No description available.

This work was carried out to compare the endocrine function of ovarian tissue isolated in vitro, in an identical environment between ewes and ewe lambs. Furthermore, to determine whether the differences in endocrine and reproductive function of ewes and ewe lambs are related to differences in the proteomics of corpora lutea, follicles and oocytes. Oestradiol concentrations in tissue cultured in TCM-199 were similar for ewe and ewe lamb follicles collected post slaughter on day 9 to 12 of the oestrous cycle and cultured for different incubation times but increased with increase in follicular size. Oestradiol secretion was greater (P<0.001) for ewe and ewe lamb follicles cultured in media with FCS. Media progesterone concentrations were higher (P<0.001) for ewe than ewe lamb follicles. Progesterone in media and in follicular fluid was increased with increased follicles size. Ewe CL, collected on day 9 to 12 of the oestrous cycle, produced more progesterone than ewe lamb CL when cultured in TCM-199 with or without FCS, PVA, BSA. Proteomics indicated more large spots, in ewe follicular and CL tissue average gels compared with ewe lamb average gels. The protein spots were estimated to be between 45 to 97 kD, in both tissue and age groups, this range of molecular weight could have affected steroid hormone synthesis. (Chapter.3). Ewe and ewe lamb follicles cultured with FSH and LH produced more oestradiol than without, furthermore, oestradiol concentration increased with follicle size. There was no difference in media oestradiol concentration between age groups after 24 h of culture. However, for follicles cultured for 2, 4 or 6 h, concentrations were greater after 4 and 6 h, in ewes than in ewe lambs. Overall ewe lamb follicles produced more progesterone (P<0.001) than ewe follicles when cultured with FSH and LH when cultured for 24 h, but no difference was observed after 2, 4 and 6 hours between ewes and ewe lambs Overall ewe follicles produced more (P<0.002) progesterone than ewe lambs when cultured with different concentration of hCG although there was no difference between ages with respect to oestradiol concentrations. Ewe CL secreted more progesterone (P<0.002) than ewe lamb CL, when cultured for 0 or 24 h. Furthermore, tissue concentrations were greater in ewe CL than ewe lamb CL after incubation in TCM-199, TCM-199 plus BSA, TCM-199 plus FCS and TCM-199 plus PVA. Ewe lamb CL produced more progesterone than ewe CL in medium containing LH when cultured for 2, 4 and 6 hours, but ewes produced more progesterone than lambs when CL were cultured with different concentrations of hCG. Relative to untreated shells, the protein profiles of the ewe follicular shells treated with FSH and LH changed to a greater extent than that of the ewe lambs treated gels in both ages contained more protein spots than control gels. The largest spots were estimated to be between 30 and 97 kDa (Chapter.4). There was no difference between age groups for follicles from ewes and ewe lambs treated with ovagen in oestradiol and progesterone concentrations observed after 2,4, 6 and 8 h of incubation in TCM-199. However, treatment with ovagen plus hCG resulted in higher oestradiol and progesterone concentrations in the media from ewe follicles compared to ewe lambs. Furthermore, there were more protein spots in the range 30 to 66 kDa marker in gels from ewes treated with either ovagen or ovagen plus hCG than for ewe lambs (Chapter 5). Lamb oocytes were smaller than ewe oocytes and developed to a lesser extent in culture. Furthermore, the addition of FCS to TCM-199 caused greater cytoplasmic and nuclear maturation than other media used in this experiment and ewe lamb oocytes have a similar 1D protein bands compared with ewe oocytes, but contained less protein (Chapter 6).

No description available.

No description available.

No description available.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 5 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 4 uppsatser.

