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Genetic uniqueness of Cryptosporidium parvum from dairy calves in Colombia

Avendaño, Catalina; Ramo, Ana; Vergara Castiblanco, Claudia; Sánchez Acedo, Caridad; Quílez, Joaquín (2018)

Fecal specimens from 432 pre-weaned calves younger than 35 days were collected over a 2-year period (2010–2012) from 74 dairy cattle farms in the central area of Colombia. These samples were microscopically examined for ...
Glycerol: Dietary supplement and response in dairy cattle

Nivia Osuna, Alexander; Ramírez Peña, Alejandra; Porras Sánchez, Claudia Jineth; Marentes Barrantes, Diana Lorena (2020)

821 Glicerol: suplemento alimenticio y su respuesta en bovinos de leche1Glycerol: dietary supplement and response in dairy cattleAlexander Nivia-Osuna2, Alejandra Ramírez-Peña2, Claudia Jineth Porras-Sánchez2, ...
Multilocus fragment analysis of Cryptosporidium parvum from pre-weaned calves in Colombia

Avendaño, Catalina; Ramo, Ana; Vergara Castiblanco, Claudia; Monteagudo, Luis V.; Sánchez Acedo, Caridad; Quílez, Joaquín (2019)

The intra-species genetic diversity of Cryptosporidium parvum in dairy cattle farms in the central area of Colombia was investigated using a multilocus fragment typing approach with nine variable-number tandem-repeat (VNTR) ...

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Genetic uniqueness of Cryptosporidium parvum from dairy calves in Colombia
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Avendaño, Catalina | 2018

Fecal specimens from 432 pre-weaned calves younger than 35 days were collected over a 2-year period (2010–2012) from 74 dairy cattle farms in the central area of Colombia. These samples were microscopically examined for the presence of Cryptosporidium oocysts, and positive specimens were selected for molecular examination. Microscopy revealed that 115 calves (26.6%) from 44 farms (59.5%) tested positive. Oocyst shedding was recorded in calves aged 3-day-old onwards, although the infection rate peaked at 8–14 days (40.7%). Infection rates were higher in diarrheic (52.2%) than in non-diarrheic calves (19.9%) (p < 0.0001, χ2), and infected calves had up to seven times more probability of having diarrhea than non-infected calves. Cryptosporidium species and subtypes were successfully identified in 73 samples from 32 farms. Restriction and sequence analyses of the SSU rRNA gene revealed C. parvum in all but two isolates identified as Cryptosporidium bovis. Sequence analyses of the 60-KDa glycoprotein (gp60) gene revealed eight subtypes within the IIa family. An unusual subtype (IIaA18G5R1) was the most prevalent and widely distributed (more than 66% specimens and 68% farms) while the subtype most frequently reported in cattle worldwide (IIaA15G2R1) was found in less than 13% of specimens and 16% farms. The remaining subtypes (IIaA16G2R1, IIaA17G4R1, IIaA20G5R1, IIaA19G6R1, IIaA20G6R1, and IIaA20G7R1) were restricted to 1–3 farms. This is the first large-sample size study of Cryptosporidium species and subtypes in Colombia and demonstrates the genetic uniqueness of this protozoan in cattle farms in this geographical area.

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Glycerol: Dietary supplement and response in dairy cattle
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Nivia Osuna, Alexander | 2020

821 Glicerol: suplemento alimenticio y su respuesta en bovinos de leche1Glycerol: dietary supplement and response in dairy cattleAlexander Nivia-Osuna2, Alejandra Ramírez-Peña2, Claudia Jineth Porras-Sánchez2, Diana Lorena Marentes-Barrantes3© 2020 Agronomía Mesoamericana es desarrollada en la Universidad de Costa Rica bajo una licencia Creative Commons Atribución-NoComercial-SinDerivar 4.0 Internacional. Para más información escriba a pccmca@ucr.ac.cr o pccmca@gmail.comResumenIntroducción. Las tecnologías de producción animal han permitido la utilización eficiente de recursos alimenticios para satisfacer las necesidades nutricionales y generar alimento para la población humana. Fuentes alternativas de alimentación en rumiantes han sido utilizadas para el incremento de los indicadores productivos y reproductivos. La expansión del área sembrada con palma de aceite (Elaeis guineensis) destinada a la producción de biodiesel como fuente de energía renovable, ha favorecido el desarrollo de procesos agroindustriales mediante la generación de subproductos, como el glicerol, que por su efecto glucogénico, podría ser considerado como fuente energética alternativa. Objetivo. Fundamentar el efecto nutricional del glicerol como suplemento alimenticio sobre la respuesta en bovinos de leche. Desarrollo. Estudios han reportado efectos benéficos del uso de glicerol como terapia en la prevención de trastornos metabólicos asociados al período de transición, caracterizado por deficiencias y desequilibrios nutricionales. Diversos resultados han mostrado que su respuesta está asociada con el nivel de inclusión (5 a 12 % MS) en la dieta y la tasa de desaparición a nivel ruminal, que incide sobre la ingesta. Su composición varía de acuerdo con la calidad de la materia prima (grado de impurezas), lo que podría considerarse como inseguro para su suministro. Las fuentes energéticas han mostrado un efecto favorable sobre la respuesta reproductiva expresada por el incremento de la tasa de ovulación, el mejoramiento en la modulación de la síntesis de prostaglandina uterina, mejor calidad de los ovocitos, mayor competencia en el desarrollo embrionario e incremento en las tasas de concepción en las que el uso de glicerol podría ser asociado. Conclusión. El glicerol podría ser considerado como ingrediente esencial en dietas alimenticias por su alto valor energético y efecto benéfico sobre los indicadores productivos y reproductivos, sin embargo, es necesario ampliar su estudio.

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Multilocus fragment analysis of Cryptosporidium parvum from pre-weaned calves in Colombia
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Avendaño, Catalina | 2019

The intra-species genetic diversity of Cryptosporidium parvum in dairy cattle farms in the central area of Colombia was investigated using a multilocus fragment typing approach with nine variable-number tandem-repeat (VNTR) loci and the gp60 gene. Genomic DNA of 70 C. parvum isolates from pre-weaned calves in 32 farms was analysed. Most markers showed two (ML1, MSB, CP47, and MSC6-7) or three alleles (5B12, Cgd2_3850, and Cgd6_5400), although they exhibited a major allele accounting for more than 69% of specimens, which explains their low discriminatory index. The TP14 microsatellite was monomorphic while a total of six alleles were found at the ML2 microsatellite. The two novel allelic variants (219bp, 245bp) exhibited by more than 36% of specimens at the latter locus were a remarkable finding. The 10-markers typing tool provided a Hunter-Gaston discriminatory value of 0.940 (95% CI, 0.918 – 0.961) and differentiated 22 multilocus subtypes (MLTs). Nevertheless, the combination of the three most informative markers (ML2, gp60, and Cgd2_3850) differentiated 68% of MLTs and hardly impaired the discriminatory index. The fact that many MLTs (13/22) were distinctive for individual farms provides evidence for the endemic nature of the infection and the major role played by transmission within farms. The eBURST algorithm suggested a low degree of genetic divergence. All but three MLTs were clustered in a clonal complex with a star-like topology typical of clonal expansion, however linkage analysis did not find evidence of linkage disequilibrium. Bayesian analysis also identified a genetic structure with K = 3 being the best estimation of ancestral clusters, although a large proportion of isolates (35%) could not be allocated to a single population, which indicates their mixed origin. The results confirm the genetic distinctiveness of C. parvum in cattle farms in this geographical area. This is the first multilocus analysis on the intra-specific variability of Cryptosporidium from calves in South America.

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