cows with subclinical endometritis and 155 days for cows without subclinical endometritis (P = 0.000). Also, there was a significant difference in first service conception rate between cows with and without subclinical endometritis at the 8th week of postpartum (3.4 versus 27.1%; P < 0.05). From those cows diagnosed negative for subclinical endometritis at the 8th week postpartum Proportionally 51% of cows confirmed to be pregnant with in 180 days, whereas from those positive cows for subclinical endometritis only 2% confirmed to be pregnant. The proportion of cows confirmed to be pregnant with in 180 days were 41 and 12% for normal cows and cows with subclinical endometritis at the 4th week of postpartum respectively. These results also indicated that there was an association between subclinical mastitis and IX subclinical endometritis at the 4th (P = 0.012) and 8th (P = 0.031) week of postpartum. From the follow up findings, it was observed that risk factors like poor body condition scores at the 4th week of postpartum had an association with subclinical endometritis (P = 0.017). Dairy cows with no regular exercise had a higher prevalence of subclinical endometritis than those exercising regularly (53.6 versus 46.4%; P = 0.026). In conclusion subclinical endometritis diagnosed by endometrial cytology in the postpartum period had a detrimental effect on current reproductive performance.
Comparison of Conception Rate of Frozen Semen from Two Extenders and Methods of Early Pregnancy Diagnosis Using Ultrasonography, And Progesterone Analysis in Dairy Cattle
(2019-06) Abiy, Shimelis; Alemayehu Lemma (Prof), Dr. Tilaye Demissie
Semen extenders used in Ethiopia are imported and expensive. Pregnancy detection is mostly through rectal palpation. This study was designed to compare conception rates of frozen semen prepared by commercial (Bioxcell) and homemade (Tris egg yolk) extenders. Further, evaluate advanced methods of early pregnancy diagnosis (18th to 22nd days post AI) using Progesterone analysis and Ultrasonography. Post-thaw semen viability, forward motility, live percent and morphological abnormality were 67±2.6%; 43.59±3.7%; 47.22±1.8% and 42.12±1.26% for TEY preserved semen, respectively; while the same parameters were 68.11±2.6%; 40.83±4.0%; 46.52±1.7% and 41.64±1.1% for Bioxcell preserved semen, respectively. HOS test was higher in TEY (8.87±0.72) extended semen than that of BioXcell extended semen (4.45±1.20%). A total 120 animals were included for both study, 48 animals for conception rate of semen extenders (14 heifers and 34 cows) were equally grouped and inseminated (24 by Bioxcell – G-I and 24 by Tris egg yolk – G-II). First service conception rate was 50% for G-I and 70.8% for G-II. Though conception rate was higher in G-II, there were statistically non significant but higher values between the groups. Nevertheless, conception rate was higher for both heifers and cows within G-II (71.42% and 70.58% in G-II compared to 42.85% and 52.94% in G-I). From a total of 72 animals inseminated for early pregnancy detection, pregnancy was confirmed on Days 18th and 22nd by RMPT and serum P4 analysis 42(58.4%) and 37(51.4%) respectively, and on Day 28th Ultrasonography 32 (44.5%) post AI. Although pregnancy detection with RMPT was statistically non significant but the values was higher between the tests. RMPT was the most sensitive (88.9%) but less specific (72.2%) taking Ultrasonography as a gold standard. Pregnancy later performed by transrectal palpation on Day 40 post AI showed 27 (37%) indicating the presence of corpus luteum and early embryonic mortality. RMPT was found to be relatively cheaper, and easier to apply under field condition. Results comparable to ultrasonography can be found if the test is repeated 7-8 days later. In conclusion, semen extenders can be locally prepared to mitigate the cost commercial extenders with even better conception results. Diagnosis of pregnancy can also be made at an earlier stage using a RMPT under the field conditions of Ethiopia.
