A minimally invasive catheterization of the external jugular vein in suckling piglets using ultrasound guidance.

There is a growing interest for minimally invasive surgical procedures to improve experimental animal welfare. Minimally invasive catheterization procedures in pigs have been already developed using Seldinger technique but reproducibility is low, especially in young pigs. A novel method for a minimally invasive catheterization of external jugular vein was evaluated in suckling piglets of 21 days of age. Growth performance and haptoglobin concentration in plasma were measured throughout a four-week study in a group of seven catheterized piglets and a group of seven non-catheterized piglets. Catheterization was performed using Seldinger technique under continuous ultrasound monitoring for vein detection and needle insertion. The surgical procedure was quick and showed a great reproducibility. All catheters remained functional during the first week after catheterization. Catheterization in piglets did not significantly affect body weight (BW) and feed intake during four weeks after the surgical intervention compared to non-catheterized piglets (P > 0.10). Haptoglobin concentration in plasma was greater in catheterized piglets compared with non-catheterized piglets, with a significant increase over two weeks after catheter insertion (P < 0.05), suggesting the development of a chronic inflammation in catheterized piglets. This method can be easily performed in piglets with minimal effect on growth and feeding behaviour. Transposition to heavier pigs should be considered.

Effect of surgical or immune castration on postprandial nutrient profiles in male pigs.

To avoid boar taint before slaughtering, late castration by immunisation against gonadotrophin releasing hormone or immunocastration has been developed. The current study aimed at determining whether differences in feed efficiency between castrated male (CM), immune castrated (IM) and entire male pigs (EM) can be explained by differences in nutrient plasma profiles after a meal. In this study, 24 male pigs (n = 8/type) were enrolled between 14 to 19 weeks of age. Entire and IM pigs ate less and were more feed efficient than CM pigs (p < 0.05). The postprandial plasma profiles of glucose, insulin, urea and amino acids (AA) were determined before (d -6), just after (d 8) and well after (d 16) the decrease in testicular hormones in IM pigs. For each test day, pigs were fasted overnight and subsequently fed a small meal (400 g). On d -6, postprandial profiles of plasma glucose of IM pigs did not differ from the two other types of pigs. On d 8, EM pigs had a greater average plasma glucose concentration than IM and CM pigs (p < 0.05) but the profiles did not differ. On d 16, the differences between profiles of glucose suggest a lower clearance of glucose in EM compared with IM and CM pigs. Plasma insulin did not significantly differ between the three types. Plasma urea profiles did not differ between CM, EM and IC pigs on d -6 whereas CM pigs showed higher plasma urea concentrations than EM and IM thereafter (p < 0.01). Among AA, Lys plasma concentrations were greater in CM than in EM and IM pigs on d -6, d 8 and d 16 (p < 0.05), whereas on d 16 plasma Hypro concentrations were lower in CM than in EM and IM pigs (p < 0.05). The finding that plasma glucose profiles were modified by immunocastration much faster and earlier than urea and AA profiles, suggest that the decrease in testicular hormones impacted energy metabolism more rapidly than protein metabolism.