Perfil hormonal e avaliação ultrassonográfica hemodinâmica da glândula mamária de búfalas em diferentes categorias

• Ano de defesa: 2016
• Autor(a) principal: Dantas, Ariane [UNESP]
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Mammogenesis; Mammary blood flow; Evaluation Doppler; Hormone regulation; Dairy buffaloes; Mamogênese; Fluxo sanguíneo mamário; Avaliação Doppler; Regulação hormonal; Búfalas leiteiras
• Link de acesso: http://hdl.handle.net/11449/143067

The objective of this study was to delineate hemodynamic parameters and to evaluate its relationship with key hormones involved in mammogenesis of crossbred Murrah buffaloes in different physiological stages. We used 24 animals divided according to the category (n= 6): calves, heifers, pregnant and lactating females with early ages of zero, 12, 24 and 48 months, respectively, raised extensively. Every 28 days, Doppler ultrasound examinations, blood analysis and weighing were held over one year (for calves and heifers) and over 10 months (for pregnant and lactating females). There were determined resistivity index (RI) and pulsatility index (PI) and internal vessel diameter (ID) of the mammary arteries by ultrasound. Plasma concentrations of progesterone (P4), insulin-like growth factor 1 (IGF-I), insulin (IN), growth hormone (GH) and estradiol (17β-E2) were measured. We used repeated measures ANOVA, Spearman correlation and non-linear multiple regression considering 0.05 significance level. In calves and heifers, a reduction of RI and PI and increased ID (P<0.0001) from first to last month's assessment, however, there was no statistical difference in hemodynamic indices between the cranial and caudal mammary arteries. All heifers, RI correlation was detected with PI (r= 0.94; P<0.0001), and ID (r= -0.98; P<0.0001) and also PI with ID (r= -0.98; P<0.0001). In heifers RI also correlated with PI (r= 0.99; P<0.0001) and DI (r= -0.95; P<0.0001) and PI with the ID (r= - 0.98; P<0.0001). In pregnant and lactating females, the caudal mammary artery showed a significant difference to the hemodynamic indices, showing on pregnant females a lower RI (P<0.0001) and a higher ID (P<0.0001) during the five final three months of the study, respectively; and in lactating females, higher DI during the first seven months (P<0.0001). There was correlation of RI with the PI, in pregnant females (r= 0.98; P<0.0001) and in lactating females(r= 0.91; P<0.0006) and RI with ID in pregnant (r= -0.98; P<0.0001) and in lactating females (r= -0.95; P<0.0001). There was also a correlation between PI and ID, in pregnant (r= -0.98; P<0.0001) and in lactating females (r= -0.82; P<0.0046). In calves, the three Doppler parameters were significantly correlated with the plasma concentrations of IGF-I, GH and P4 (P<0.05), while in heifers correlation of PI, ID and only IGF-I and P4. In pregnant and lactating females, RI, PI and ID correlated with IGF-I, IN and 17β-E2, and in pregnant females, RI, PI and ID correlated well with P4 (P<0.05). Body weight had linear effect on RI (R2= 0.97; P= 0.0054) and ID (R2= 0.97; P= 0.0069) in heifers and quadratic influence on RI (R2= 0 97; P= 0.0116) and ID (R2= 0.97, P= 0.0001) in heifers, as well as quadratic effect on ID in pregnant (R2= 0.99, P<0.0001) and lactating females (R2= 0.95; P= 0.0002). Hemodynamic indices of mammary arteries reflected the assessed hormonal action and allowed to infer the mammary development of crossbred Murrah buffaloes during the different stages of growth, pregnancy and lactation.