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Item Improving the performance of Mpwapwa breed cows in Tanzania : a fertility management approach : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Science at Massey University, School of Veterinary Science, Manawatu(Massey University, 2024-12-12) Kabuni, Kabuni ThomasBeef cattle farming is an important part of Tanzania’s economy being widespread throughout Tanzania. It is commonly practiced by small-scale farmers, often in conjunction with other agricultural and commercial activities. As part of the colonial government’s efforts to develop agriculture in Tanzania in the 1940’s, the Mpwapwa breed was developed, largely from Bos indicus stock, as a dual-purpose breed to provide better beef and milk production. The Mpwapwa TALIRI research centre, in the Dodoma region of Tanzania, maintains a nucleus herd of Mpwapwa cattle from which it has provided breeding stock and, prior to 1973, an artificial insemination (AI) program to farmers. These programs fell into abeyance during the post-colonial era. Critically, the AI service was discontinued until TALIRI Mpwapwa started to re-equip its facilities in 2018. The major limiter to re-establishing the AI service has been the high cost and poor availability of liquid nitrogen, which means that it is not feasible to develop a service that is dependent on cryopreserved semen. In the past globally, and in New Zealand currently, bovine AI services have been based upon chilled or ambient temperature (AT) diluents, so the feasibility of developing a new AI service for Mpwapwa cattle using ambient-temperature semen was investigated. Most of the use of AT diluents has been in temperate climates, so an important component of re-establishing the AI service was to determine whether AT diluents could sustain sperm viability at the high (>30oC) temperatures that pertain in Tanzania. The first step was to survey farmers who kept Mpwapwa cattle about their management and breeding practices using a cross-sectional survey. This was undertaken to determine whether they were interested in an AI program for their cattle and whether they thought it would be a useful method of breeding for their cattle. A survey was administered across 100 farmers in the Mpwapwa region. Median herd size was 7 (range 1-150) and median farm size was 12 acres (0.4-500), milk yields were generally under 5 L/cow/day and carcass weights were typically 112-142 kg. The Mpwapwa breed was regarded as better than other local breeds. Only 17 farmers had used AI, almost always after single-PGF2α synchronisation. However, 69 farmers who had not used AI were interested in doing so and 61 considered that AI was better than natural bull mating being aware of the significant of AI on livestock breeding. The conclusions from the survey were that an AI service would have to be tailored around small herds, probably with fixed-time AI (FTAI) after single-PGF2α synchronisation, and would have to offer farmers significant improvements in animal genetics and fertility and/or easier management of breeding than at the present. As the Mpwapwa bulls had never been evaluated to determine whether their semen was of adequate quality to use in an AI service, the next step was to undertake breeding soundness examination (BSE) of the bulls in the TALIRI Mpwapwa stud. The 53 heaviest bulls out of the total stud of 120 were subjected to a full BSE including semen examination (collection by electroejaculation). Scrotal circumference was similar in bulls that were 24-36 months old (mean: 27.1 cm, SD: 1.6 cm) and those that were >36 months old (mean: 27.8 cm, SD: 2.0 cm). Semen was successfully collected from 44 bulls. Mean ejaculate volume was 5.5 mL (SD: 2.7 mL). Only 4 bulls did not have ≥75% morphologically normal sperm. Mean ejaculate density was relatively low at 303 x106 sperm/mL (range: 57-966, SD: 258 x106 sperm/mL). Density was >400 x106/mL in 31 bulls, >700 x106/mL in 2 bulls and >800 x106/mL in 6 bulls. These 8 bulls were considered suitable for use in an AI program. The variation of semen quality was largely as expected for a breed that had not been subjected to any form of selection for breeding ability. Findings for these Mpwapwa breed bulls largely align with those of similar low body-weight breeds of B. indicus that are found in East Africa and South-East Asia, but are significantly less than would be expected from the improved indicus breeds of South America, Australia and southern Africa. DNA fragmentation was examined in the same 53 bulls, again, as the status of these hitherto unselected bulls was unknown. Most bulls had unfragmented sperm (mean: 94.7%, SD: 6.8, Mode: 100%), with only 5 bulls having <90% normal sperm. Fragmentation was therefore not sufficiently widespread in the bull stud to cause concern about their use in AI. The next step was to assess the survival of sperm at ambient temperatures. Ejaculates from 35 bulls were diluted 1:1 in Tris-egg yolk (TE), Optixcell and coconut water, loaded into 0.25 mL mini- straws and incubated in water baths at 20°C, 27°C and 33°C (Year 1) or 8°C, 17°C and 33°C (Year-2). Motility was evaluated using computer-assisted analysis after 6, 24, 48, 72 and 120 h. Sperm survival was related to temperature, such that survival at 8°C was better than at other temperatures. Survival in coconut water was poor, with limited survival even at 24 h. Mean survival at 72 h was <40% in both TE and Optixcell, but was >40% at 48 h except at 32oC. These results suggested