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1.
Biopreserv Biobank ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39255193

RESUMO

The peroxidation of spermatozoa membrane phospholipids is a primary cause of irreversible changes in the preservation of avian semen. To address this issue, the objective of the present study was to assess the potential of Urtica dioica extracts in protecting avian spermatozoa during prolonged storage. Gas chromatography-mass spectroscopic techniques were employed to evaluate the bioactive compounds present in the aqueous and ethanolic extracts obtained from the aerial parts and roots of U. dioica. Semen samples were collected from 16 roosters twice a week and were diluted in Lake's extender containing different concentrations (0, 0.5, and 1 mg/100 mL) of the various extracts. Subsequently, the extended semen samples were cooled and stored at 5°C, and the sperm quality parameters were assessed at 0, 12, 24, and 36 hours of storage. The data from this experiment clearly demonstrate that the addition of nettle root aqueous extracts to the semen diluent, especially at a concentration of 0.5 mg/100 mL, resulted in a significant improvement in various sperm quality parameters. Notably, there were enhancements in total and progressive sperm motilities, viability, fertility, membrane integrity, acrosomal membrane integrity, and a reduction in malondialdehyde production in rooster semen stored in vitro for up to 36 hours. Interestingly, the present study reveals that the beneficial effects of the aqueous extracts from different parts of the nettle were supported not only by the conventional manual method but also by the computer-assisted sperm analysis system. This dual confirmation further emphasizes the positive impact of the aqueous extract on various sperm traits during cooled semen preservation. In conclusion, this study highlights the potential of U. dioica extracts, particularly the aqueous extract from nettle roots at a concentration of 0.5 mg/100 mL, in safeguarding avian spermatozoa during prolonged storage. The significant improvements in various sperm quality parameters and the validation of results through both manual and computer-assisted analysis methods provide strong evidence for the application of U. dioica extracts in avian breeding programs and artificial insemination practices.

2.
Biopreserv Biobank ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39166325

RESUMO

The purpose of this study, carried out in two experiments, was to investigate the antioxidant effect of Prosopis farcta in Experiment 1, and trehalose in Experiment 2 in the freezing extender, on the quality of frozen-thawed goat epididymal spermatozoa. Sperm samples were added to based egg-yolk Tris-extender containing experimental treatments. The first experimental treatments included the following: an extender of the control group without additive and extender containing 50, 100, or 150 µg/mL of Prosopis farcta ethanolic extract (PEE1, PEE2, and PEE3, respectively). Treatments of the second experiment include an extender of the control group without additive, an extender containing 100 mM of trehalose (Tr), an extender containing 100 µg/mL PEE2, and 100 µg/mL PEE2 + 100 mM Tr. The results of the first experiment showed that PEE2 compared with the control group led to a significant decrease (p < 0.05) in malondialdehyde (MDA) concentration. Also, PEE1 and PEE2 treatments resulted in a significant increase (p < 0.05) in motility parameters by computer-assisted sperm analysis, and MDA concentrations decreased significantly (p < 0.05) in all treatments compared with the control group. In general, the results of the present experiment showed that Prosopis farcta ethanolic extract at the level of 100 µg/mL was effective in improving the quality of frozen-thawed goat epididymal spermatozoa. Also, a combination of Prosopis farcta ethanolic extract and trehalose can be successful in freezing goat epididymal spermatozoa.

3.
Theriogenology ; 212: 73-82, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37708817

RESUMO

Epididymal lithiasis, characterized by the formation of stones in the epididymis, has been associated with a decline in fertility in roosters. This study aimed to investigate the reproductive performance, ultrastructural characteristics, and expression of aromatase cytochrome P450 (CYP19) and aquaporin 9 (AQP9) in aged broiler breeder roosters affected by epididymal lithiasis. X-ray analysis confirmed the presence of genital stones in both the epididymis and testicular tissue regions. While there was a significant decrease in sperm concentration in the affected roosters compared to non-affected roosters, no significant differences were observed in total and progressive sperm motility between the two groups. Furthermore, the affected roosters exhibited significant abnormalities in semen parameters, except for sperm concentration and morphology. Transmission electron microscopy (TEM) revealed the depletion and deciliation of ciliated cells in the distal efferent ductules of the epididymis in affected roosters. Additionally, the expression of CYP19 and AQP9 was found to be increased in the epididymal region of affected roosters. Notably, we report the presence of testicular stones for the first time in this study, in addition to epididymal stones. Considering the male reproductive tract lesions observed, we propose the term "genital stones" to describe these conditions. Moreover, our findings suggest that the overexpression of AQP9, which is associated with a high copy number of the CYP19 gene in the epididymal region of affected aged roosters, may contribute to the formation of genital stones by promoting increased reabsorption of fluids in the epididymis. The condensation of epididymal duct contents and reduction in the population of ciliated cells further impairs semen movement and can lead to the blockage of extra-testicular ducts, resulting in the low fertility syndrome observed in aged roosters.