Uterine defences against bacterial challenge are more efficient during oestrus than during dioestrus. The exact reasons and mechanisms responsible for this difference are, however, still incompletely understood. The leukocyte reaction is one of the defence mechanisms that has been cited as being able to respond better to a bacterial challenge during oestrus than during dioestrus. The aim of the present study was to test the hypothesis that the magnitude of endometrial leukocyte migration following the instillation of semen into the uterine lumen is greater during oestrus than during dioestrus. Eight Nooitgedacht mares of normal fertility, aged between 8 and 16 years (11.5 ± 2.7; mean ± SD), were used in the study. Each mare received a different treatment during each of four oestrous cycles, with a rest cycle after each treatment. Two treatments were performed during dioestrus and two during oestrus. One treatment for each stage of the cycle was a control treatment without challenge to the endometrium. At time zero of challenged cycles a single aliquot of 13 ml raw semen, frozen-thawed without addition of any cryoprotectant or extender, was instilled into the uterus. An endometrial biopsy was taken 6 and 48 h after time zero and a swab for cytology and culture (if cytology was positive) was collected 48 and 120 h after time zero. An image analyzer was used to record the total number of cells, round cells, neutrophils and eosinophils per unit surface area of epithelium, stratum compactum (SC) and stratum spongiosum (SS). The relative number of round cells, neutrophils and eosinophils were expressed as proportions of the number of each cell type to the total number of cells. The use of an image analyser made the collection of quantitative data from histologic sections possible. However, the operator still had to make some critical decisions, namely to choose the field of the section for analysis and to assign individual cells to a chosen category. The total numbers of cells in the epithelium and the SS were greater during dioestrus than during oestrus, while no such difference could be demonstrated for the SC. The stage of the oestrous cycle had no meaningful influence on any other (measured or calculated) variable. During challenged cycles, absolute and relative numbers of neutrophils were significantly greater in the epithelium, SC and SS than during control cycles. There was an interaction (not always reaching significance) between treatment and time with regard to the absolute and relative numbers of neutrophils in epithelium and SS and round cells in the epithelium. Numbers of neutrophils and round cells were significantly higher 6 h after treatment than 48 h after treatment in challenged cycles, but did not differ during control cycles. During challenged cycles, the stage of the oestrous cycle when treatment occurred had no effect on the duration of the induced endometritis, the occurrence of positive cytology or culture results, or the type of bacteria that were cultured. Regardless of the stage of their cycles when they were challenged, all mares rid themselves of the opportunistic pathogens placed into the uterine lumen within one oestrous cycle. The hypothesis was rejected and it is therefore concluded that the stage of the oestrous cycle did not influence the magnitude of the endometrial leukocyte response to a standardized challenge with semen in these reproductively sound mares. A similar study will be required to test whether this conclusion also holds true for mares that are susceptible to endometritis. / Dissertation (MMedVet (Gyn))--University of Pretoria, 2006. / Production Animal Studies / unrestricted

Durante o início da primavera, na região oeste do Estado de São Paulo, fêmeas Suffolk (n=91) foram tratadas com 1 (1M) ou 2 implantes (2M) subcutâneos de 18 mg de melatonina (Mélovine), acompanhadas por um lote controle (C), e submetidas ao efeito macho por rufiões, 42 dias após a colocação do implante. Após nove dias, os rufiões foram substituídos pelo reprodutor, tratado com 01 implante, com o qual as fêmeas permaneceram durante 51 dias, em sistema de monta a campo. O diagnóstico de gestação foi efetuado por ultra-sonografia e apresentou 36,7%, 43,3% e 38,7% de animais gestantes no primeiro exame, e ao segundo, 36,7%, 46,7 e 48,4% para os grupos 1M, 2M e C, respectivamente. Não houve diferença significativa entre o intervalo efeito macho/cios férteis (20,8 &plusmn; 10,26; 25,0 &plusmn; 12,75 e 27,0 &plusmn; 9,68 dias), encarneiramento/acasalamentos férteis (11,8 &plusmn; 10,26; 16,0 &plusmn; 12,75 e 18,0 &plusmn; 9,68 dias), taxa de fertilidade (43,3%; 53,3%; 51,6%), taxa de parição (36,7%; 53,3% e 48,4%), prolificidade (1,36; 1,50 e 1,27) entre os grupos 1M, 2M e C, respectivamente. A ocorrência de um efeito de facilitação social, provavelmente permitiu que fêmeas não tratadas (C) voltassem a ciclar. O tratamento com melatonina foi capaz de adiantar a estação reprodutiva, permitindo acasalamentos de primavera/verão e proporcionando parições de outono/inverno. / Ninety one Suffolk ewes were randomly allotted to none (control group), single (group 1M) or two (group 2M) melatonin slow releasing subcutaneous implants (18 mg, Mélovine) during spring season in the west region of São Paulo. Fourty two days after the implantation ewes were submitted to ram effect trough vasectomized teasers exposition and substituted by a ram treated with one melatonin implant following 51 days of mating period. Pregnancy diagnosis was performed by real-time ultrasound showing 38.7, 36.7 and 43.3% of pregnancy for groups C, 1M and 2M at the first examination, and 48.4, 36.7 and 46.7% of pregnancy respectively at the second examination. It was observed no significant difference between ram effect / fertile oestrus (27.0 &plusmn; 9.68, 20.8 &plusmn; 10.26, 25.0 &plusmn; 12.75 days), mating / pregnancy (18.0 &plusmn; 9.68, 11.8 &plusmn; 10.26, 16.0 &plusmn; 12.75 days), fertility rate (51.6%, 43.3%, 53.3%), parturition (48.4%, 36.7%, 53.3%), prolificity (1.27, 1.36, 1.50) for groups C, 1M and 2M respectively. The occurrence of social facilitation effect robably permitted the untreated group (control group) returned to cycle. Melatonin treatment advanced the reproductive season permitting spring / summer mating and autumn / winter parturitions.