that storage at <20oC for up to 48 h would give acceptable motility (i.e. ≥50%) for use in AI. Sperm from some (n=4) individual bulls survived, however, for up to 120 h at 8oC and from 2 bulls at 17oC. Semen from 3 bulls survived for 120 h at 32oC. These results showed that storage for 48 h at 17°C in TE or Optixcell was feasible for most bulls, and individuals could be identified whose semen survived longer and/or at higher temperatures for at least 72 h. Thus, maintaining semen at ambient temperatures of 32°C was difficult for >24 h, but was readily achievable in an AT diluent with a modest amount of cooling for 48 h. This survival would permit an AI service based on AT semen, provided inseminations could be performed soon after collection, or after a period of modest refrigeration. Finally, a proof-of-concept AI trial was undertaken, in which 303 cows were inseminated with cryopreserved or AT semen after a double-PGF2α synchronisation (to detected oestrus after PGF2α- 1 and by FTAI after PGF2α-2). Conception rates to AI were 62% to AT and 38% to cryopreserved semen (final pregnancy rates were 99% and 97% respectively after 12 weeks of bull mating). Whilst the trial was not undertaken to demonstrate that one method was superior to the other, it did demonstrate that FTAI with AT semen was at least as good as with cryopreserved semen. In terms of developing an AT AI service, this thesis has shown that it would likely be well-received by smallholder farmers, that there is a cohort of bulls which are of satisfactory breeding quality for use in AI, that their semen survives for long enough for AT semen to be the basis of an AI service, and that results to FTAI are at least as good as with cryopreserved semen. In summary, the protocol itself is cost-effective and, as such, it could be used within the Tanzanian beef cattle breeding programmes. Being simple to schedule should make it easily accessible and implementable by poor smallholder farmers in the Mpwapwa region and, hence more accessible than other expensive protocols with more hormones. Even compared to natural mating, the costs of AT AI are still cheaper, making it more affordable than the costs of buying and managing a high genetic merit Mpwapwa bull. Wider screening of bulls for those whose semen survives longer and/or at higher ambient temperatures would allow for the selection of bulls with the highest quality semen. Addition of a limited degree of refrigeration (maintaining semen at 15-20oC) would allow more flexibility to the AI collection/processing centre.Item Comparative study between fixed-time artificial insemination and natural mating on reproductive performance (conception and pregnancy rates) of Mpwapwa breed cows in Tanzania : a thesis presented in partial fulfillment of the requirement for the degree of Master of Science in Animal Science, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand(Massey University, 2017) Kabuni, Kabuni ThomasThe aim of this project was to assess whether using a PGF2α synchronization protocol in Mpwapwa cattle would improve reproductive performance. A standard 14-day PGF2α synchronization protocol with a single FTAI was compared to NM over a 12-weeks breeding season. At the end of the study, 39/100 cows were pregnant in the FTAI group and 49/100 cows were pregnant in the NM group. This difference was not statistically significant (P=0.21), although the odds ratio of pregnancy was lower in the FTAI group than the NM group (unadjusted RR=0.8; 95% - CI 0.58-1.09). However, cattle in the PGF2α-treated group were only inseminated once, whereas the NM group could be naturally mated on multiple occasions during the breeding season; In addition, the use of PGF2α allowed the use of AI, which is not feasible under most Tanzanian systems when cattle come into oestrus naturally. Thus, the results of this study suggest that PGF2α -based synchronization and FTAI, particularly if used alongside natural mating, can improve the reproductive performance of Mpwapwa breed cattle as well as allowing for greater genetic gain than occurs with naturally mated cattle. The proportion of cows that came into heat and displayed behavioural signs after administration of the first PGF2α injection was very low (only 10/100 cattle). The reason for this poor response is unclear. It could be that oestrus detection was not very effective, or that a higher than expected proportion of cattle did not have a responsive CL. The most likely cause of the latter is a higher proportion of cattle in anoestrus. Further investigation of the reproductive state of Mpwapwa cattle at the start of the breeding season would identify how important anoestrus is as a cause of poor reproductive performance. If anoestrus is common, identifying cattle in anoestrus at the start of the season could be useful, as they could be treated using progesterone-based programmes and cattle with a CL could be treated with PGF2α. Key words: Mpwapwa breed cattle, PGF2α synchronization protocol, FTAI, NM, Reproductive performance.Item A study of the transport of spermatozoa in the reproductive tract of the ewe after artificial insemination : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science at Massey University(Massey University, 1975) Giles, Kerin HarleTwo preliminary experiments were conducted with artificially inseminated ewes to examine the considerable variation in counts of spermatozoa recovered in flushings from the reproductive tract. In the second trial, road transport stress immediately