Interactions between viscerotropic velogenic Newcastle diseases virus and pet birds of six species. I. Clinical and serologic responses, and viral excretion

Clinical and serologic responses to a psittacine isolate of viscerotropic velogenic Newcastle disease virus (VVNDV) were evaluated in pet birds of six species: budgerigar, yellow-headed Amazon parrot, halfmoon conure, lesser hill mynah, black-headed nun, canary. The clinical response was most marked in the budgerigars, parrots, and conures, and only minimal in the nuns. Between post-exposure days (PED) 3 and 5 some birds developed ruffled plumage, conjunctivitis, and central nervous system dysfunction: ataxia, wing tremors, paralysis of the extremities, and tremors of the head accompanied by nodding and jerking. Mortality by PED 203 was 55% (29/52) in the halfmoon conures, 22% (23/105) in budgerigars, 29% (12/42) in parrots, and 21% (15/71) in nuns. The only clinical signs in canaries and mynahs were progressive death losses, respectively 25% (33/132) and 21% (10/48). The visceral lesions common in chickens with VVNDV were not observed in these six species. Canaries rapidly eliminated Newcastle disease virus (NDV), whereas it was detected for protracted periods in the oral and cloacal secretions of the other five species (for more than a year in parrots). Serologic evaluation by the hemagglutination-inhibition and neutralization tests also indicated prolonged NDV infections in 5 of the 6 species. The seroconversion rate observed in canaries was minimal (13%).     

Sow performance and maternal behaviour in organic and conventional herds

Abstract

The study evaluates the first three parities of 144 Swedish Landrace×Yorkshire sows from three certified organic and three conventional commercial piglet-producing herds. Sows and litters were weaned at seven and five weeks post partum (pp) in organic and conventional herds, respectively. Herdsmen judged sow behaviour and maternal ability at farrowing, two weeks pp and at weaning. Herdsmen collected registrations of litter size, litter weight and sow fat status at farrowing and at weaning. Piglet mortality and oestrous signs were registered continuously during the nursing period. Sows in organic herds were scored to be more cautious among piglets, and to have better nursing behaviour and maternal ability in early lactation than sows in conventional herds. Piglet mortality was higher in organic than in conventional herds. Oestrus during lactation was only observed among sows in organic herds, and sows showing oestrus during lactation were fatter at weaning.     

Mandibular fracture repair in a harbor seal

A 30-year-old captive female harbor seal (Phoca vitulina) bit down upon a metal ring within a hoop-net normally used to assist in securing the seal for routine physical examination. Radiographic examination performed under general anesthesia revealed a unilateral closed fracture of the rostral left mandible between the first and second premolar teeth. The rostral fragment was displaced ventrally and slight laxity of the mandibular symphysis was noted. The fracture was repaired surgically using an oral dental acrylic splint incorporating circumferential mandibular cerclage wire. The mandibular symphysis was stabilized using interdental wire between the right and left canine teeth. The fixation device was removed following evaluation of radiographs that showed signs of bony union 12-months postoperatively.     

Characterization of wheat-triticale doubled haploid lines by cytological and biochemical markers

Five wheat-triticale doubled haploid (DH) lines— M08, V209, DH220-14-2, DH696-3-4 and M16 —derived from anther culture of F₁s resulting from crosses involving hexaploid or octoploid triticale × hexaploid wheat, were characterized by cytological and biochemical markers. Cytological evidence from genomic in situ hybridization and C-banding indicated that DH lines M08 and V209 (2n= 42) each contained a pair of 1BL/1RS translocation chromosomes. DH220-14-2 (2n= 42) was also a translocated line with two pairs of chromosomes containing small fragments of rye. One of the translocation fragments carried the Sec-1R gene originating from the satellite region of 1RS; the origin of the other one remains unknown. DH696-3-4 (2n= 42) contained a 3D(3R) substitution. In M16 (2n= 44), three pairs of rye chromosomes, 3R, 4R and 6R, were present, 4R as an addition and 3D(3R) and 6D(6R) as substitutions. Biochemical, isozyme and storage protein markers confirmed the cytological conclusions. The advantages of transferring alien chromosomes or chromosome fragments into wheat and creating alien aneuploid lines by anther culture of hybrid F¹s are discussed.