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1.
Poult Sci ; 100(3): 100914, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33518328

RESUMO

Use of a live coccidiosis vaccine has become an increasingly common method to control coccidiosis, especially in antibiotic-free broiler production. The Inovocox EM1 vaccine (EM1) is recommended for the vaccination of embryonated broiler hatching eggs between 18.0 and 19.0 d of incubation (doi). This allows for earlier acquisition of immunity to wild-type coccidia. However, it is unclear whether the difference in embryo age at the time of in ovo injection can influence the effect of the vaccine during grow-out as well as if the growth performance of broiler chickens is affected. Therefore, the objective of the study was to evaluate the effects of 2 injection ages (18.5 and 19.0 doi) and 3 injection types (noninjected, diluent, and vaccine) in a 3 × 2 factorial design, consisting of 10 replicates per treatment (60 treatment-replicate groups). There was a significant effect of injection age on BW at 0, 14, and 35 d after hatch, with a difference in the BW of birds belonging to the 18.5 and 19.0 doi groups up to day 35 after hatch. There was a significant effect of injection type on BW gain, feed intake, and FCR between 0 and 28 d after hatch. Between 0 and 35 d, FCR was lower in the vaccine-injected group in comparison with the noninjected and diluent control groups. Furthermore, total intestine coccidia and lesion indices were higher in the vaccine-18.5 treatment group in comparison with the diluent-18.5 treatment group at 28 d. In conclusion, hatchling weight was affected by injection age, and this subsequently affected growth performance. Furthermore, intestinal coccidia cycling peaked at 28 d, resulting in a reduction in growth performance through 28 d and subsequent compensatory growth by 35 d. There was no significant difference in coccidiosis cycling between the vaccine-18.5 and vaccine-19.0 doi treatment combination groups.


Assuntos
Coccidiose , Vacinas Protozoárias , Animais , Galinhas , Coccidiose/prevenção & controle , Coccidiose/veterinária , Óvulo , Vacinação/veterinária
2.
Poult Sci ; 95(10): 2306-13, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27433009

RESUMO

The relationships of eggshell, air cell, and embryo cloacal temperatures in Ross × Ross 708 broiler hatching eggs were determined. Twenty eggs were weighed and set on each of 3 tray levels of a single incubator. Eggshell temperature (EST) of the eggs were recorded once in the morning (AM) and afternoon (PM) between 0 and 19 d of incubation (DOI) using an infrared thermometer (IRT). All eggs were candled and a transponder was implanted in the air cell of eggs containing live embryos (12 per tray level) at 12 DOI. At 19 DOI, transponders were implanted in the cloaca of live embryos from those same eggs. Air cell temperature (ACT) and EST readings were recorded once in the AM and PM between 12 and 19 DOI, and ACT and cloaca temperature (CLT) readings were recorded every 6 h between 19 and 21 DOI. The EST and ACT readings between 13 and 19 DOI were positively correlated. However, their respective mean temperatures between 13 and 19 DOI differed. The EST and ACT were not significantly influenced by tray level. Nevertheless, a main effect due to location (eggshell vs. air cell), and an interaction between DOI and time of day (AM and PM) in the 13 to 19 DOI interval were observed. Furthermore, an interaction was observed between location (air cell and cloaca) and the 6 h sequential time periods in the 19 to 21 DOI interval. However, across the entire 19 to 21 DOI interval, mean ACT and CLT were not significantly different, and were positively correlated. These data suggest that ACT readings are higher than those of EST during the last half of incubation, and that between 13 and 19 DOI, ACT readings may have the potential for use as a minimally invasive method by which to more accurately estimate the true core body temperature of broiler embryos. The effects of this method on hatchability and post-hatch performance need determination to better establish its practicality.