after insemination caused a reduction in the number of spermatozoa reaching the Fallopian tubes. In the third trial, sperm transport after insemination with fresh, undiluted semen at two sites in the tract at predetermined times relative to synchronised ovulation (progestagen-HCG treatment) was investigated. Deposition of semen at the uterine end of the cervix or within the uterus using a specially adapted inseminating pippette, resulted in the recovery of higher numbers of spermatozoa from the uterus and Fallopian tubes 4 hours after insemination, than did insemination at the external cervical os. Twenty-four hours after insemination similar numbers of spermatozoa were found in all segments for both sites of insemination. Deposition of semen before or after the expected time of ovulation, or at both times, had little effect on the numbers of spermatozoa recovered. More ova with accessory spermatozoa were recovered from oviducts containing high numbers of sperm. The transport of spermatozoa after deposition of fresh or frozen semen into the uterus by surgical and non-surgical methods, was studied in a fourth experiment. The number of spermatozoa recovered from the uterus and isthmus was similar for both types of semen, but only 'fresh' spermatozoa deposited at surgery, reached the ampulla in significant numbers. 'Frozen' sperm deposited by both methods, and fresh sperm deposited non-surgically, did not reach the ampulla within 4 hours of insemination. Impaired transport of 'frozen' spermatozoa to the site of fertilization appeared to be a result of reduced longevity of these cells within the female tract, and nay involve factors such as breakage of spermatozoa in the uterus, and delayed transport in the oviducts. The improvement of sperm transport in the ewe through the development of non-surgical, intrauterine inseminations and using either freshly extended or frozen semen, are discussed.Item A semi-stochastic simulation model of the New Zealand dairy cattle artificial insemination industry : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science at Massey University(Massey University, 1993) Knutson, Russell EdwardA univariate semi-stochastic simulation model was written with the objective of economically evaluating a range of breeding programmes from the perspective of a privately owned artificial insemination company. To test the validity of the model four breeding programmes were evaluated. Three of the options were variants of the first which considered the progeny testing of 35 young sires sourced from the New Zealand and United States registered populations. Modifications to the initial programme centred around increasing the number of young sires sampled and the use of the New Zealand recorded, but unregistered, cow population as a source of bull dams. Stochastic simulation was used for the male sub-populations of sires-to-breed-sires and sires-to-breed-dams, simulating each animal individually by drawing them from a univariate normal distribution. Cow populations, because of size, were simulated deterministically using expectations based on existing dairy industry structure. Selection was imposed on the population for a single production trait with a heritability of 0.25. Selection intensities and generation intervals depended on user defined inputs such as which populations were available for selection, how many sires of sons were to be used, and how many young sires were to be sampled. The genetic simulation was replicated ten times for each of the four options, covering a twenty year time frame. Economic analysis was undertaken by modelling two companies. One company maintained a stable breeding programme throughout the simulation so that the changing fortunes of the other could be measured as its breeding programme altered. Gross profit was estimated from semen sales and the costs associated with each programme subtracted. The resulting pre-tax profit was adjusted for tax and discounted to a net present value. The effect of planning horizon on profitability was examined by extracting data at five year intervals, coefficients of variation were used to analyse risk and all options were contrasted with the base in percentage terms to overcome the need to account for fixed capital costs, which were assumed to remain constant across breeding programs. For the programmes modelled it was found that cost structure played a bigger part in determining net profit than rate of genetic gain. Secondly, expanding the base population in which selection was carried out was more important than increasing the number of young sires sampled.Item Transcervical artificial insemination of Romney ewes : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science in Animal Science at Massey University(Massey University, 1996) Poff, Gerard JohnTranscervical AI was attempted in 178 mixed age Romney ewes. AI was performed between 48 and 52 h after synchronisation of oestrus with progesterone impregnated CIDRs. Fresh or frozen-thawed semen was used and each insemination dose contained approximately 100 million spermatozoa. Half of these ewes were treated prior to AI with clenbuterol hydrochloride (PanipartTM) in an attempt to cause cervical softening to allow insertion of an inseminating pipette through the cervix. Reproductive tracts were recovered from 32 ewes in which transcervical insemination was achieved. After flushing each tract the spermatozoa were counted from the cervix and from the left uterine segment. 