Performance of early and late feathering broiler breeder females with different feeding regimens

1. Growth, reproductive characteristics and immunocompetence were evaluated in a line of broiler breeder females segregating at the sex-linked feathering locus when maintained on three feeding regimens with two forms of food in a factorial design. 2. Long-term obesity but not short-term weight gain had deleterious consequences for reproductive characteristics, response to sheep red blood cell antigen, resistance to Escherichia coli and livability. 3. Reproductive performance of early feathering females was superior to that of late feathering ones. Differences were attributed to an association between the allele for late feathering and an endogenous viral locus ev21, which encodes for avian leucosis virus. 4. Reproductive performance of breeders fed crumbles was superior to that of breeders fed a combination of crumbles and fines.

Maxillofacial trauma in severely injured patients

A study was made of maxillofacial trauma in seriously injured patients to determine the likely role of oral and maxillofacial surgeons working in the regional trauma centres proposed by the Royal College of Surgeons of England. There were 153 patients, aged 70 years or less, who sustained major trauma (injury severity score 16 or more) and were admitted directly to the accident departments of the Bristol Royal Infirmary or Derriford Hospital, Plymouth during 1989. Maxillofacial injuries occurred in 50 (33%) of these patients with lacerations present in 39, burns in 1 and facial bone fractures in 28 (18%); soft tissue abrasions and contusions were excluded. The aetiology, patterns of injury, surgical treatment and outcome were reviewed. The implications for the provision of maxillofacial surgical services in regional trauma centres is discussed.

Genetic variation in the incidence of pipped eggs in turkeys selected for low and high semen ejaculate volume

Genetic variation in embryonic mortality, expressed as embryos that pip their eggshell but do not hatch, was investigated in turkeys selected for low and high semen ejaculate volume (SEV). Through five generations (Generations 10 to 14, inclusive) mean heritability estimates for pipped eggs were .21 and .08 in the low- and high-SEV lines, respectively. Estimates of sire, dam, and within-hatch components of variance suggest greater environmental and maternal effects than genetic influences on the incidence of pipped eggs in turkeys.

Association of a chicken repetitive element with the endogenous virus-21 slow-feathering locus

The DNA sequences of an endogenous virus ev21-cell junction fragment (JFIL-1), and the pristine ev21 unoccupied region were analyzed. Comparisons of 3' proviral sequences of JFIL-1 with comparable regions of ev2, the prototype Rous-associated provirus (RAV-0), revealed minor single-base substitutions in the transmembrane domain of proviral envelope glycoprotein and the long terminal repeat of ev21. In the cell component of the JFIL-1, insertion of a 9-bp direct repeat and deletion of a guanine deoxynucleotide abolished HaeIII and BalI recognition sites that were present in the pristine region. Upstream from the insertion site, a large region was 71 and 75% homologous with dispersed chicken repetitive (CR1) elements associated with vitellogenin and very low density apolipoprotein II genes, respectively. Southern blot hybridizations and comparisons of CR1 motifs such as polypurine tracts, a tandem imperfect octamer, and 6-bp duplications indicated that this sex-linked, CR1 element (CR1ev21) may be the longest member of this family reported thus far.

Application of a locus-specific DNA hybridization probe in the analysis of the slow-feathering endogenous virus complex of chickens

To investigate further the sex-linked, slow-feathering (SF) locus, a DNA hybridization probe that flanks the integration site of endogenous virus ev21 was used to probe Southern blots from a variety of commercial SF White Leghorn (WL), broiler, and endangered lines. After HaeIII digestion of DNA from SF WL, the 5' and 3' provirus-cell junction fragments were seen in addition to a 2.5-kb fragment of cell sequences that was homologous with the viral integration region. The latter polymorphism, which appeared to represent sequences duplicated after integration of EV21, was designated unoccupied repeat URa. Among SF broiler crosses, the same provirus-cell junction fragments were found but the pristine region that represented the 1.6-kb proviral URb was also found. Only URb was found among rapid-feathering (RF) chickens, regardless of breed. Although there was marked (greater than 95%), agreement between the presence of ev21-cell; junction fragments and the SF phenotype among both WL and broilers, Southern blots of DNA from a few commercial SF broiler chickens lacked ev21 junction fragments but some RF revertants harbored ev21 junction fragments. These anomalies suggest that ev21 may not be the sole determinant of the SF phenotype.