4.
ACS Biomater Sci Eng ; 9(9): 5279-5292, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37606622

RESUMO

Due to the presence of various autofluorescent compounds in biological samples like serum and the photobleaching of organic fluorophores, fluorescence sensing has limited practical applicability. This study describes the development of an improved ratiometric fluorescence assay to determine the nucleocapsid protein (N protein), one of the most conserved biomarkers of Covid-19 in spiked and serum samples using highly stable buffer-based near IR-dual emission carbon dots (CDs) encapsulated into the cavities of cleavable silica nanocapsule (SNCs) nanocomposite. The cavities of cleavable silica nanocapsules (SNCs) and the formed core-shell CDs@ SNCs were used as a superior reservoir of fluorescent markers produced by cohydrolyzing tetraethyl orthosilicate and diiminosilane linker, which held hundreds of CDs in silica shell frameworks. The SiO2 nanocomposite was modified with an N protein antibody that specifically paired to the receptor binding region of the Cov-19 spike protein subunit. CDs were taken out of SNCs by NaBH4 reduction, and the released CDs exhibited dual emission at 475 and 675 nm when excited at 400 nm. Ratiometric detection is completed over a binding-induced, concentration-dependent immuno-affinity of the N protein that drives the fluorescence quenching phenomenon between the CDs as fluorophore and the AuNPs as quencher. As the N protein concentration increased, the intensity of the red emission (675 nm) dropped, whereas the intensity of the green emission (475 nm) already remained constant, which is due to sandwich immunoassays of CDs around AuNPs. Using the exceptional fluorescent characteristics of CDs and the high selectivity of nanocomposite functionalized with N-protein antibody, the developed assay efficiently eliminates the autofluorescence background interference of serum samples. The fluorescence ratio (I475/I675) provides a limit of detection of 2 pg mL-1 over a linear range of 0.01 to 5 ng mL-1 and exhibits an amplified sensitivity of 54 times compared to conventional immunoassay using CDs as fluorescent labels. With one-step signal amplification and requiring small sample quantities (only 20 µL), this sensing platform can be effectively used for the accurate detection of N protein, and no cross-reactivity is detected in the presence of different interfering agents.


Assuntos
COVID-19 , Nanopartículas Metálicas , Humanos , Proteínas do Nucleocapsídeo , Dióxido de Silício , Ouro , COVID-19/diagnóstico , Bioensaio , Carbono
5.
Reprod Domest Anim ; 57(7): 806-812, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35352399

RESUMO

Aromatase, a member of the cytochrome P450 superfamily (encoded by CYP19), is the enzyme responsible for the aromatization of androgens into estrogens which is the last step of estrogen biosynthesis. It plays an important role in reproduction and sexual development. The aromatase expression in many tissues and organs of different species is shown in the last two decades' investigation. This study was conducted to determine the relative seasonal expression of aromatase mRNA in testis, epididymis, vas deferens, prostate and seminal vesicle of a male goat. The aromatase expression of 16 male goat reproductive organs, slaughtered in the different seasons (n = 4 each season), were determined by quantitative real-time polymerase chain reaction (qRT-PCR). Results showed that during the autumn, aromatase mRNA expression of the testis was found to be significantly higher (p < .05) as compared to the spring and summer seasons. Higher aromatase mRNA expression was also found in the epididymis and seminal vesicle organs during the autumn and summer seasons. Interestingly, prostate and vas deferens aromatase mRNA expression during the summer was higher than in other seasons. The aromatase mRNA level analysis revealed that aromatase is expressed in all the examined reproductive organs in which a strong expression signal was detected in the testis and epididymis tissues. This study shows the expression of the aromatase in the goat reproductive organs in the breeding season which resembles other mammals with continuous breeding.


