Single nucleotide polymorphisms in immunity-related genes and their association with mastitis in Chilean dairy cattle.

Mastitis remains a major cattle disease with great global economic implications. Various approaches are currently employed in attempts to improve understanding of mastitis resistance and develop phenotypic markers for use in breeding programs (e.g., somatic cell score), including QTL discovery, wide-genome association studies, and identification of candidate genes related to immune function. This study evaluated three single nucleotide polymorphisms contained in Toll-like receptor 4 (TLR4) and lactoferrin (LF) genes associated with mastitis traits: TLR4 P-226, TLR4 2021, and LF P-28. Genotyping was performed by restriction fragment length polymorphism-polymerase chain reaction (PCR) and high-resolution melting quantitative PCR from genomic DNA of four dairy cattle breeds (Holstein, Jersey, Montbeliarde, and Overo Colorado) previously classified as healthy, with clinical or with subclinical mastitis. The high-resolution melting quantitative PCR allowed genotyping of each locus and resulted in allele frequencies indicating that all loci were in Hardy-Weinberg equilibrium. The TT genotype of TLR4 2021 was significantly associated with the healthy condition, but no associations with somatic cell score were evident. Further studies are therefore necessary in order to confirm the results of this investigation.

[Characteristics of 86 infants' cluster with A.L.T.E. (Apparent Life-Threatening Event): similarities and differences versus main risk factors for SIDS]. / Caratteristiche di un campione di 86 lattanti A.L.T.E.: analogie e differenze con i principali fattori di rischio per SIDS.

In this study we have gathered 86 ALTE infants' characteristics about physiological, familiar, remote and near pathological case history, modality of apnoea episode's presentation, environmental and behavioural conditions of babies and we have compared these ones with main risk factors for SIDS to find possible similarities or differences. Many of the already known differences or similarities between ALTE and SIDS have been confirmed by our data and new ones have been observed. So we can say that the association between ALTE and SIDS remains contrasting because beside undiscussed factors of association there are other ones which differentiate the two Syndromes.

[Analysis of risk factors for SIDS: experience at a referral center]. / Analisi dei fattori di rischio per SIDS: esperienza in un centro di riferimento.

The aim of this research is to value, with a questionnary for the families, epidemiologic aspects in 20 children died for SIDS. The risk factors we have considered regard: ambiental condition, pregnancy, neonatal and post-neonatal period, and modality of death. The result is that sleeping position, child's age and month in which the death happens, are still the most significant risk factors for SIDS.