Assuntos
Galinhas/fisiologia , Cloaca/fisiologia , Casca de Ovo/fisiologia , Óvulo/fisiologia , Animais , Embrião de Galinha , Telemetria/veterinária , Temperatura
3.
Poult Sci ; 95(5): 997-1004, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26976904

RESUMO

The University of Georgia maintains two meat-type chicken control strains: the Athens Random Bred (ARB) and the Athens Canadian Random Bred (ACRB). The Athens Random Bred was developed from colored plumage commercial meat chicken strains in 1956. The ACRB is a replicate population of the Ottawa Meat Control strain which was developed in 1955 from white plumage commercial meat-type chickens. These genetic lines have been extremely valuable research resources and have been used extensively to provide comparative context to modern meat-type strains. The ACRB may be the oldest pedigreed control commercial meat-type chicken still in existence today. This paper reviews the history of the breed backgrounds for both control populations and reviews research utilizing the ACRB.


Assuntos
Galinhas/genética , Galinhas/fisiologia , Animais , Cruzamento , Galinhas/anatomia & histologia , Crista e Barbelas , Plumas , Pigmentos Biológicos
4.
Poult Sci ; 93(12): 2953-62, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25352681

RESUMO

A flock of the Athens Canadian Random Bred (ACRB), a 1955 meat-type chicken control strain, was raised alongside a flock of 2012 Cobb 500 fast feathering high-yielding broilers to determine selection changes over the past 57 yr. All birds were reared under management practices appropriate for the Cobb 500. Birds were weighed weekly and processed at 6, 8, and 10 wk. Whole carcass, carcass parts, and organs were weighed. Modern broilers outweighed ACRB at every age, ranging from 3.7 to 4.7 times the size of the ACRB. All parts and organs were compared as a percentage of live fasted BW. The ACRB had significantly heavier feet, wings, internal organs, and feathers. The modern Cobb broiler had double the breast and larger leg muscles and had a significantly greater fat pad. Despite the larger muscle mass, the supply organs, the heart and lungs, were significantly smaller in the Cobb broiler than the ACRB as a percentage of BW. Relative size of supply and other vital organs should be given consideration for genetic selection of the future broiler. Comparisons of ACRB weights and organ percentages with past published data indicates that the ACRB remains a consistent control strain.


Assuntos
Composição Corporal/fisiologia , Galinhas/crescimento & desenvolvimento , Galinhas/genética , Tecido Adiposo , Animais , Composição Corporal/genética , Cruzamento , Galinhas/anatomia & histologia , Galinhas/metabolismo , Ingestão de Líquidos , Ingestão de Alimentos , Metabolismo Energético/genética , Metabolismo Energético/fisiologia , Feminino , Masculino , Seleção Genética , Fatores Sexuais
5.
Poult Sci ; 93(9): 2151-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25002554

RESUMO

Athens Canadian Random Bred (ACRB) chickens, a 1955 meat-type control strain, were incubated with the 2013 Cobb 500 broiler to determine differences in egg composition, conductance values, incubation duration, hatch performance, and yolk utilization. Unincubated ACRB eggs had greater percentage solids than Cobb 500 eggs. The ACRB eggs had a greater solid portion as yolk, whereas the Cobb 500 devoted more solid percentage to albumen. Percentage shell was not different between the strains, but ACRB eggs had 2.7% greater percentage moisture loss after 18 d of incubation than Cobb 500 eggs. Conductance, conductance constant, and conductance standardized to a 100 g egg weight basis were all higher for ACRB eggs than Cobb 500 eggs at 12 and 18 d of incubation. The Cobb 500 chicks hatched 6 h earlier than ACRB chicks. The Cobb 500 incubation duration was 498 h, and the ACRB incubation duration was 504 h. There was no difference between the strains for percentage infertile eggs, embryonic mortality, hatchability, or salable chicks. The ACRB chicks hatched with a smaller dried residual yolk sac as a percentage of chick weight compared with the Cobb 500. Both strains had an average relative yolk-free chick weight of 61% of average initial egg weight. Thus the Cobb 500 eggs had decreased gas exchange across the eggshell, which may have contributed to the earlier hatch and decreased yolk utilization. Modern Cobb 500 broiler embryonic metabolism appears to have either become more dependent on albumen rather than yolk or has become more efficient with yolk reserves during development. Broiler hatch performance does not appear to have changed over the past 58 yr.