Assuntos
Aromatase , Regulação Enzimológica da Expressão Gênica , Genitália Masculina , Cabras , Estações do Ano , Animais , Aromatase/genética , Aromatase/metabolismo , Perfilação da Expressão Gênica , Genitália Masculina/enzimologia , Cabras/genética , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
6.
Anim Biosci ; 35(11): 1666-1674, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34530513

RESUMO

OBJECTIVE: Letrozole, a potent aromatase inhibitor, is known to have the potential to modify male reproductive function by altering sex hormone levels. This study aimed to evaluate the semen and testicular characteristics and hormonal profile of aged Mrakhoz bucks (Capra hircus) treated with letrozole. METHODS: Twelve Markhoz male goats, aged between 4.5 to 5.5 years with an average body weight (BW) of 61.05±4.97 kg were used for the study. Animals were randomly divided into two equal groups and subcutaneously received either 0.25 mg/kg BW of letrozole or a control every week for 2 months. The semen collections were performed every 10 days, and blood samples and testicular biometric records were collected at 20 days intervals. RESULTS: Letrozole causes increased testosterone and follicle-stimulating hormone levels, testosterone to estradiol ratio, semen index and reaction time during the period from 20th to 60th days (p<0.05). Furthermore, letrozole-treated bucks had higher semen volume, sperm concentration, and total sperm per ejaculate from 30th to 60th days (p<0.05). However, no differences occurred between the groups in scrotal circumference, relative testicular volume, semen pH, abnormality, acrosome integrity, and membrane integrity of sperm during the study (p>0.05). The serum luteinizing hormone levels, sperm viability, motility, and progressive motility increased, and estradiol levels decreased after 40th to 60th days of letrozole treatment (p<0.05). CONCLUSION: Letrozole application to aged Markhoz bucks provokes reproductive hormonal axis which, in turn, induces enhancement of semen production and quality.

7.
Reprod Domest Anim ; 55(10): 1303-1313, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32654314

RESUMO

This study investigated the effect of pentoxifylline (PTX) and Basal Medium Eagle (BME) on frozen-thawed goat spermatozoa. Immediately after initial examination of ejaculated semen, samples were pooled and reexamined for quality. Then, samples were divided into eight equal aliquots and diluted with a basic tris-extender containing PTX (3, 6, 9 mM) and BME (5 mM) to reach a final concentration of 25 × 109 and frozen. After 24 hr, the samples were individually thawed at 37°C for 30 s and evaluated for different characteristics. Obtained post-thaw results from Computer-Assisted Sperm Analysis indicate using of 3 and 6 mM PTX led significantly to an improvement in total motility, progressive motility and velocity characteristics of spermatozoa, except the beat/cross frequency (BCF) which indicated statistically no differences (p > .05) among control and treatments. Diluents prepared with BME (5 mM) and PTX alone (3 and 6 mM) improved significantly the membrane integrity-functionality, acrosome integrity and also hyaluronidase activity. Regarding recovery rate, the results showed significantly (p < .05) higher values for diluents containing 3 and 6 mM PTX compared to other groups. Malondialdehyde concentration exhibited also a significant difference (p < .05) in diluents supplemented with 5 mM BME, 3, 6 and 9 mM PTX, and mixture of 3 mM PTX and 5 mM BME which illustrate a similarity for active mitochondria, apoptotic-like and dead spermatozoa. Finally, the ratio of sperm chromatin dispersion stained spermatozoa presented significant differences (p < .05) among treatments in which the diluents added PTX alone demonstrated significantly lower values than control and extenders containing the mixtures of BME and PTX. In conclusion, the observation in this study indicates using of 3 and 6 mM PTX and BME alone may improve significantly (p < .05) the quality of cryopreserved goat spermatozoa.


Assuntos
Criopreservação/veterinária , Pentoxifilina/farmacologia , Preservação do Sêmen/veterinária , Animais , Criopreservação/métodos , Crioprotetores/farmacologia , Cabras , Masculino , Análise do Sêmen/veterinária , Preservação do Sêmen/métodos , Espermatozoides/efeitos dos fármacos
8.
Theriogenology ; 147: 183-191, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31785859