The influence of ev6 on the immune response to avian leukosis virus infection in rapid-feathering progeny of slow- and rapid-feathering dams

Endogenous virus (EV) locus ev6 encodes only virus envelope glycoprotein. The influence of ev6 on the immune response to contact infection with hatchmates infected with avian leukosis virus (ALV) was compared in replicate hatches. The ALV Subgroup E-resistant, rapid-feathering (RF) female chickens produced by slow-feathering (SF) and RF dams with and without ev6 were exposed at hatch to hatchmates infected with ALV Subgroup A (Strain RPL-40). The RPL-40 viremia, shedding, and virus neutralizing antibodies were measured among pullets from two hatches at 22 wk of age. Although significant (P less than .05) differences between hatches in the immune response to contact infection were noted among ev6+ pullets, significantly fewer ev6+ pullets seroconverted than their ev6- hatchmates. At 22 wk of age, significantly more lymphomas were also found among ev6+ pullets than among ev6- hatchmates. In flocks wherein both parents and progeny were homozygous resistant to Subgroup E virus, there was no deterimental maternal effect on RF progeny from SF dams that carried ev21. These results also confirm that selection for genetic cellular resistance to Subgroup E ALV infection eliminates congenital transmission of EV21.

Prospective comparison of peritoneoscopic and surgical implantation of CAPD catheters

Prospectively collected data were analyzed comparing surgically and peritoneoscopically placed peritoneal dialysis catheters in 88 patients. Peritoneoscopically placed catheters were found to survive longer than surgically placed ones. Rates of exit site infection and pericatheter leaks were found to be similar with both techniques.

Influence of maternal antibody on avian leukosis virus infection in White Leghorn chickens harboring endogenous virus-21 (EV21)

Slow-feathering (SF) white leghorn dams harboring the endogenous viral gene ev21, which encodes for complete endogenous virus-21 (EV21), and rapid-feathering (RF) dams lacking EV21 were immunized with a live field strain of avian leukosis virus (ALV) subgroup A. One group of SF dams and one group of RF dams were not immunized and were maintained to produce chicks lacking maternal ALV antibody. When the SF dams were crossed with line 15B1 males, the resulting male progeny were SF, EV21-positive, and the females were RF, lacking EV21 or congenitally infected with EV21. EV21-positive and -negative progeny of immunized and unimmunized SF and RF dams were exposed to ALV at hatching. Viremia, antibody development, cloacal shedding, and tumors in chickens lacking EV21 were compared with those in chickens with EV21. Congenital transmission of EV21 from SF dams to RF female chicks was significantly higher in immunized dams than in unimmunized dams. Maternal ALV antibody delayed infection with ALV and reduced viremia and cloacal shedding of virus in progeny. The effect of maternal antibody on ALV infection was much more pronounced in progeny lacking EV21 than in progeny harboring EV21. The data suggest that the development of ALV infection and tumors may be influenced by status of infection with EV21 and by the immune status of dams.

Home blood pressure monitoring for mild hypertensives

A clinical trial of 204 untreated patients with mild hypertension was conducted to assess the effect of home blood pressure monitoring on blood pressure level, pharmacologic treatment, reduction of risk factors, and use of health services. After 1 year, no statistically significant differences were found between the treatment and control groups. The findings indicate that, while home blood pressure monitoring may be useful, it has no measurable short-term impact on these aspects of blood pressure management for patients with mild hypertension.

Molecular analysis of endogenous virus ev21-slow feathering complex of chickens. 1. Cloning of proviral-cell junction fragment and unoccupied integration site

Sex-linked slow-feathering gene, K, is genetically associated with the presence of an avian endogenous retrovirus ev21 in White Leghorns (WL). An EcoRI fragment corresponding to the endogenous virus ev21-cell junction fragment and a fragment homologous to the proviral unoccupied site (US) were cloned, respectively, from genomic DNA libraries of two WL chickens: an ev21-only female and an ev-negative male. A 1.7-kilobase pairs (kbp) fragment cleaved from the cloned proviral US by the HaeIII restriction endonuclease was the most informative probe to molecularly characterize the occupied and unoccupied integration sites of ev21 locus. Restriction fragment length polymorphism analysis of slow-feathering (SF) and rapid-feathering (RF) chickens from various commercial breeds, using the US HaeIII 1.7-kbp probe, indicated that the complete genetic association between ev21 and SF phenotype is common among other lines of SF chickens and was not restricted to WL. It was also shown that there was at least one additional DNA region highly homologous to DNA sequences flanking the EV21 integration site in the chicken genome. In SF birds of either sex this additional repeat was distinguishable from the site occupied by ev21 (OR) and represents an unoccupied repeat (UR). Analysis of DNA from RF revertant females showed novel patterns of reversion. In Type I RF revertants, RF is associated with the complete excision of proviral ev21 DNA sequences. In Type II revertants, the UR homologous to the cell sequences flanking ev21 integration site is excised, but proviral ev21 sequences remain intact. A hypothesis to explain these types of reversion is suggested. It postulates a close association between OR and UR on the Z chromosome.

