Thesis (Ph. D.)--Carleton University, 1999. / Also available in electronic format on the Internet.

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Recombinant Bovine Somatotropin (rBST) is a biotechnology for increasing milk production in dairy cattle. The purpose of this research was to investigate and to build a better understanding of the complexities and controversies around this product in Canada. To accomplish this, I examined the Standing Senate Committee on Agriculture and Forestrys inquiry into rBST and the drug approval process. I compared and contrasted the testimony of witnesses and Senators and I uncovered emerging issues, patterns, and themes. This research was an exploratory and qualitative exercise that analyzed how the participants of this Senate inquiry conceptualized and contested the meaning of science, safety, and the states regulatory functions. <p> This research revealed several commonalities between Health Canada management, the human safety panel, and industry representatives. These witnesses argued that the drug approval process must be efficient, standard-driven, and based upon available scientific studies. These witnesses stated that they had confidence in the neutrality and competency of internal standard setting-agencies. They emphasized transparency rather than public participation in the drug approval process. Health and safety were conceptualized as static phenomena to be measured and evaluated by experts. <p>In contrast, Health Canada employees had several commonalities with the Senators, dairy representatives, and witnesses from citizen interest groups. Their testimony supports the argument that health and safety are dynamic social constructs. These actors transformed the boundaries of science to accommodate their precautionary framing of safety. They highlighted several problems with Canadas science-based regulatory framework and demanded that they have a decisive voice in the rBST decision. They challenged the hegemony of industrial capitalism by combining both scientific and lay knowledge to expose the limits and contradictions of industrialized agriculture.

Recombinant Bovine Somatotropin (rBST) is a biotechnology for increasing milk production in dairy cattle. The purpose of this research was to investigate and to build a better understanding of the complexities and controversies around this product in Canada. To accomplish this, I examined the Standing Senate Committee on Agriculture and Forestrys inquiry into rBST and the drug approval process. I compared and contrasted the testimony of witnesses and Senators and I uncovered emerging issues, patterns, and themes. This research was an exploratory and qualitative exercise that analyzed how the participants of this Senate inquiry conceptualized and contested the meaning of science, safety, and the states regulatory functions. <p> This research revealed several commonalities between Health Canada management, the human safety panel, and industry representatives. These witnesses argued that the drug approval process must be efficient, standard-driven, and based upon available scientific studies. These witnesses stated that they had confidence in the neutrality and competency of internal standard setting-agencies. They emphasized transparency rather than public participation in the drug approval process. Health and safety were conceptualized as static phenomena to be measured and evaluated by experts. <p>In contrast, Health Canada employees had several commonalities with the Senators, dairy representatives, and witnesses from citizen interest groups. Their testimony supports the argument that health and safety are dynamic social constructs. These actors transformed the boundaries of science to accommodate their precautionary framing of safety. They highlighted several problems with Canadas science-based regulatory framework and demanded that they have a decisive voice in the rBST decision. They challenged the hegemony of industrial capitalism by combining both scientific and lay knowledge to expose the limits and contradictions of industrialized agriculture.

The effects of insulin on milk production were tested employing two different approaches. Firstly, 12 Holstein cows were used to determine the effects of feeding calcium propionate (Ca prop) on dry matter intake (DMI) and production traits. The experimental design was a switchback with 2 treatments (Ca prop at 0 or 300 g/d). The DMI was lower when animals received Ca prop. Ca prop did not affect the yield of milk and its components; however, Ca prop increased protein content. The (acetate+butyrate)/propionate ratio in rumen fluid 2 h after feeding was lower when cows received Ca prop. Plasma insulin concentration was not different between treatments and the putative effect of propionate as an insulin secretagogue was probably related to the maintenance of insulin levels when DMI was lower. In conclusion, Ca prop is a potential feed ingredient to increase protein content in milk. The second approach consisted of intravenous infusion of insulin. A trial was designed to test the effects of insulin, recombinant bovine somatotropin (rbST) and their interaction in lactating dairy cows. Eight Holstein cows were used in a Latin Square design with 4 treatments: (1) intravenous infusion of saline, (2) infusion of saline and administration of 40 mg of rbST per day, (3) intravenous infusion of 12 mg of insulin per day coupled with glucose infusion and (4) rbST administration combined with insulin and glucose infusion. The theory that rbST causes a peripheral resistance to insulin was confirmed. Insulin infusion increased percent protein, percent casein and decreased milk urea content regardless of rbST administration. For milk yield, protein yield, casein yield, lactose percent and lactose yield, there was an interaction between insulin and rbST administration. Similarly, there was an interaction between insulin and rbST on plasma IGF-I levels. Fat yield was higher, with a higher content of long chain fatty acids, during rbST administration, regardless of insulin infusion. I