Assuntos
Galinhas/fisiologia , Casca de Ovo/fisiologia , Óvulo/fisiologia , Saco Vitelino/metabolismo , Animais , Peso Corporal , Galinhas/genética , Galinhas/crescimento & desenvolvimento
6.
Poult Sci ; 92(12): 3096-102, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24235216

RESUMO

Skewing the sex ratio at hatch in commercial poultry would be economically beneficial to the poultry industry. The existence of temperature-dependent sex determination is uncertain in birds. This experiment investigated if incubation temperatures skew sex ratios of commercial broilers. Three incubators were each set at a hot (38.3°C), standard (37.5°C), or cool (36.7°C) single-stage incubation temperature one time over 3 trials to eliminate incubator effect as a Latin square design. Sex ratios of hatched chicks and dead embryos were monitored. In one trial, embryo weights were evaluated. The percentages of male hatched chicks did not differ based on incubation temperature (P = 0.4486; 49.5% in the hot treatment, 51.4% at standard temperature, and 49.8% in the cool treatment). The percent hatch of eggs set was lower in the hot treatment (83.6%) than the standard (93.5%) and cool (91.6%) treatments (P < 0.0001) with greater late embryonic mortality in the hot treatment (P < 0.0001); however, the sex ratio of dead embryos did not differ among treatments (P = 0.9863). Pooled data of embryo mortality found no sex-biased embryo mortality with a female/male sex ratio of 1.22:1 (χ(2) = 1.27; P = 0.2596). Embryos from the hot treatment were heavier than those from the standard treatment by d 14 of incubation and were heavier than the embryos from the cool treatment by d 9 of incubation (P < 0.0001). These data indicate that incubation temperature affects embryonic mortality and embryonic growth rate, but it does not affect the sex ratio of broiler chickens. Additionally, no evidence was found for sex-biased embryo mortality in commercial broilers even at the incubation temperatures of this study.


Assuntos
Embrião de Galinha/fisiologia , Galinhas/fisiologia , Reprodução , Animais , Embrião de Galinha/crescimento & desenvolvimento , Galinhas/crescimento & desenvolvimento , Feminino , Longevidade , Masculino , Distribuição Aleatória , Caracteres Sexuais , Razão de Masculinidade , Temperatura
7.
Am J Vet Res ; 62(6): 968-73, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11400858

RESUMO

OBJECTIVE: To compare radius of curvature along the ulnar trochlear notch of Rottweilers and Greyhounds to determine whether morphologic differences exist that may contribute to the cause and pathogenesis of fragmented coronoid process in Rottweilers. SAMPLE POPULATION: Paired elbow joints from 13 Rottweilers and 14 Greyhounds. PROCEDURE: Elbow joints were radiographically scored on the basis of severity of osteoarthritic lesions. The articular contour of each ulnar trochlear notch was digitized. The radius of curvature at defined points along the ulnar trochlear notch was compared between breeds. RESULTS: Radius of curvature of the ulnar trochlear notch was not a constant function of arc length in either breed but had a consistent characteristic appearance in both breeds. Radius of curvature was greatest at each end of the ulnar trochlear notch and had 2 peaks in the midportion of the notch in both breeds. These peaks occurred farther distally in the notch and were larger in Rottweiler ulnae than Greyhound ulnae. A significant difference in mean radius of curvature was detected between breeds at these peaks. Greyhounds had significantly greater mean radius of curvature at the end of the medial coronoid process, compared with Rottweilers. CONCLUSIONS AND CLINICAL RELEVANCE: Radius of curvature of the ulnar trochlear notch is a complex function of arc length in Rottweilers and Greyhounds. The waveform has a consistent characteristic appearance in both breeds. Although significant differences were identified between breeds, associations between these differences and cause or pathogenesis of fragmented coronoid process in Rottweilers were not apparent.