Trauma scoring methods

Trauma scoring methods are recommended for use in the management of trauma patients. Currently used methods are reviewed for their use in triage, the determination of injury severity and the assessment of prognosis and outcome in comparative evaluation of trauma care within or between institutions.

Interactions between endogenous virus loci ev6 and ev21. 1. Immune response to exogenous avian leukosis virus infection

The effects of ev6, ev21, sex, and hatch, were studied with respect to avian leukosis virus (ALV) viremia, cloacal shedding, and antibody response among RPL-40 virus-infected White Leghorns that carried ev6 and ev21 in all combinations. Among the four possible ev genotypes, chickens that carried only ev21 were the most immunologically tolerant to RPL-40 infection. Incidence of RPL-40 viremia was lowest among hatchmates that lacked both ev genes. Analysis of variance indicated significant interactions between ev6 and ev21 with respect to all responses. Among ev21+ slow-feathering (SF) chickens, the incidence of viremia and shedding of RPL-40 was reduced in the presence of ev6 when compared with ev6- hatchmates. Conversely, among ev21- rapid-feathering (RF) chickens, ev6 significantly enhanced the incidence of RPL-40 viremia when compared with ev6- hatchmates. The endogenous virus, ev6, markedly reduced recovery of the endogenous virus (EV21) from plasmas of slow-feathering chickens. When both flocks were terminated at 21 wk of age, significantly more ev21+ SF females had died from or developed RPL-40-induced tumors than ev21- hatchmates.

Interactions between endogenous virus loci ev6 and ev21. 2. Congenital transmission of EV21 viral product to female progency from slow-feathering dams

The influence of the endogenous virus ev6 on congenital transmission of EV21, the infectious viral product encoded by locus ev21, and the immune response to exogenous avian leukosis virus (ALV) infection was studied in rapid-feathering (RF) female progeny from four classes of slow-feathering (SF) (ev21+ and RF (ev21-) dams with and without ev6. Apart from transmitting infectious EV21 and ev6 to progency, dam ev genotype did not influence the immune response or shedding of RPL-40. The endogenous virus envelope glycoprotein encoded by ev6, however, completely restricted shedding and congenital transmission of infectious endogenous virus EV21, from SF dams. After 19 wk of exposure to ALV strain RPL-40 infected cage mates, only 11% of the congenitally infected female progeny mounted neutralizing antibodies against RPL-40, whereas 73% of their noncongenitally infected sisters seroconverted. More ev6+ female progeny, however, were shedders of RPL-40 and developed tumors than ev6- sisters. Among progeny from the four classes of dams, EV21 congenitally infected hens had the highest incidence (31%) of RPL-40-induced tumors.

Ankle arthrodesis in the rheumatoid patient

We studied 11 patients with severe rheumatoid arthritis of the ankle joint who underwent arthrodesis employing the Charnley technique. Results of the procedure were assessed using the Fries score and the ankle evaluation grading system of Mazur et al. Four patients (36%) suffered pin-track sepsis. Three patients also showed delayed union, but sound bony fusion was eventually achieved in all patients.

Monocondylar fractures of the femur: a review of 13 patients

We reviewed 13 patients with monocondylar fractures of the femur. Undisplaced fractures may require extensive radiological investigation to visualize the fracture. Anatomically reduced fractures may displace when treated non-operatively. Joint line incongruity and resultant callus formation produces an abnormal condylar profile leading to early secondary osteoarthritis. We recommend internal fixation in all patients with monocondylar fractures.

Arthrodesis of the metacarpo-phalangeal joint of the thumb: a review of 42 cases

42 arthrodeses of the metacarpo-phalangeal joint of the thumb in 34 patients have been reviewed at a mean of 22.5 months after operation. Where bone stock allowed, Omer's chevron arthrodesis was used. 83% of these operations were judged to have been successful by our patients, most of whom were suffering from inflammatory joint disease. Some patients had very poor pinch pressures when reviewed, but only those with persistent instability or pain were disappointed. All arthrodeses were fixed in flexion; although the angle varied, no ideal position was identified.