RESUMO

This study evaluated the growth performance, testicular and semen characteristics, and hormonal profile of Markhoz (Iranian Angora) bucklings injected with letrozole (LTZ). Twenty-eight 4-4.5 month old bucks were randomly assigned into four groups and received either 0.25 mg/kg body weight (BW) LTZ subcutaneously (sc LTZ) or intramuscularly (im LTZ), and also sc (sc CONT) or im (im CONT) controls every week for 3 months. The study was performed at the beginning of the breeding season in Sanandaj Animal Husbandry Research Station (46.99 °E, 35.31 °N). The results showed that LTZ causes increased final body weight (25.78 ± 1.61 kg), higher average daily gain (104 ± 0.03 g/days), and decreased feed conversion ratio (7.81 ± 2.57) (P < 0.05). The pre-slaughter, hot, and cold carcass weights (27.56 ± 2.40, 11.45 ± 1.07 and 11.11 ± 1.05 kg, respectively) were (P < 0.05) heavier in LTZ groups while other carcass characteristics did not differ between groups. No differences occurred between the groups in biochemical parameters, except high-density lipoprotein levels (35.47 ± 2.43 mg/dL) which was higher in LTZ treatments (P < 0.05). LTZ-treated bucks had larger scrotal circumference (20.12 ± 5.75 cm), higher relative testicular weight (560.91 ± 78.59 mg/100 g BW) and volume (175.5 ± 29.71 cm3), greater diameter of seminiferous tubules (224.5 ± 5.21 µm), and number of Sertoli cells (8.39 ± 0.77) (P < 0.05). Semen volume (0.74 ± 0.16 mL), sperm concentration (2.64 ± 0.19 × 10-9/mL), total sperm per ejaculate (1.95 ± 0.49 × 10-9), and semen index (1248 ± 323) increased (P < 0.05) by LTZ treatments, while semen pH (6.77), motility (80.91%), progressive motility (76.75%), viability (83.35%), abnormality (13.70%), acrosome integrity (78.06%), and membrane integrity (80.05%) of sperm remained unaffected. Intratesticular and serum testosterone (T) levels (7.97 ± 0.89 ng/mg protein and 2.47 ± 0.59 ng/mL, respectively), serum luteinizing hormone (LH), growth hormone (GH) levels (1.71 ± 0.24 and 3.62 ± 0.33 ng/mL, respectively) of LTZ groups were elevated, whereas intratesticular and serum estradiol (E2) levels (84.14 ± 8.15 pg/mg protein and 32.33 ± 2.16 pg/mL, respectively) decreased (P < 0.05). No differences were recorded between the sc and im routes of LTZ administration in the measured parameters. To conclude, we have found that LTZ treatment improves growth and reproductive functions of goat bucklings associated with increased serum LH and GH, elevated T and reduced E2 levels in both serum and testis.


Assuntos
Inibidores da Aromatase/farmacologia , Fertilidade/efeitos dos fármacos , Cabras/crescimento & desenvolvimento , Letrozol/farmacologia , Testículo/efeitos dos fármacos , Animais , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Cabras/sangue , Hormônio do Crescimento/sangue , Hormônio Luteinizante/sangue , Masculino , Tamanho do Órgão , Testículo/anatomia & histologia , Testosterona/sangue , Aumento de Peso
9.
Biol Trace Elem Res ; 185(2): 475-485, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29450680

RESUMO

Silver nanoparticles (AgNPs) have recently emerged as a powerful agents for disinfection in the poultry industry. AgNPs are capable of epithelial barriers passing from the route of exposure to the vital organs and cells. This study evaluated the effects of AgNPs on organs weights, blood biochemical, hematological, and coagulation parameters, antioxidant enzyme activities, and histopathological changes and silver concentrations of liver and kidney tissues in laying Japanese quails after exposure to the nanoparticles. The layer quails were randomly assigned to 4 groups, consisting of six replicates, three quails each. The treatments included 0, 4, 8, and 12 mg/L of AgNPs in daily drinking water for 30 weeks. AgNPs decreased the relative weight of liver, ileum and large intestine (P < 0.05). Administration of AgNPs elevated plasma fibrinogen while decreased serum aspartate aminotransferase activity (P < 0.05). The antioxidant status of the liver showed that malondialdehyde level, an end product of lipid peroxidation, was higher (P < 0.05) and catalase activity was lower (P < 0.05) in the quails exposed to AgNPs. The accumulation of silver in the liver and kidney tissues were increased in a dose-dependent manner after exposure to AgNPs (P < 0.05). Histopathological findings showed reduced lipid vacuolization of hepatocytes in the 12 mg/L AgNPs treatment. In conclusion, the results indicated that AgNPs administration to drinking water can lead to oxidative stress and liver damage in laying quails which may be a predisposing for liver dysfunction.


