Biomedical subjects

R H McCapes

Publications and source records attributed to R H McCapes.

31 records · Page 2Linked to original sources

PubMedDate not supplied

The Dillon Beach Project--a five-year epidemiological study of naturally occurring salmonella infection in turkeys and their environment.

A 5-year epidemiological study of naturally occurring salmonella infection 2 basic strains of turkeys and their environment was completed. Multiple generations of these turkeys, free from salmonella infection, were raised on a new commercial breeding ranch (the Dillon Beach Ranch) in California during a 31/2-year period. Eight salmonella serotypes eventually gained access to the ranch. Egg transmission and prior contamination of the premises were ruled out as the source of these infections. The most likely means of their introduction was physical transport into the ranch by contaminated feed, personnel, and/or equipment. Several serotypes of salmonella were isolated from pelleted feed delivered to the ranch, demonstrating its role in introducing infection. The low isolation rate from feed samples and environmental samples taken from many buildings indicates the need for intensive sampling as a reliable indicator of infection. The most severe and consistently detected infection occurred in young birds grown in forced-air-ventilated buildings. A total of 17,858 bacteriological cultures representing about 102,756 environmental, feed, and bird samples, and 93,930 serological tests on 46,977 serum samples, were run during the study.

Animal Feed↗

PubMedDate not supplied

Pasteurella multocida in wild mammals and birds in California: prevalence and virulence for turkeys.

Samples collected from the oropharynx of wild mammals and birds trapped on 36 turkey farms in California were evaluated for the presence of Pasteurella multocida. A total of 966 animals were collected from 18 premises that had experienced an outbreak of fowl cholera within the past 2-8 months; samples were collected from 16 of these 18 premises within 2-8 weeks of outbreak notification and while the infected flock was still present. A total of 939 animals were trapped from an additional 18 premises that had not reported any outbreaks of fowl cholera within at least 4 months, if ever. Forty-eight isolates of P. multocida, of a variety of somatic serotypes, were recovered from 6 species of mammals and 3 species of birds. On only 2 of 7 premises was the somatic serotype of the isolates obtained from wildlife the same as the isolate obtained from tissues of turkeys that had died of fowl cholera on the same premises. Tests for virulence to turkeys were conducted with 31 of the isolates. Seventeen of these isolates caused mortality in turkeys. Wide ranges in mortality rates and median times to death were observed.

Animals↗

PubMedDate not supplied

A descriptive study of fowl cholera in California meat turkeys: August 1985-July 1986.

One hundred sixty meat-turkey premises in California were monitored for outbreaks of fowl cholera from August 1985 through July 1986. Nearly 27 million turkeys in 720 flocks were at risk during the year. Fifty-three flocks of approximately 3 million turkeys on 34 different premises experienced confirmed fowl cholera outbreaks. The epidemic curve for the year indicated that the majority of outbreaks occurred in the late summer and fall, particularly in October. The incidence of outbreaks during this time was not significantly associated with seasonal variation in the size of the turkey population. The mean flock age at outbreak was 10.8 weeks, with a range of 5-18 weeks.

Animals↗

PubMedDate not supplied

Paramyxovirus type 3 (PMV-3) in California turkeys: serologic study of PMV-3 antibody with an enzyme-linked immunosorbent assay.

An enzyme-linked immunosorbent assay (ELISA) was developed for detecting paramyxovirus type 3 (PMV-3) antibody. This test had a higher sensitivity than the hemagglutination-inhibition test, and no cross-reactivity with various paramyxoviruses or avian pathogens was detected when the sera were tested diluted 1:200. The incidence of PMV-3 infection in California was studied by testing 2037 turkey sera from 174 meat and breeder flocks for the presence of PMV-3 antibody using the ELISA. The age at which the infection occurs was around 5 to 8 weeks for meat flocks and 10 to 12 weeks for breeder flocks. Infection with the PMV-3, as determined serologically, was more frequent than manifested cases of disease, and 95.2% of the flocks aged over 11 weeks had PMV-3 antibody. No typical manifestations of PMV-3 disease (respiratory disease plus drop in egg production) were observed, probably because of the early infection which occurred before laying age.

Animals↗

PubMedDate not supplied

Preincubation dipping of turkey hatching eggs. I. Effect of shell treatment on amount and variability of fluid intake.

Two techniques for egg-shell treatment were evaluated for their effects on the quantity and variability of the fluid absorbed by turkey hatching eggs subjected to the temperature-differential method of egg dipping. The use of pin or drill to pierce a uniform hole through the shell and membrane(s) on the large end of each egg caused a significant increase in the quantity of dip solution absorbed. Variability in fluid uptake by the eggs also was reduced significantly. Utilization of dilute acid to remove cuticle completely from the whole egg surface or partially from either end also had similar effects. The techniques described also permit and effective dipping procedure that does not require the preheating step.

Absorption↗

PubMedDate not supplied

Protection of day-old poults against Arizona hinshawii challenge by preincubation streptomycin egg treatment.

Poults were protected against challenge with Arizona hinshawii 7:1,7,8 inoculated into the yolk sac 30 hours post-hatching by preincubation streptomycin treatment of turkey eggs, administered by temperature-differential egg dipping in a solution composed of 250 ppm of a quaternary ammonium compound, 10 ppm of ethylenediaminetraacetate and streptomycin at 9 mg per ml. Mortalities at 17 hours and 22 days postchallenge were respectively 8% and 44% in poults from treated eggs vs 47% and 93% from untreated eggs. Liver isolation rates at 17 hours and 22 days postchallenge were respectively 0% and 16% in poults from treated eggs, vs 71% and 80% from untreated eggs.