94% of ewes showed oestrus within 48 h of CIDR withdrawal. Variation in time of onset of oestrus prior to AI did not affect conception rate (P>0.05). The conception rate based on non-return to oestrus was 34%. A greater percentage of ewes conceived to insemination with fresh semen (42%) than that for frozen-thawed (24%) (P<0.05). Clenbuterol did not affect depth of cervical penetration but it did reduce bleeding at the cervical os observed at AI (P<0.01). Parity/age of ewe significantly affected depth of cervical penetration (P<0.001) and the time taken to inseminate (P<0.01), with few two tooth ewes successfully transcervically inseminated (76% were vaginally inseminated). Sperm numbers were significantly higher in the cervices of ewes that were inseminated with fresh rather than frozen-thawed semen (P<0.05). Numbers of spermatozoa recovered were low in comparison to similar studies and were related to the extent of cervical damage (recorded at dissection of reproductive tracts). Uterine sperm counts were significantly lower (P<0.05) for those ewes where cervical damage was observed. The depth of insemination was estimated at the time of AI, and full cervical penetration was recorded in 68% of the mature ewes. However examination of the ewe cervices at dissection suggested that this figure was misleading. Anatomical evidence suggested that the inseminating needle had frequently lodged in the cervical wall and successful passage had not been achieved. Therefore it was likely that semen was deposited frequently in areas of damaged cervical tissue which would have been detrimental to survival of spermatozoa. This was probably the main reason for the low sperm numbers in the reproductive tracts and consequently the low conception rate. For those ewes where full cervical penetration was recorded at AI, only 28% conceived.Item Some aspects of artificial insemination in the bitch, using frozen semen : a thesis presented in partial fulfilment of the requirements for the degree of Master of Veterinary Science at Massey University(Massey University, 1992) Wilson, Marion ScobbieThe development of freezing techniques for dog semen allowing long term storage of semen from valuable stud dogs and its use locally or thousands of miles away has opened up exciting new prospects for dog breeding. However, it has not been possible to consistently achieve acceptable pregnancy rates and litter sizes with frozen semen. The reason for this arises from the many factors involved in processing and inseminating frozen canine semen and their complex inter-relationships. In order to successfully use semen prepared in this way it is essential to understand the effect processing has on the fertilising capacity of sperm and the implications this may have regarding the techniques required for semen insemination. The key problems revolve around establishing the period for which such semen remains able to fertilise ova, being able to identify when ovulation takes place so that timing of insemination occurs when ova are ready for fertilisation, and having a technology that will allow placement of the semen in a position from which fertilisation is likely to be achieved. In this study 18 bitches were divided into three groups on a random basis. Group 1 bitches were inseminated twice with four straws of semen (a total insemination dose of 240 to 280 x 106 live sperm), the semen being deposited into the uterus using the 'Norwegian' insemination technique. Group 2 bitches received the same insemination dose deposited into the uterus using the 'Endoscopic' technique (a technique developed for this trial), and Group 3 bitches received 25% of the semen dose in Group 1 and 2 (a total insemination dose of 60 to 70 x 106 live sperm), inseminated using the 'Endoscopic' technique. The semen all came from one stud dog. Insemination timing was based on blood progesterone concentration determined using a commercial ELISA kit. The results from the kit were compared with RIA determinations of plasma progesterone to validate its accuracy. Visual observations of the bitch, vaginal cytology and vaginal endoscopy observations were also considered in relation to the timing of insemination. The pregnancy rate over all three groups was 83.3% with a mean litter size of 7.5 (range 4 - 11) pups. There was no difference in pregnancy rate or litter size between the groups. The insemination protocol adopted in respect of semen dose, insemination timing and site of deposition of semen demonstrated that it was possible to achieve good pregnancy rates and litter sizes following the insemination of frozen semen. The new 'Endoscopic' method of depositing the semen into the uterus was shown to provide an effective alternative method to the 'Norwegian' technique. The results of insemination with a significantly lower sperm dose of frozen semen demonstrates that equivalent pregnancy rates and litter sizes to those achieved with high doses of semen, can be achieved when the semen used is of high quality. It was also shown that using blood progesterone concentration as the basis for timing insemination provides an alternative and perhaps more appropriate method of ensuring insemination occurs at the optimum time than traditional methods used; the progesterone kits were found to be reliable in this trial and were particularly useful because they were simple and provided results within hours.Item Studies on the in vivo cleavage and the in vitro culture of New Zealand romney sheep ova : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science