Assuntos
Rim/efeitos dos fármacos , Hepatopatias/patologia , Fígado/efeitos dos fármacos , Nanopartículas Metálicas/química , Oviposição , Estresse Oxidativo/efeitos dos fármacos , Prata/farmacologia , Administração Oral , Animais , Coturnix , Feminino , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Fígado/patologia , Hepatopatias/metabolismo , Nanopartículas Metálicas/administração & dosagem , Distribuição Aleatória , Prata/administração & dosagem , Prata/sangue , Prata/farmacocinética , Distribuição Tecidual
10.
Anal Biochem ; 466: 89-97, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25172129

RESUMO

Here, we describe the fabrication of an electrochemical immunoglobulin E (IgE) aptasensor using enzyme-linked aptamer in the sandwich assay method and thionine as redox probe. In this protocol, 5'-amine-terminated IgE aptamer and thionine were covalently attached on glassy carbon electrode modified with carbon nanotubes/ionic liquid/chitosan nanocomposite. Furthermore, another IgE aptamer was modified with biotin and enzyme horseradish peroxidase (HRP), which attached to the aptamer via biotin-streptavidin interaction. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry were performed at each stage of the chemical modification process to confirm the resulting surface changes. The presence of IgE induces the formation of a double aptamer sandwich structure on the electrode, and the electrocatalytic reduction current of thionine in the presence of hydrogen peroxide was measured as the sensor response. Under optimized conditions and using differential pulse voltammetry as the measuring technique, the proposed aptasensor showed a low detection limit (6 pM) and high sensitivity (1.88 µA nM(-1)). This aptasensor also exhibited good stability and high selectivity for IgE detection without an interfering effect of some other proteins such as bovine serum albumin (BSA) and lysozyme. The application of the aptasensor for IgE detection in human serum sample was also investigated. The proposed protocol is quite promising as an alternative sandwich approach for various protein assays.


Assuntos
Aptâmeros de Nucleotídeos/química , Bioensaio/métodos , Técnicas Eletroquímicas , Imunoglobulina E/análise , Animais , Bovinos , Peroxidase do Rábano Silvestre/metabolismo , Humanos , Imunoglobulina E/química , Limite de Detecção , Microscopia Eletrônica de Varredura , Mieloma Múltiplo/diagnóstico , Soroalbumina Bovina/química
11.
Avian Pathol ; 42(2): 88-99, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23581435

RESUMO

The use of attenuated vaccines or the occurrence of low virulent T-lymphotropic or B-lymphotropic viruses in flocks may alter the immune responses of young chicks in spite of the absence of clinical signs. Infections with a low virulent T-lymphotropic chicken infectious anaemia virus (lvCIAV) followed by infection with an intermediate B-lymphotropic infectious bursal disease virus (iIBDV) were conducted in specific pathogen free chicks. Thirty-six 1-day-old chicks were infected with the lvCIAV strain (CAV-VAC®) and a similar number of chicks were inoculated with phosphate-buffered saline. At 14 days after lvCIAV infection, one group of 18 lvCIAV-infected chicks and one group of 18 uninfected chicks were infected with an iIBDV strain. At 4, 7 and 14 days post infection with iIBDV, six chicks from each group were euthanized and lymphoid organs were collected. Detection of lvCIAV and iIBDV genomes was conducted by polymerase chain reaction and reverse transcriptase-polymerase chain reaction, respectively. Double-labelled lymphoid subsets from the thymus, spleen and bursa were studied by cytofluorometric analysis. The results reveal that previous infection with lvCIAV increases the occurrence of the lvCIAV and iIBDV genome in thymus and/or bursa without the occurrence of clinical signs in dually lvCIAV/iIBDV-infected chicks. However, the decreases of B cells in spleen and bursa and increases of T-cell subsets in bursa observed in chicks infected with iIBDV did not occur in chicks previously infected with lvCIAV. Taken together, these results suggest that previous infection of young chicks with lvCIAV decreases lymphoid disorders induced by iIBDV while subsequent iIBDV infection increases the lvCIAV genome in lymphoid organs.


