Bacterial chondronecrosis with osteomyelitis in broilers: influence of sires and straight-run versus sex-separate rearing.

Two experiments (E1, E2) were conducted to compare the influence of sires (sire A on dam C vs. sire B on dam C) and straight-run versus sex-separate rearing on the incidence of bacterial chondronecrosis with osteomyelitis (BCO) in broilers. Fertile eggs from commercial breeder flocks were incubated and hatched at the University of Arkansas Poultry Research Hatchery. Male and female chicks were reared together (straight-run) or separately (sex-separate) in 3 × 3 m pens on litter or flat wire flooring with 65 (E1) or 60 (E2) birds per pen. Necropsies revealed lesions that are pathognomonic for BCO in ≥98% of the birds that became lame. The SigmaStat Z-test was used to compare cumulative BCO incidences through 8 wk of age. For birds reared on litter, the incidences of BCO were low regardless of cross or sex (range: 1.7 to 5.1%; P ≥ 0.6). Within a cross and sex, rearing the broilers straight-run versus sex-separate on wire flooring did not significantly affect the incidence of BCO. Significant incidences of BCO did not develop until after d 40. Males from the sire A cross developed a higher incidence of BCO than males from the sire B cross in E1 (27 vs. 17%, respectively; P = 0.009) but not in E2 (28.5 vs. 22.6%, respectively; P = 0.141). In both experiments, males from the sire A cross developed higher incidences of BCO than females from the sire B cross (27 vs. 11.9%, in E1; 28.5 vs. 14.8%, in E2). With the sexes pooled, broilers from the sire A cross consistently developed higher incidences of BCO than broilers from the sire B cross (21.4 vs. 14.9%, P = 0.005 in E1; 26.5 vs. 18.7%, P = 0.003 in E2). High susceptibilities to both femoral head (all femoral head necrosis = 66 to 85% incidences) and tibial head (all tibial head necrosis = 81 to 96% incidences) BCO lesions were demonstrated in lame birds from both sexes and crosses. This study supports a sire influence on the susceptibility of broilers to BCO. Sire lines can be chosen to reduce BCO susceptibility when broilers are grown beyond 6 wk of age.

Susceptibility of 4 commercial broiler crosses to lameness attributable to bacterial chondronecrosis with osteomyelitis.

Growing broilers on wire flooring provides an excellent experimental model for exposing susceptibility to lameness attributable to bacterial chondronecrosis with osteomyelitis (BCO). Two independent experiments (E1, E2) were designed to compare the susceptibilities of broilers from 4 commercial crosses (W, X, Y, and Z). The standard crosses (W and Y) grow rapidly at an early age, whereas high-yield crosses (X and Z) initially tend to grow more slowly. Chicks were obtained from a commercial hatchery for E1, or were hatched at the University of Arkansas Poultry Research Hatchery for E2. Males and females were reared together (E1; n = 360/cross) or separately (E2; n = 390/cross) in 3 × 3 m pens on litter or wire flooring (wire). Necropsies revealed lesions that were pathognomonic for BCO in ≥94% of the birds that became lame. The SigmaStat Z-test was used to compare cumulative lameness incidences at 8 wk of age. For birds reared on litter, lameness incidences were low and did not differ between crosses or sexes (range: 2.2 to 4.6%; P ≥ 0.6). When males were reared on wire, their lameness incidences (by cross) were E1 = 52% for W(b); 42% for X(c); 69% for Y(a), and 44% for Z(bc); E2 = 31% for W(b); 19% for X(c); 49% for Y(a); and 25% for Z(bc). For females reared on wire, the lameness incidences were E1 = 40% for W(b), 30% for X(c), 49% for Y(a), and 28% for Z(c); E2 = 16% for W; 15% for X; 16% for Y; and 15% for Z (ns). Accordingly, the hierarchical ranking for BCO susceptibility by broiler cross was X ≤ Z ≤ W < Y for males in E1 and E2, for females in E1, and for males and females pooled in E1 and E2. Standard broiler crosses developed higher incidences of lameness than high-yield crosses, implicating an association between rapid early growth and susceptibility to BCO. Rearing the females separately on wire in E2 led to uniformly low incidences of BCO, regardless of cross. Stress-mediated immunosuppression contributes to the pathogenesis of BCO; perhaps female broilers experience less social or competitive stress when reared separately from their male hatch mates.

Comparisons of sperm storage tubule distribution and number in 4 strains of mature broiler breeders and in turkey hens before and after the onset of photostimulation.

The biological basis of sustained fertility in broiler and turkey hens is their capacity to store sperm in the oviductal sperm storage tubules (SST) located in the uterovaginal junction. The objectives of this study were to determine if the numbers of SST varied between 4 strains of broiler breeders and determine the number of SST in the turkey before (less than 9 d of photostimulation) and after (up to 22 d of photostimulation and laying) photostimulation. No statistical differences were observed in SST numbers in the 4 strains of broilers examined or in turkey hens before and after the onset of egg production. The mean numbers of SST for broilers and turkeys were 4,893 and 30,566, respectively. We conclude that any differences between the fertility of the 4 broiler breeder strains examined cannot be explained by differences in SST numbers. However, differences in the duration of fertility between broilers and turkeys are, in part, related to their respective numbers of number of SST. Furthermore, we conclude that turkey SST are morphologically differentiated and functional before the onset of photostimulation and while the oviduct is morphologically undeveloped.

Wireless communication technology applied to disaster response.

Communication during disasters is frequently inadequate. In addition to having competent communication skills, medical responders must have access to adequate, effective, and reliable communications equipment. Wireless communication technologies are rapidly evolving. The medical community needs a basic understanding of existing and emerging technologies to fully exploit these new resources. Wireless communication technologies for disaster response include radio pagers, radios, cellular telephones, satellite communications, and personal communication services. This article explores concepts of each of these technologies, basic descriptions of current and future equipment, applications of the equipment to medical disaster response, and advantages and disadvantages of each technology.