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1.
Front Vet Sci ; 11: 1424960, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39076303

RESUMEN

Maternal status during the transition period can significantly impact the health and performance of Holstein dairy calves, with lasting effects on various variables. However, the relationship between maternal late gestation metabolic status, seasonality, and their impact on offspring remains unclear. This study aimed to assess the influence of maternal variables at calving on the performance, metabolism, and immunity of 28 dairy calves during their first month of life. Blood samples were collected from 28 Holstein cows at calving. Median results for maternal variables including non-esterified fatty acids (NEFA), ß-hydroxybutyrate (BHB), glucose, total protein (TP), albumin, triglycerides (TG), total cholesterol (TC), haptoglobin (Hp), body weight (BW), and body condition score (BCS) were determined. These median values served as a basis for categorizing the offspring into two groups based on their dams' high or low degree of each maternal variable. Additionally, calves were categorized by the season of birth (Spring vs. Winter), with 14 in each. Blood samples were collected from the calves at birth and on days 1, 7, 14, and 28 to assess IgG, biochemical parameters, and haptoglobin concentration. Reactive oxygen species (ROS) production by polymorphonuclear cells stimulated by various agents was also evaluated. Clinical assessments were conducted for diarrhea and bovine respiratory disease frequencies. Despite the overall health of the cows, differences were observed in the calves between maternal groups. Heavier cows with high maternal BCS tended to have larger offspring, while high maternal BCS was associated with increased diarrhea prevalence. Low maternal BCS resulted in a stronger innate immune response, indicated by higher ROS production. Calves from cows experiencing metabolic changes during calving displayed elevated Hp concentrations. Spring-born calves were larger but had lower serum IgG concentration and reduced innate immune response compared to winter-born calves. Additionally, spring-born calves exhibited higher Hp and increased diarrhea prevalence on day 28. These findings underscore the importance of the prenatal period in determining neonatal health and suggest further research to elucidate the long-term clinical implications of maternal effects on offspring health and growth. Investigating offspring constituents later in life can provide insight into the persistence of maternal effects over time.

2.
Ciênc. rural (Online) ; 53(5): e20210819, 2023. tab
Artículo en Inglés | LILACS-Express | VETINDEX | ID: biblio-1394273

RESUMEN

ABSTRACT: We evaluated some indicators of innate and humoral immune response in persistently infected (PI) Holstein calves and cows from 1 to 36 months of age matched with controls from the same herd. The effects were cataloged by grouping animals into the following age groups: <12 months, 13 to 24 months, and 25 to 36 months of age. Blood samples were collected once from each animal to measure total serum protein, haptoglobin, and neutralizing antibodies titers induced by respiratory virus vaccination. Total serum protein (g/dL) was lowest in PI calves younger until 24 months old, while haptoglobin concentration was higher in PI cattle. The serum neutralizing titers against BVDV and BRSV were lower in all PI calves and cattle than in controls. PI cattle have a high serum concentration of haptoglobin, and its possible dysregulated innate immune response appears to impact the efficacy of their adaptative immune responses, resulting in poor vaccine responsiveness.


RESUMO: O objetivo desta pesquisa foi avaliar alguns indicadores da resposta imune inata e humoral em bezerros a vacas persistentemente infectadas, entre um a 36 meses de idade, pareados com controles oriundos de um mesmo rebanho. As variáveis respostas foram avaliadas agrupando-se os animais nos seguintes grupos etários: < 12 meses, 13 a 24 meses, 25 a 36 meses de idade. Amostras sanguíneas foram coletadas para mensurar as concentrações séricas de proteína, haptoglobina e anticorpos neutralizantes induzidos pela vacinação contra as viroses respiratórias. Os teores de proteína sérica total (g/dL) foram menores nos animais persistentemente infectados (PI) jovens até 24 meses de idade, enquanto que a concentração de haptoglobina foi maior nos animais PI mais velhos (25 a 36 meses). Os títulos de anticorpos neutralizantes contra o BVDV e BRSV foi menor nos animais PIs independentemente da idade, comparado com o grupo controle. Os valores reduzidos ou nulos de anticorpos contra as viroses respiratórias, combinado com a evidência de resposta imune inata desregulada, contribui com a susceptibilidade dos animais PIs para as infecções secundárias.

3.
Ciênc. rural (Online) ; 53(5): 1-8, 2023. tab
Artículo en Inglés | VETINDEX | ID: biblio-1412894

RESUMEN

We evaluated some indicators of innate and humoral immune response in persistently infected (PI) Holstein calves and cows from 1 to 36 months of age matched with controls from the same herd. The effects were cataloged by grouping animals into the following age groups: <12 months, 13 to 24 months, and 25 to 36 months of age. Blood samples were collected once from each animal to measure total serum protein, haptoglobin, and neutralizing antibodies titers induced by respiratory virus vaccination. Total serum protein (g/dL) was lowest in PI calves younger until 24 months old, while haptoglobin concentration was higher in PI cattle. The serum neutralizing titers against BVDV and BRSV were lower in all PI calves and cattle than in controls. PI cattle have a high serum concentration of haptoglobin, and its possible dysregulated innate immune response appears to impact the efficacy of their adaptative immune responses, resulting in poor vaccine responsiveness.