Assuntos
Infecções por Birnaviridae/veterinária , Vírus da Anemia da Galinha , Galinhas , Infecções por Circoviridae/veterinária , Coinfecção/veterinária , Vírus da Doença Infecciosa da Bursa , Doenças das Aves Domésticas/virologia , Análise de Variância , Animais , Linfócitos B/imunologia , Bolsa de Fabricius/virologia , Coinfecção/virologia , Primers do DNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/imunologia , Timo/virologia
12.
Avian Pathol ; 40(4): 377-85, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21812717

RESUMO

The chicken infectious anaemia virus (CIAV) infection may induce immunosuppression and persistent infection. The use of vaccination in young chicks is still controversial due to its low immune efficiency. In order to verify the viral persistency of a vaccinal strain of CIAV and its associated-lymphoid cell disorders, 54 1-day-old specific pathogen free chicks were vaccinated (CIAV-VAC(®); Intervet, Millsboro, Delaware, USA) and haematologic examination, expression of viral VP3 gene, humoral response and phenotyping of lymphoid cells were studied in lymphoid organs at various times post vaccination (p.v.). No clinical signs were observed but light heteropaenia was detected in CIAV-vaccinated chicks. The VP3 gene of CIAV was detected by polymerase chain reaction in the thymus and spleen from day 7 until 28 days p.v. Thymic larger CD4(+)CD8(+) cells increased only at 7 days p.v. while smaller CD4(+)CD8(+) cells decreased after 14 and 28 days in CIAV-vaccinated birds. The CD4 expression, in contrast to that seen for CD8, decreased in thymocytes from the CIAV-vaccinated group. In the spleen and bursa, the percentage of CD8(+) cells increased at 7 and 28 days p.v. only, while CD4(+) cells decreased simultaneously. The vaccinated chicks also exhibited a higher number of splenic CD3(-)CD8(+) cells (natural killer cells). The anti-CIAV antibody responses, however, remained low in most vaccinated chicks and did not persist up to 18 days p.v. These results suggest that the vaccinal virus strain is clinically attenuated but persists in the thymus and spleen in some birds, inducing a low humoral immune response and altering thymopoiesis.


Assuntos
Vírus da Anemia da Galinha/imunologia , Galinhas/imunologia , Linfócitos/patologia , Doenças das Aves Domésticas/imunologia , Baço/virologia , Timo/virologia , Animais , Embrião de Galinha , Vírus da Anemia da Galinha/genética , Delaware , Imunidade Humoral/imunologia , Terapia de Imunossupressão/veterinária , Linfócitos/imunologia , Linfócitos/virologia , Fenótipo , Doenças das Aves Domésticas/patologia , Doenças das Aves Domésticas/virologia , Organismos Livres de Patógenos Específicos , Timócitos/virologia , Fatores de Tempo , Vacinação/efeitos adversos , Vacinação/veterinária , Vacinas Atenuadas/efeitos adversos , Vacinas Virais/efeitos adversos
13.
Avian Dis ; 51(4): 918-23, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18251403

RESUMO

Growth rate in broiler birds has increased substantially in the last decade due to improvement in genetics, feed formulation, cleaner environment, and vaccine formulations. As a result, it has become necessary to review and revise prediction method for vaccination in chicks. This study was undertaken to determine the possible use of the rate of weight gain rather than age in predicting vaccination time. Two groups of 1-day-old broilers originating from old and young breeders, respectively, and with different levels of maternal antibodies against infectious bursal disease virus (IBDV) were used in this study. The chicks were divided into four groups and subjected to two feed regiments: groups A1 and B1 were fed broiler feed for normal growth rate, and groups A2 and B2 were fed breeder feed for slower growth rate. At 1, 4, 8, 12, 16, 22, 29, and 36 days of age, 22 chicks in each group were weighed, and blood samples were collected. Serum samples were tested for antibodies against IBDV by enzyme-linked immunosorbent assay (ELISA) and virus neutralization test. Maternal antibody decline curves for each group were plotted according to chick age and chick weight. Fast-growing birds in groups A1 and B1 showed a faster rate of antibody decline, whereas slow-growing birds in groups A2 and B2 had a slower rate of antibody decline. Based on the effect of weight gain on maternal antibody decline, a new way of predicting vaccination time for IBDV based on measuring maternal antibody titers at 4 days of age was proposed and tested. The predicted antibody decline was shown to correspond to the real ELISA titers measured in our experiments (R = 0.9889), whereas a lower correlation (R = 0.8355) was detected between real ELISA titers and the titers predicted by the current method using age-based Deventer formula.


Assuntos
Infecções por Birnaviridae/veterinária , Peso Corporal , Galinhas , Vírus da Doença Infecciosa da Bursa/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinação/veterinária , Vacinas Virais/imunologia , Animais , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/prevenção & controle , Esquema de Medicação , Ensaio de Imunoadsorção Enzimática , Masculino , Doenças das Aves Domésticas/imunologia , Fatores de Tempo , Vacinas Virais/administração & dosagem
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