Animals↗

PubMedDate not supplied

Effective control of a gentamicin-resistant Salmonella arizonae infection in turkey poults.

A gentamicin-resistant Salmonella arizonae isolate was identified as the cause of an unusually high early mortality rate in several flocks of poults produced by a primary turkey breeder. The company routinely dipped its hatching eggs in 500 ppm gentamicin before incubation and injected each poult at 1 day of age with 1 mg gentamicin. Mortality was reduced to normal, but S. arizonae was not eliminated by injecting the day-old poults with higher doses of gentamicin. S. arizonae was not isolated from sample normal-sized poults in treated groups when tetracyclines were used for antibiotic inoculation of day-old poults. Tetracyclines seemed to be completely effective only when a 5-mg subcutaneous injection per day-old poult was combined with an approximately equal dose in drinking water daily for 4 days, and therapy was accompanied by the culling of runts and other debilitated poults.

Animals↗

PubMedDate not supplied

Preincubation dipping of turkey hatching eggs. II. Effect of shell treatment on hatachability.

The effects of various egg-shell treatments on the hatchability of turkey eggs were investigated. Hatchability was not effected significantly by drilling a hole in the large end, or removing cuticle with dilute acid from the entire shell surface of from either end. Embryo deaths were increased significantly (P less than 0.005), however, by a pinhole pierced in the large end. Sealing the drill or pinhole with Duco cement did not significantly alter the hatchability. Hatchability of treated or untreated eggs was not effected adversely by dipping for 2.5 minutes after preheating to 36 C, or for 10 minutes without preheating.

Animals↗

PubMedDate not supplied

Effect of dietary protein deficiency on the performance of turkeys and chickens.

Two field occurrences of protein-deficiency disease were reported in turkeys and chickens. The disease caused unthriftiness, poor growth, and the exhibition of pica in flocks of 15-week-old pedigree large white turkeys, and it resulted in a sharp drop (18%) in egg production in a flock of 60-week-old white leghorn layers. In each case, the disease was cured by replacing the protein-deficient diet with a protein-sufficient one.

Animals↗

PubMedDate not supplied

Comb lesions and mortality patterns in white leghorn layers affected by Marek's disease.

Marek's disease was diagnosed as the cause of prolonged high mortality in two commercial flocks of white leghorn layers by gross and microscopic examination of affected tissues and by immunofluorescent study of live tumor cells using anti-Marek's disease tumor-associated surface antigen, anti-immunoglobulin M, and monoclonal antibodies. The disease was characterized by swollen, necrotic, lymphomatous combs and mortality that rose above normal at 28 weeks of age, peaked at 35-36 weeks, and returned to normal by 45-46 weeks.

Animals↗

PubMedDate not supplied

The effect of experimental turkey embryo infection with Mycoplasma meleagridis on weight, weight gain, feed consumption, and conversion.

Turkey poults were obtained from an earlier trial where hatchability performance of a group of embryos experimentally infected with Mycoplasma meleagridis [MM(+)] was compared with that of a group of uninfected cohorts [MM(-)]. In the present trial, post-hatch production parameters compared were weight, weight gain, feed consumption, feed conversion, culling, and mortality. Both toms and hens were monitored for 16 weeks, and a group of randomly selected toms was monitored for 22 weeks. Final liveweights and dressweights of hens were compared at 17 weeks, and those of the toms were compared at 23 weeks. Hens showed no significant (P less than 0.05) differences in the measured parameters during the 16-week period, nor did the initial population of toms, except in weight gain during the final period (weeks 12-16) and in final weight at week 16, which were significantly (P less than 0.05) greater in the MM(+) toms than in their MM(-) cohorts. Dressweights at slaughter of MM(+) hens were significantly greater than those of MM(-) hens, but liveweights of hens at slaughter and both liveweights and dressweights of toms at slaughter did not differ significantly. This inability of MM(-) turkeys to demonstrate a comparative advantage over MM(+) birds agrees with an earlier trial (4), in which MM(+) poults had weights superior to those of MM(-) cohorts during the first 3 to 4 weeks of life (4). These data indicate that the theory of superior performance in association with MM(-) birds must be reevaluated before the benefits derived from an M. meleagridis eradication program can be measured.

Animals↗

PubMedDate not supplied

The relationship between various production factors, condemnation, and downgrading in turkeys: factor analysis as a method of variable reduction.

Wholesomeness and grade inspection loss were monitored in a selected population of California turkeys. Of the several production variables normally measured in the production of meat turkeys, only "week of year place" and "temperature on date of processing" were found to be statistically significantly associated with "percent of flock receiving grade A." Factor analysis reduced the number of original variables, but some quality of the information resident in the original variables was lost.

Analysis of Variance↗

PubMedDate not supplied

Antibiotic egg injection to eliminate disease. I. Effect of injection methods on turkey hatchability and Mycoplasma meleagridis infection.

Mycoplasma meleagridis infection in turkey hatching eggs was eliminated by injecting eggs with a combination of tylosin and gentamicin. Hatched F1 and F2 progeny remained free of egg-transmitted infection. Contact exposure was experienced in one negative flock. Of the preincubation injection procedures studied, a drilled hole on the small end of the egg was the inoculation site easiest to administer and best tolerated by the embryo. The embryo can tolerate a dose of gentamicin sulfate injected at 10 days of incubation that would be toxic if administered before incubation. Requirements for maintaining progeny free of infection are discussed.

Animals↗