O objetivo desta pesquisa foi avaliar alguns indicadores da resposta imune inata e humoral em bezerros a vacas persistentemente infectadas, entre um a 36 meses de idade, pareados com controles oriundos de um mesmo rebanho. As variáveis respostas foram avaliadas agrupando-se os animais nos seguintes grupos etários: < 12 meses, 13 a 24 meses, 25 a 36 meses de idade. Amostras sanguíneas foram coletadas para mensurar as concentrações séricas de proteína, haptoglobina e anticorpos neutralizantes induzidos pela vacinação contra as viroses respiratórias. Os teores de proteína sérica total (g/dL) foram menores nos animais persistentemente infectados (PI) jovens até 24 meses de idade, enquanto que a concentração de haptoglobina foi maior nos animais PI mais velhos (25 a 36 meses). Os títulos de anticorpos neutralizantes contra o BVDV e BRSV foi menor nos animais PIs independentemente da idade, comparado com o grupo controle. Os valores reduzidos ou nulos de anticorpos contra as viroses respiratórias, combinado com a evidência de resposta imune inata desregulada, contribui com a susceptibilidade dos animais PIs para as infecções secundárias.


Asunto(s)
Animales , Bovinos , Enfermedades de los Bovinos , Virus de la Diarrea Viral Bovina , Anticuerpos Neutralizantes , Inmunidad
4.
J Dairy Res ; 88(1): 69-72, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33593450

RESUMEN

This research communication presents an automatic method for the counting of somatic cells in buffalo milk, which includes the application of a fuzzy clustering method and image processing techniques (somatic cell count with fuzzy clustering and image processing|, SCCFCI). Somatic cell count (SCC) in milk is the main biomarker for assessing milk quality and it is traditionally performed by exhaustive methods consisting of the visual observation of cells in milk smears through a microscope, which generates uncertainties associated with human interpretation. Unlike other similar works, the proposed method applies the Fuzzy C-Means (FCM) method as a preprocessing step in order to separate the images (objects) of the cells into clusters according to the color intensity. This contributes signficantly to the performance of the subsequent processing steps (thresholding, segmentation and recognition/identification). Two methods of thresholding were evaluated and the Watershed Transform was used for the identification and separation of nearby cells. A detailed statistical analysis of the results showed that the SCCFCI method is able to provide results which are consistent with those obtained by conventional counting. This method therefore represents a viable alternative for quality control in buffalo milk production.


Asunto(s)
Búfalos , Recuento de Células/veterinaria , Procesamiento de Imagen Asistido por Computador/métodos , Mastitis/veterinaria , Leche/citología , Animales , Recuento de Células/métodos , Femenino , Mastitis/patología , Microscopía , Fotograbar
5.
Acta sci. vet. (Impr.) ; 48: Pub.1757-Jan. 30, 2020. tab
Artículo en Inglés | VETINDEX | ID: biblio-1458280

RESUMEN

Background: Newborn calves are born immunosuppressed, hypogammaglobulinemic, immunologically immature, and therefore more vulnerable to many infectious diseases. During pregnancy, the fetal-placental environment is regulated by Th2-type cytokines that neutralize Th1 responses, an important factor for immune defense against viral agents. The ingestion and absorption of colostral immunoglobulins enhance the immunity of the neonate. However, the presence of maternal antibodies might negatively affect the success of parental vaccination in the first two months of life. This study aimed to evaluate the effecacy of parenteral vaccination in newborn calves with high titers of maternal antibodies against respiratory viruses. Materials, Methods & Results: Twenty-eight Holstein calves were allocated to the vaccinated group (VAC, n = 18) or an unvaccinated control group (NVAC, n = 10). The initial vaccination with 5 mL of a commercial vaccine occurred around the 14th day of life (D14) and the booster at D35. Respiratory and diarrhea symptoms were evaluated at D12, D14, D16, D20, D31, D36, D45, D53, and D60. Blood samples were taken for leukogram, haptoglobin, and seroneutralization of BVDV, BoHV-1, BRSV, and BPI3V, at the time of vaccination at D14 (T1), at booster (D35, T2), and 21 days after the booster (D56, T3). Despite the increased prevalence of BRD during the period of the study, no calves from either group exhibited respiratory disease at D12 or D14. In subsequent assessments, the frequency of BRD increased over time in the VAC group until it reached a maximum prevalence of 38.9% (7/18) at D31. In the NVAC group, the maximum prevalence observed was 40% at D45 and D60. A comparison of the frequencies for BRD cases showed a statistical trend at D36 (P = 0.07), with a higher prevalence for the NVAC group (30%) in relation to the VAC group (5.6%). For the NVAC group, a greater number of total...


Asunto(s)
Animales , Recién Nacido , Bovinos , Animales Recién Nacidos/inmunología , Bronconeumonía/inmunología , Bronconeumonía/veterinaria , Complejo Respiratorio Bovino/inmunología , Complejo Respiratorio Bovino/prevención & control , Inmunidad Materno-Adquirida , Calostro
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