Assuntos
Doenças do Cão/etiologia , Cães/anatomia & histologia , Artropatias/veterinária , Articulações/anatomia & histologia , Ulna/anatomia & histologia , Animais , Doenças do Cão/diagnóstico por imagem , Membro Anterior/anatomia & histologia , Membro Anterior/diagnóstico por imagem , Membro Anterior/fisiologia , Artropatias/diagnóstico por imagem , Artropatias/etiologia , Articulações/fisiologia , Radiografia , Ulna/diagnóstico por imagem , Ulna/fisiologia
8.
J Am Vet Med Assoc ; 218(6): 897-9, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11294314

RESUMO

Differential diagnoses for hyponatremia with concurrent hyperkalemia should include hypoadrenocorticism. Renal failure, chylothorax, and gastrointestinal tract disorders may also cause abnormally low serum sodium:potassium ratios. The ACTH stimulation test is the gold standard for diagnosis of hypoadrenocorticism.


Assuntos
Insuficiência Adrenal/veterinária , Doenças do Cão/diagnóstico , Hiperpotassemia/veterinária , Hiponatremia/veterinária , Complicações na Gravidez/veterinária , Insuficiência Adrenal/diagnóstico , Animais , Diagnóstico Diferencial , Cães , Eletrólitos/sangue , Feminino , Hiperpotassemia/diagnóstico , Hiponatremia/diagnóstico , Gravidez , Complicações na Gravidez/diagnóstico
9.
J Small Anim Pract ; 41(7): 312-5, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10976627

RESUMO

Arthrodesis of the right stifle was performed in a 21 kg German shepherd dog that had sustained a comminuted fracture of the lateral femoral condyle as a result of a gunshot wound. The arthrodesis was stabilised with a circular external skeletal fixator. A simplified technique to facilitate creation of the osteotomies of the femur and tibia, and positioning of the stifle at the desired angle, is described. Compression of the subchondral bone surfaces of the distal femur and proximal tibia was achieved using tensioned coiled transarticular Kirschner wires. Arthrodesis of the stifle was confirmed radiographically 21 weeks following surgery, and the fixator was removed. After union of the arthrodesis and removal of the fixator, the dog was fully weightbearing when standing or walking, and intermittently weightbearing or non-weightbearing at faster gaits.


Assuntos
Artrodese/veterinária , Cães/lesões , Fixadores Externos/veterinária , Joelho de Quadrúpedes/cirurgia , Ferimentos por Arma de Fogo/veterinária , Animais , Artrodese/reabilitação , Cães/cirurgia , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Masculino , Radiografia , Joelho de Quadrúpedes/diagnóstico por imagem , Joelho de Quadrúpedes/lesões , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Ferimentos por Arma de Fogo/cirurgia
10.
J Chromatogr A ; 869(1-2): 129-35, 2000 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-10720231

RESUMO

Reversed-phase packing materials were prepared from HPLC silica and from zirconized HPLC silica support particles having sorbed poly(methyloctylsiloxane) (PMOS) as the stationary phase. Portions of zirconized material were subjected to 80 kGy of ionizing radiation. Columns prepared from these packing materials were subjected to 5000 column volumes each of neutral and alkaline (pH 10) mobile phases, with periodic tests to evaluate chromatographic performance. It was shown that the PMOS stationary phase sorbed onto zirconized silica requires an immobilization treatment (such as gamma irradiation) for long term stability while prior surface zirconization of the silica support surface greatly improves the chromatographic stability of the stationary phase when using alkaline mobile phases.


Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Dióxido de Silício/química , Siloxanas/química , Radiação Ionizante , Silicatos/química , Zircônio/química
11.
J Chromatogr A ; 869(1-2): 137-41, 2000 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-10720232

RESUMO

Effects of high-pH environments on a stationary phase prepared by gamma-radiation immobilization of poly(methyloctylsiloxane) on titanium-grafted silica were investigated by HPLC testing with standard sample mixtures. The HPLC parameters indicate good stationary phase stability to 10000 column volumes each of mobile phases with pH of 7, 9 and 12. At pH 13, the efficiency decreases slowly, although reasonably good separations are still possible until increasing flow resistance no longer allows easy passage of the mobile phase.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Concentração de Íons de Hidrogênio , Dióxido de Silício/química , Siloxanas/química , Titânio/química , Raios gama
12.
Talanta ; 53(2): 453-61, 2000 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18968130