Arthrodesis of the metacarpo-phalangeal joint of the thumb: a review of 42 cases

42 arthrodeses of the metacarpo-phalangeal joint of the thumb in 34 patients have been reviewed at a mean of 22.5 months after operation. Where bone stock allowed, Omer's chevron arthrodesis was used. 83% of these operations were judged to have been successful by our patients, most of whom were suffering from inflammatory joint disease. Some patients had very poor pinch pressures when reviewed, but only those with persistent instability or pain were disappointed. All arthrodeses were fixed in flexion; although the angle varied, no ideal position was identified.

Potentiation by the lithium ion of morphogenetic responses to a Xenopus inducing factor

We have cultured explants of Xenopus blastular animal cap tissue from embryos that had received an earlier treatment with LiCl and from their untreated siblings, in various concentrations of XTC-cell-derived mesoderm-inducing factor (XTC-MIF, Smith, 1987; Smith et al. 1988). The pretreatment with lithium that we used transforms later morphogenesis in the whole embryo to give radialized body forms with anterior/dorsal levels of structure grossly over-represented. In addition, animal caps from ‘Li+’ embryos were allowed to develop without exposure to in vitro MIF (Li+ controls) and compared with normal uninduced control explants, and explants were made from normal early blastulae but given various initial treatments with LiCl in culture. The results confirm that the lithium ion itself will not induce mesoderm in competent, animal cap tissue of Xenopus. It does, however, enhance the responsiveness of this tissue to XTC-MIF, in a way that parallels its recently reported effect in the case of another mesoderm inducer of different character, bFGF (Slack et al. 1988). The effects observed are sufficient to imply that the altered body pattern that follows lithium treatment, in whole embryos, could be caused by modulation of the responses to an unaltered pattern of in situ inductive stimuli. We also observe evidence that appreciable inductive signals reach animal pole tissue beyond the limits of mesoderm formation in normal development. Relatively low concentrations of MIF prevent the development of an epidermis-specific marker in dissociated blastular animal cap cells (Symes et al. 1988). When such experiments are repeated in relation to the lithium pretreatment of embryos, such treatment is seen to have sensitized the cell population, so that the MIF concentration range that assures complete suppression of the marker is reduced. The results are discussed in relation to induction considered as pattern formation.

Milk production, weight changes and blood biochemical measurements in dairy cattle receiving recombinant bovine somatotropin

Fortnightly injections with 500 mg (1.4 ml) of recombinant bovine somatotrophin in 20 dairy cows and heifers at 80 +/- 7 days after calving resulted in increasing milk yields, compared with paired control cows, for three to four days. The advantage was maintained for a further seven to eight days with a decline occurring during the last two to three days before the next injection. The milk yield did not return to the level of the control cows, and the gap between the lactation curves widened as treatment continued, until two to three weeks after the last injection. The cows' response to treatment was greater than the response to heifers. Blood beta-hydroxybutyrate concentrations reflected the higher energy requirements of the treated animals and the weight loss of the treated heifers. Urea-nitrogen concentrations were significantly lower in the treated animals, suggesting that they utilised protein more efficiently. Treated animals had higher inorganic phosphate concentrations, although they remained within the normal ranges. Differences in calcium, magnesium, albumin and globulin concentrations were either statistically or practically not significant.

Genetic cellular resistance to subgroup E avian leukosis virus in slow-feathering dams reduces congenital transmission of an endogenous retrovirus encoded at locus ev21

The gene ev21, which encodes an infectious endogenous subgroup E avian leukosis virus (ALV-E), designated EV21, is closely linked to the sex-linked, slow-feathering (SF) gene K. To address the relationship between congenital transmission of EV21 and host susceptibility to ALV-E infection, SF roosters that were heterozygous for the dominant gene for susceptibility to ALV-E were mated with ev-negative rapid-feathering (RF), subgroup E-resistant dams to produce SF and RF progeny. The SF female progeny that were heterozygous ALV-E susceptible were viremic at hatch and, when mature, consistently shed the ALV group-specific antigen, p27, in the egg albumen they produced. In contrast, SF females that were homozygous ALV-E resistant were neither viremic at hatch nor shedders of ALV p27. Infectious ALV-E assays of progeny from susceptible and resistant SF dams confirmed that maternal cellular resistance to ALV-E limited congenital transmission of EV21. It is proposed that, in progeny, immunologic tolerance toward exogenous ALV infection due to congenital transmission of antigenically related endogenous viruses may be abrogated by selection for cellular resistance to ALV-E in SF lines used as female parents of feather-sexed crosses.