Comparative analysis of laparoscopic and ultrasound-guided biopsy methods for gene expression analysis in transgenic goats.

The present study aimed to compare laparoscopic (LP) and ultrasound-guided (US) biopsy methods to obtain either liver or splenic tissue samples for ectopic gene expression analysis in transgenic goats. Tissue samples were collected from human granulocyte colony stimulating factor (hG-CSF)-transgenic bucks and submitted to real-time PCR for the endogenous genes (Sp1, Baff, and Gapdh) and the transgene (hG-CSF). Both LP and US biopsy methods were successful in obtaining liver and splenic samples that could be analyzed by PCR (i.e., sufficient sample sizes and RNA yield were obtained). Although the number of attempts made to obtain the tissue samples was similar (P > 0.05), LP procedures took considerably longer than the US method (P = 0.03). Finally, transgene transcripts were not detected in spleen or liver samples. Thus, for the phenotypic characterization of a transgenic goat line, investigation of ectopic gene expression can be made successfully by LP or US biopsy, avoiding the traditional approach of euthanasia.

Mensurações ultrassonográficas da cisterna da glândula mamária de caprino transgênico / Ultrasound measurements of the mammary gland of transgenic hormone-induced lactating goat

Milk production of transgenic does was evaluated by ultrasound measurements of the mammary gland. Two Canindé goats, which were nine months of age were used in the trial, one non-transgenic or other transgenic for hG-CSF. For hormone-induced lactation, animals were given estradiol (0.25mg/kg, IM), progesterone (0.75mg/kg, IM), and prednisolone (0.4mg/kg, IM). Ultrasonographic exams were carried out during milking, using a Falcon 100 ultrasound equipment with a 5MHz convex probe and were performed by the same operator. The results were expressed as mean±standard error. The maximum greater length and shorter length of the cistern were respectively 5.14cm and 1.36cm for the transgenic animal and 7.28cm and 2.25cm for non-transgenic, which is consistent with the maximum milk volume produced. The relationship between the average area of cisterns and milk yield was expressed as a linear correlation curve, with a correlation coefficient significantly positive for both transgenic (Y=-1.1314+10.8538*x; r=0.97) and non-transgenic (Y=-21.7551+18.3634*x; r=0.97) animals. In conclusion, the ultrasound is a practice and appropriate technique to evaluate the cisterns in ruminant udders in transgenic animal.