at Massey University(Massey University, 1967) Tervit, Harry RobinThe purpose of this present study was to observe the cleavage of fertilised Romney ewe ova in vivo and to compare this with cleavage of ova cultured in vitro. A method of long term in vitro culture of ova was developed and the technique of ovum transplantation used to test ovum viability.Item The use of oestrous cows for the pre-collection preparation of mature bulls standing at an artificial breeding centre : a thesis presented to the Victoria University of Wellington in partial fulfilment of the requirements of the degree of Master of Agricultural Science(Massey University, 1962) Macmillan, K. L.Since 1949, a marked expansion in the commercial operation of artificial breeding has taken place in New Zealand. This expansion represents an increase from 1,400 inseminated cows in 1949, to 556,000 inseminated cows in 1961. (New Zealand Dairy Prod, and Marketing Board Ann, Rept. (1962)). The principle objective of the Artificial Breeding Service is to offer farmers the use of top sires from each of the main dairy breeds in New Zealand. These sires are selected on the basis of progeny test records. The rating which each proven sire receives is calculated from the butterfat production records of a sire's daughters. The butterfat records of each daughter are corrected for are differences and compared with the age-corrected average production of the herd-mates. Bulls selected for use as A.B. sires are placed at one of the two Artificial Breeding Centres which provide a Dominion-wide coverage. Because of the seasonal nature of daily farming in New Zealand, the bulk of the demand for semen occurs during the spring mating period, and since chilled semen is the principle form of service offered, the bulls experience a peak working period of eight to twelve weeks at this tise of the year. Ths objective in development at the Centres has been to obtain maximum coverage from top sires compatible with satisfactory conception rates. In 1961, the 49-day non-return rate to first inseminations with chilled semen was 63/3% (New Zealand Dairy Production and Marketing Board Ann. Rept. (1962)).Item Artificial breeding of the domestic fowl : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science in Animal Science at Massey Universit(Massey University, 1967) Rumball, WalterArtificial breeding is an interception of natural mating procedure, by the collection of semen and its retention in vitro before deposition in the female genital tract. Semen is usually collected after an induced ejaculation into a suitable receptacle, from the engorged copulatory organ situated in the cloaca of the male fowl. When removed from their first natural environment in the male genital tract and retained in vitro, precautions are needed to preserve spermatozoa function. This is the most artificial phase and the one to which most research has been directed in an attempt to extend semen storage time. Insemination is the final phase of semen transfer and the techniques for depositing semen in the female genital tract, parallel those used for other species. A study of artificial breeding in the domestic fowl is presented in this thesis.Item A study of transcervical artificial insemination in sheep(Massey University, 1995) Usboko, YohanesThe study describes two trials on artificial insemination in Romney ewes. Trial 1 was conducted to examine the anatomical site in the reproductive tract of the inseminating needle after transcervical insemination, and to evaluate the effect of the needle in causing cervical tissue damage based on the microscopic assessment of cervical slides. Trial 2 was undertaken to compare the effect of intrauterine, cervical or transcervical methods of insemination with fresh semen on fertility. Two hundred and five mixed-aged ewes (3-8 years old) were hormonally treated with CIDR-G for 12 days and these were removed after this period. Forty-eight hours later, to monitor the onset of oestrus, they were joined with 10 harnessed vasectomised rams. Oestrous detection was undertaken twice daily, at 1.00 am and 1.00 pm. Most ewes were synchronised in oestrus over 2 days after CIDR withdrawal but there was an extended period of 'second' oestrus when the inseminations were conducted. In Trial 1, transcervical insemination with Indian ink was performed in 29 ewes at the second oestrus, and then they were euthanased with Sodium Pentobarbitone. Position of the inseminating needle in situ was determined at dissection. The genital tract was removed and the uterus opened to determine whether Indian ink had penetrated. The cervix was then split into three similar sized portions, fixed in Bouins solution, and sections histologically processed and stained for slides. The slides were microscopically examined by two evaluators to determine damage scores. In trial 2, semen samples (concentration at least 3 x 109 spermatozoa ml-1, motility minimal 4) were collected per artificial vagina from 5 Romney rams, pooled and freshly diluted with UHT-milk to 8 x 108 spermatozoa ml-1. One hundred and seventy-five cyclic ewes were randomly assigned to either of three AI techniques (intrauterine, cervical and transcervical), and were inseminated with freshly diluted semen at a mean interval of 6.1 0.26 h after second oestrus was detected. In slaughtered ewes, penetration of the modified needle through the lumen of the cervix and even into the uterus occurred more that with the unmodified needle (90% vs 68%; 0.05