RESUMO

The identities of the species of chromium(VI) that are present in aqueous solution, their spectra and their equilibria, continue to be a subject of discussion in the literature. In this paper, the composition of the Cr(VI) equilibria was estimated from the UV-vis spectra of dilute potassium dichromate solutions, without any prior knowledge of the quantities of pure components, with the aid of Imbrie Q-mode factor analysis (Q-mode FA) followed by Varimax rotation and Imbrie oblique projection. Combining these results with the k-matrix method, it was possible to obtain the spectra of the individual Cr(VI) species. Sets of 3.3x10(-4) and 3.3x10(-5) mol l(-1) Cr(VI) solutions were studied. In the pH range from 1 to 12, two factors were identified, which were related to the two species, chromate ion (CrO(4)(2-)) and bichromate ion (HCrO(4)(-)). When the analysis was extended to concentrated acid media, another factor appeared, which was related to chromic acid (H(2)CrO(4)). No evidence for the dichromate ion (Cr(2)O(7)(2-)) was seen at the Cr(VI) concentrations used. The spectra of the pure components were obtained and pK values for the first and second chromic acid dissociations were estimated as -0.54 and 5.8, respectively.

13.
Scott Med J ; 44(3): 86-8, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10461698

RESUMO

Isaac Israeli (c850-950), philosopher and physician was born in Egypt where he practised as an oculist before moving to Kairouan, in Tunisia, where he served as physician to the Caliph Ziyadat Allah and later to 'Ubayd Allah al-Mahdi. His best known medical work Book of Fevers (Kitab al-Hummayat) was widely used as a medical text until the seventeenth century. This paper reviews Israeli's medical career through his Book of Urine (Kitab al-bawl), based on a fifteenth century Hebrew manuscript Sefer Hasheten (MS Hunter 477) in the Hunterian Collection of the University of Glasgow. This manuscript, most likely a translation from the original Arabic, describes the formation of urine and the value of visual examination of urine for the diagnosis and prognosis of disease. Israeli emerges as an outstanding physician and scholar who made a lasting contribution to Arab-Jewish medicine in its most productive period.


Assuntos
Judeus/história , Manuscritos Médicos como Assunto/história , Medicina Arábica/história , Urologia/história , Egito , História do Século XV , História Antiga , Escócia , Tunísia
14.
J Chromatogr A ; 849(2): 299-307, 1999 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-10457428

RESUMO

Poly(methyloctylsiloxane) (PMOS) was sorbed into the pores of HPLC silica by a solvent evaporation procedure, then irradiated with gamma rays from a cobalt-60 source to absorbed doses in the range from 0 to 200 kGy (1Gy = 1J kg-1). Non-irradiated and irradiated samples were characterized by solvent extraction, specific surface area determination, infrared spectroscopy and reversed-phase column performance. Solvent extraction data reveal that about 40% of the PMOS is not extractable prior to irradiation and this increases to about 75% with radiation doses of 50 kGy or higher. Column performance was improved by the radiation treatment, reaching a maximum efficiency in the dose range of 80-140 kGy while the peak symmetry changed from As = 1.7 to 1.1. The improvement is attributed to the increased mass of polymer immobilized by the radiation treatment and to a more uniform distribution of the immobilized polymer in the silica pore system. A multi-layer stationary-phase model is presented in which the first layer consists of an adsorbed monolayer of PMOS and the second layer is immobilized by gamma radiation.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Dióxido de Silício/química , Raios gama , Modelos Químicos , Oxigênio/química , Radiação , Sílica Gel , Dióxido de Silício/efeitos da radiação , Siloxanas/química , Siloxanas/efeitos da radiação
17.
18.
Proc R Coll Physicians Edinb ; 19(1): 61-8, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11612467
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