EFFECT OF BREED, PARITY AND BODY CONDITION ON FFICACY OF DOUBLE AND SINGLE PGF2α BOVINE ESTRUS SYNCHRONIZATION PROTOCOL IN BORAN AND CROSSBREED DAIRY CATTLE IN BISHOFTU, ETHIOPIA
(2018-06) EJIGAYEHU, DEMISSE; Dr. Alemayehu Lemma, Dr. Tamrat Degefa
From January 2017 to June 2018 study was conducted to evaluate efficacy of single and double bovine estrus synchronization in boran and cross breed dairy cattle in Bishoftu, Ethiopia. Estrus Synchronization is one of the reproductive management tools. Failure to detect estrus in timely and accurate manner is a major factor limiting reproductive efficiency. For this different factors may suggested. The current study was conducted with the hypothesis of, breed, parity; body condition score can influence estrus synchronization with the objectives of evaluating estrus response rate of double and single PGF2α, studying estrus characteristics and effect of breed, parity and body condition on the outcomes of single and double PGF2α. Randomized block design were employed, a total of 54 animals’ heifers and cows of local and cross breed were selected, and 36 for double and 18 single PGF2α. Animals were grouped based on treatment, parity, body condition and breed. Insemination was done based on standing to be mounted signs of estrus and pregnancies were diagnosed after 21 days post insemination using ultrasonography. Results of the study showed that an overall estrus response of 72.2% and conception rate were 30%. Body condition of cows/heifers significantly (p<0.05) effect on estrus response, treatment protocol and parity also influence interval to estrus. Estrus characteristics such as restlessness (57.4%), standing to be mounted (53.7%) and mounting others (51.9%) were the most frequent observed signs, were standing o be mounted significantly influence(p<0.05) ovulation.On conclusion; estrus response was influenced by body condition, but treatment protocol, parity and breed had no effect. Interval to estrus was influenced by parity and treatment protocol. On the other hand estrus characteristics like standing to be mounted had influence on ovulation rate. 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OVARIAN FOLLICULAR DYNAMICS AND EFFECT OF BREED ON CONCEPTION RATE TO ARTIFICIAL INSEMINATION WITH FROZEN SEMEN IN MARES
(2018-06) Ararsa, Duguma; Dr. Alemayehu Lemma
Equine reproduction is unique by having long behavioral estrus and variations in ovarial follicular dynamics. Additionally, differences in time of breeding between breeds and individuals of mares made difficulty to standardize breeding time. There were a limitted data on equine reproduction and breeding in Ethiopia. An experimental study was conducted at Balderas sport horses and recreational center, Addis Ababa, Ethiopia from January to June, 2018 to determine ovarian follicular dynamics and evaluate conception rate to frozen semen in local and exotic cross breed mares. A daily transrectal ultrasonography was carried out to evaluate uterine changes and ovarian structures for 2-3 consecutive estrus cycles. Inseminations were done post ovulation within an average of 6-9h using frozen thawed semen. The mean (+SEM) of cross sectional uterine diameter were 44.4+0.5mm and 45+0.5mm for local and cross breed mares respectively; whereas endometrial fold development indicated 3.1+0.1 in local and 2.8+0.1 scores in cross breed mares with significant difference at P<0.05. The mean (+SEM) of preovulatory follicle diameter in local and cross breed mares indicated 49.1+1.0mm and 50.1+0.8mm respectively. Fast growth of dominant follicles in cross breed shorten interovulatory interval than local breed mares with length of estrus, 7.0+0.9 days for local and 6.1+0.6 days for cross breed mares. A positive correlation of teasing scores, uterine diameter and endometrial fold scores with diameter of developing dominant follicles in the present study has been used to estimate time of eminent ovulation. The overall conception rate to frozen semen was 15/21 (71.43%) with 8/11 (72.73%) in cross breed and 7/10 (70%) local breed mares. Conception rate increased significantly with increased number of services/conception with an overall mean +(SEM) of 2.2+0.2 services/conception. More number of services/conception were required for local breed (2.7+0.2) than cross breed mares (1.8+0.3) and again for lower body condition scores than higher condition scores of mares. In conclusion, measuring a cross sectional uterine diameter, endometrial folding scores and teasing scores with developing dominant follicles and their correlation were good parameters to determine relative time of ovulation and breeding in mares; whereas good management of mares for improved body conditions could require to decrease number of services per conception.

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