Comparison of effects of a single dose of MHYOSPHERE® PCV ID with three commercial porcine vaccine associations against Mycoplasma hyopneumoniae (Mhyo) and porcine circovirus type 2 (PCV2) on piglet growth during the nursery period under field conditions.

Pigs routinely undergo stressful vaccination procedures, which are often unavoidable given the unavailability of safer alternatives, challenging animal welfare. The available vaccines for Mycoplasma hyopneumoniae (Mhyo) or Porcine circovirus type 2 (PCV2) are mostly administered intramuscularly in association to prevent Porcine respiratory disease complex (PRDC). MHYOSPHERE® PCV ID is the first vaccine protecting from both agents by intradermal route. This randomized, blind-field trial aimed to compare the effects of MHYOSPHERE® PCV ID with those of three different intramuscular associations of commercially available vaccines. A total of 7072 21-day-old piglets from 12 consecutive batches in one farm were randomly vaccinated with MHYOSPHERE® PCV ID (G1) or Ingelvac CircoFLEX® + Hyogen® (G2), Porcilis® PCV + M + PAC® (G3), and Porcilis® PCV + Hyogen® (G4). Growth performance during the nursery period and adverse reactions (ARs) after vaccine administration were monitored. Average Daily Weight Gain (ADWG) during the first 7 days post-weaning in G1 was 10.92, 3.03, and 20.08 g/day higher than in G2, G3, and G4, respectively, and 0.65, 4.06, and 9.58 g/day higher than in G2, G3, and G4 during the entire nursery period, respectively. G1 ADWG was significantly higher than G4 during both periods and significantly higher than G2 during the first 7 days post-weaning. Incidence of systemic ARs in G2 and G4 was 0.03% and 0.32%, respectively; none were recorded in G1 and G3. Replacing the usual intramuscular vaccination with MHYOSPHERE® PCV ID results in higher growth performance during the first weeks after weaning with no systemic ARs.

Structure of P46, an immunodominant surface protein from Mycoplasma hyopneumoniae: interaction with a monoclonal antibody.

Mycoplasma hyopneumoniae is a prokaryotic pathogen that colonizes the respiratory ciliated epithelial cells in swine. Infected animals suffer respiratory lesions, causing major economic losses in the porcine industry. Characterization of the immunodominant membrane-associated proteins from M. hyopneumoniae may be instrumental in the development of new therapeutic approaches. Here, the crystal structure of P46, one of the main surface-antigen proteins, from M. hyopneumoniae is presented and shows N- and C-terminal α/ß domains connected by a hinge. The structures solved in this work include a ligand-free open form of P46 (3.1 Šresolution) and two ligand-bound structures of P46 with maltose (2.5 Šresolution) and xylose (3.5 Šresolution) in open and closed conformations, respectively. The ligand-binding site is buried in the cleft between the domains at the hinge region. The two domains of P46 can rotate with respect to each other, giving open or closed alternative conformations. In agreement with this structural information, sequence analyses show similarities to substrate-binding members of the ABC transporter superfamily, with P46 facing the extracellular side as a functional subunit. In the structure with xylose, P46 was also bound to a high-affinity (Kd = 29 nM) Fab fragment from a monoclonal antibody, allowing the characterization of a structural epitope in P46 that exclusively involves residues from the C-terminal domain. The Fab structure in the complex with P46 shows only small conformational rearrangements in the six complementarity-determining regions (CDRs) with respect to the unbound Fab (the structure of which is also determined in this work at 1.95 Šresolution). The structural information that is now available should contribute to a better understanding of sugar nutrient intake by M. hyopneumoniae. This information will also allow the design of protocols and strategies for the generation of new vaccines against this important swine pathogen.

Effects of acepromazine on the stress response in Southern chamois (Rupicapra pyrenaica) captured by means of drive-nets.

This study was conducted to assess the stress response of Southern chamois (Rupicapra pyrenaica) to capture and physical restraint and the effects of acepromazine (a short-acting neuroleptic) on this response. Forty free-ranging Southern chamois were captured, injected intramuscularly with acepromazine (19 animals, randomly selected) or saline (the other 21 animals), and physically restrained for 3 h. Heart rate and body temperature were monitored with telemetric devices, and blood samples were obtained at capture and every hour thereafter to determine hematologic and serum biochemical parameters. The lower heart-rate variability, temperature, erythrocyte count, hemoglobin concentration, packed cell volume (PCV), and serum creatine kinase activity in the animals treated with acepromazine indicated that this agent reduced the adverse effects of stress. According to the differences in heart rate, erythrocyte count, hemoglobin concentration, PCV, lymphocyte count, and serum concentrations of glucose, creatinine, chloride, and potassium, alpha-adrenergic stimulation by catecholamines seemed to be stronger in females, whereas the adrenal-cortex reaction seemed to be stronger in males. The differences in erythrocyte parameters, temperature, serum creatine kinase activity, and serum concentrations of potassium and chloride indicated that acepromazine's beneficial effects were greater in females.

Transport stress in Southern chamois (Rupicapra pyrenaica) and its modulation by acepromazine.

Chamois have been translocated for more than 100 years but their stress response to transport remains to be elucidated. In this study, 21 free-ranging Southern chamois were captured, physically restrained and then transported. The animals were randomly injected intramuscularly with acepromazine (nine adult males, one adult female and one yearling male) or saline (five adult males, two adult females and three yearling males). Heart rate and body temperature were monitored with telemetric devices, and blood samples were obtained at capture, immediately before and immediately after transport to determine haematological and serum biochemical parameters. Heart rate and blood parameters (erythrocytes, haemoglobin, packed cell volume, leukocytes, monocytes, band neutrophils, lactate, muscular enzymes and creatinine) indicated that transport was more stressful than previous physical restraint. Acepromazine reduced the adverse consequences of transport stress, as demonstrated by heart rate, body temperature, cortisol, creatinine, muscular enzymes, urea, sodium and potassium.

Effect of venipuncture site on hematologic and serum biochemical parameters in marginated tortoise (Testudo marginata).

Blood samples were obtained from the dorsal coccygeal vein and the brachial vein of five adult (four females and one male) and two subadult males of marginated tortoise (Testudo marginata) and hematologic and biochemical parameters were compared. Significant differences were found for red blood cell count, hematocrit, hemoglobin concentration, total proteins, uric acid, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, alkaline phosphatase, calcium, and phosphorus, which were greater in the brachial vein samples. Hemodilution due to lymph was observed when collecting blood from the dorsal coccygeal vein, and it is thought to be the cause of the differences found. This research documented that the brachial vein is a more reliable and consistent venipuncture site than dorsal coccygeal vein in marginated tortoise.