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Submitted by Mario BC (mario@bc.ufrpe.br) on 2017-05-04T13:28:46Z No. of bitstreams: 1 Luis Eduardo Pereira de Andrade Ferreira.pdf: 1304369 bytes, checksum: 620d432e3b7c65dcc3630bba676e1517 (MD5) / Made available in DSpace on 2017-05-04T13:28:46Z (GMT). No. of bitstreams: 1 Luis Eduardo Pereira de Andrade Ferreira.pdf: 1304369 bytes, checksum: 620d432e3b7c65dcc3630bba676e1517 (MD5) Previous issue date: 2014-08-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The efficiency of different biotechnologies applied to reproduction of the bovine female is closely related to the quality of ovulatory follicles. The recombinant bovine somatotropin (bST-r) has been described as stimulating follicle and oocyte. In this work we evaluated its influence on superovulatory response and embryo quality in Bos indicus cows, located at State of Pernambuco, Brazil.. Twenty cows, 10 in control group and 10 in treatment group (BST) were used. The animals in the BST group were treated with 500 mg of r-bST and controls with sterile saline solution every seven days totaling four applications until beginning of superovulation protocol (SOV). This began on a random day of estrous cycle considered D0, with the introduction of intravaginal Progesterone device (P4) combined with 2 mg of estradiol benzoate. At D4 it started follicular stimulation with 200mg of Follicle Stimulating Hormone in eight decreasing doses, with two daily applications. At D6 0.5 mg of cloprostenol was administered, with the P4 being removed in D7 and 24 hours after 1500 IU of Human Chorionic Gonadotropin was administered, and artificial insemination was performed 12 and 24 hours later. In D15 and 16 collections of embryos were carried out by non-surgical method, evaluated, classified and stored for later evaluation by fluorescence microscopy. All animals underwent monitoring of follicular dynamics in the days of treatment, collection and during the SOV protocol and collection of embryos; body condition score (BCS) was evaluated every seven days. The results were analyzed by ANOVA with a significance level of 5% . The BST group showed follicular diameter and number of follicles significante higher at some moments and it was seen a significant reduction of ECC (p<0.05). In other hand, only a numeric increase (p<0.05) was observed in the number of corpus luteum, total and viable embryos. It was observed a higher proportion of embryonic development stages more mature in BST group. So it was concluded that r-bST favors a strengthening of the SOV, however not targeting the ultimate goal, or a greater number of embryos, although numerically this occurred. Further study are necessary on application form and dosage used, based upon high variability of the results showed in other studies. / A eficiência das diferentes biotécnicas aplicadas à reprodução da fêmea bovina está intimamente relacionada à qualidade dos folículos ovulatórios. A somatotropina recombinante bovina (r-bST) tem sido descrita como estimuladora dos folículos e oócitos. Nesse trabalho avaliou-se sua influência na resposta superovulatória e na qualidade dos embriões de vacas Bos indicus, localizadas no agreste meridional de Pernambuco. Foram utilizadas 20 vacas, 10 no grupo controle e 10 no grupo tratamento (BST). Os animais do grupo BST foram medicados com 500 mg de r-bST e as controles com solução fisiológica estéril de sete em sete dias somando-se quatro aplicações até o inicio do protocolo de superovulação (SOV). Este se iniciou em dia aleatório do ciclo estral com a introdução do implante intravaginal de Progesterona (P4), associado a 2 mg de Benzoato de Estradiol, sendo considerado D0. No D4 se iniciou a estimulação folicular com 200 mg do Hormônio Folículo Estimulante, em oito doses decrescentes, com duas aplicações diárias. No D6 foi aplicado 0,5 mg de Cloprostenol, sendo a P4 retirado no D7 e 24 horas depois aplicado 1500 UI de Gonadotrofina Coriônica Humana, e inseminação feitas 12 e 24 horas depois. Nos D15 e 16 foram realizadas as coletas dos embriões, pelo método não cirúrgico, avaliados, classificados e armazenados para avaliação do total de células por fluorescência. Todos os animais passaram por acompanhamento da dinâmica folicular nos dias de tratamento, da coleta e durante o protocolo de SOV e coleta dos embriões, sendo avaliados de sete em sete dias o seu escore de condição corporal (ECC). Os resultados obtidos foram analisados por ANOVA com nível de significância de 5%. O grupo BST apresentou diâmetro folicular e número de folículos mais elevados em alguns momentos e redução do ECC (p<0,05), sendo observada elevação numérica (p>0,05) no número de corpos lúteos, embriões totais e viáveis, além de uma maior proporção de estádios embrionários mais maduros. Assim, conclui-se que o r-bST possivelmente potencializa os resultados da SOV, apesar de não atingir o objetivo final que seria um maior número de embriões, mesmo sendo visto nestas condições experimentais um aumento numérico dos mesmos. Mais estudos com relação a forma de aplicação e a dose utilizada são necessário, devido a alta variabilidade dos resultados.