Durante o início da primavera, na região oeste do Estado de São Paulo, fêmeas Suffolk (n=91) foram tratadas com 1 (1M) ou 2 implantes (2M) subcutâneos de 18 mg de melatonina (Mélovine), acompanhadas por um lote controle (C), e submetidas ao efeito macho por rufiões, 42 dias após a colocação do implante. Após nove dias, os rufiões foram substituídos pelo reprodutor, tratado com 01 implante, com o qual as fêmeas permaneceram durante 51 dias, em sistema de monta a campo. O diagnóstico de gestação foi efetuado por ultra-sonografia e apresentou 36,7%, 43,3% e 38,7% de animais gestantes no primeiro exame, e ao segundo, 36,7%, 46,7 e 48,4% para os grupos 1M, 2M e C, respectivamente. Não houve diferença significativa entre o intervalo efeito macho/cios férteis (20,8 &plusmn; 10,26; 25,0 &plusmn; 12,75 e 27,0 &plusmn; 9,68 dias), encarneiramento/acasalamentos férteis (11,8 &plusmn; 10,26; 16,0 &plusmn; 12,75 e 18,0 &plusmn; 9,68 dias), taxa de fertilidade (43,3%; 53,3%; 51,6%), taxa de parição (36,7%; 53,3% e 48,4%), prolificidade (1,36; 1,50 e 1,27) entre os grupos 1M, 2M e C, respectivamente. A ocorrência de um efeito de facilitação social, provavelmente permitiu que fêmeas não tratadas (C) voltassem a ciclar. O tratamento com melatonina foi capaz de adiantar a estação reprodutiva, permitindo acasalamentos de primavera/verão e proporcionando parições de outono/inverno. / Ninety one Suffolk ewes were randomly allotted to none (control group), single (group 1M) or two (group 2M) melatonin slow releasing subcutaneous implants (18 mg, Mélovine) during spring season in the west region of São Paulo. Fourty two days after the implantation ewes were submitted to ram effect trough vasectomized teasers exposition and substituted by a ram treated with one melatonin implant following 51 days of mating period. Pregnancy diagnosis was performed by real-time ultrasound showing 38.7, 36.7 and 43.3% of pregnancy for groups C, 1M and 2M at the first examination, and 48.4, 36.7 and 46.7% of pregnancy respectively at the second examination. It was observed no significant difference between ram effect / fertile oestrus (27.0 &plusmn; 9.68, 20.8 &plusmn; 10.26, 25.0 &plusmn; 12.75 days), mating / pregnancy (18.0 &plusmn; 9.68, 11.8 &plusmn; 10.26, 16.0 &plusmn; 12.75 days), fertility rate (51.6%, 43.3%, 53.3%), parturition (48.4%, 36.7%, 53.3%), prolificity (1.27, 1.36, 1.50) for groups C, 1M and 2M respectively. The occurrence of social facilitation effect robably permitted the untreated group (control group) returned to cycle. Melatonin treatment advanced the reproductive season permitting spring / summer mating and autumn / winter parturitions.