Expression of genes associated with fertility in the uterus and oviduct of heifers challenged with lipopolysaccharide.

Lipopolysaccharide (LPS) endotoxemia has been negatively associated with fertility. This study aimed to investigate the effect of LPS-induced inflammation on gene expression associated with bovine fertility in the uterus and oviduct. Sixteen healthy heifers were divided into two groups. The LPS group (n = 8) received two intravenous (i.v.) injections of 0.5 µg/kg of body weight of LPS with a 24-h interval, and the control group (n = 8) received two i.v. injections of saline solution with the same interval of time. All the animals had the follicular wave synchronized. Three days after the second injection of LPS, all animals were slaughtered and uterine and oviduct samples were collected. Gene expression associated with inflammatory response, thermal and oxidative stresses, oviduct environment quality, and uterine environment quality was evaluated. Body temperature and leucogram demonstrated that LPS induced an acute systemic inflammatory response. In the uterus, the expression of PTGS2 and NANOG genes was downregulated by the LPS challenge. However, no change in expression was observed in the other evaluated genes in the uterus, nor those evaluated in the oviduct. In conclusion, the inflammatory process triggered by LPS did not persist in the uterus and oviduct 3 days after challenge with LPS. Nonetheless, reduction in PTGS2 and NANOG expression in the uterus suggested that, indirectly, LPS may have a prolonged effect, which may affect corpus luteum and endometrial functions.

Macroscopic and Histological Morphology of the Equine Digital Cushion and Its Association with Subcutaneous Fat Thickness.

This study evaluated the influence of the Body Condition Score (BCS) and subcutaneous fat thickness on the tissue composition of the digital cushion in horses. Sixty mixed breeds of Criollo horses (21 males and 39 females) were sent for slaughter. All animals were submitted to BCS analysis, through visual antemortem evaluation, and then ultrasound evaluation to estimate the subcutaneous fat thickness. Macroscopic analyses of the thoracic and a pelvic limb (weight, volume, and density of the hooves and digital cushions) were performed. In addition, measurements of the area of internal structures to the hoof and histological analyzes were carried out to measure the areas of adipose, fibroelastic, and collagen fibers of the digital cushion. There were no macroscopic differences in the digital cushion between thoracic and pelvic limbs or between genders (P > .05). Likewise, the histological characteristics between the limbs and the genders were similar (P > .05). There was no correlation between the weight, volume, and density of the digital cushion with the BCS (P > .05). A positive correlation was observed with the area of adipose tissue (P = .038, R2 = 0.28) and a negative correlation with area of fibroelastic tissue (P = .005, R2 = -0.37) and collagen fibers (P = .003, R2 = -0.39). In conclusion, the adipose tissue, fibroelastic tissue, and collagen fibers of equine digital cushion alter their areas in the functions of the various subcutaneous fat patterns in horses.

Impact of high-energy diets on the rumen environment and digital cushion in confined cattle / O impacto de dietas de alto valor energético sobre o ambiente ruminal e o tecido digital em bovinos confinados

This study aimed to identify gross and microscopic changes, caused by high-energy diets, in the rumen environment and hoof of confined beef cattle. The study sample comprised 40 confined heifers (Bos taurus) with no disease history divided into four experimental groups using different diets: Group 1 (D1, control), 48:52 forage:concentrate ratio; Group 2 (D2), 30:70 forage:concentrate ratio; Group 3 (D3), 30:70 forage:concentrate ratio + sucrose; Group 4 (D4), 100% concentrate. All animals underwent clinical examination, assessment of ruminal fluid pH and lameness, and sample collection after slaughter for histopathology of the hoof laminae and digital cushion and ruminal tissue. All dependent variables of the study were compared using the SPSS 20.0 statistical software. The variables that did not show normality (HR, RM, ST, and CRT) were compared with application of the Kruskal-Wallis test followed by the Dunnet's multiple comparison test. All other variables were submitted to analysis of variance (ANOVA) followed by Tukey's test. The different diets had an impact on the rumen environment (p<0.05) of the heifers assessed, with momentary general depression in the first 12 h after sucrose induction (D3), as well as mild clinical signs in D4. The animals in D3 and D4 presented lower motility (p<0.05) and ruminal pH (p<0.01) than those in D1. Of the 40 heifers, 27.5% (n=11) showed gross lesions in the epithelium of ruminal pillars, whereas 22.5% (n=9) of those in D3 and D4 presented these lesions. Sole corium thickness varied between heifers in D3 compared with those in D1 and D2 (p<0.05). Therefore, high-energy diets, as used in this study, alter some clinical parameters and the rumen environment, causing lesions in the rumen mucosa, and of lesser intensity, in the hoof corium and laminae, suggestive of laminitis.(AU)

O objetivo deste trabalho foi identificar alterações macroscópicas e microscópicas provocadas por dietas de alto valor energético no ambiente ruminal e casco de bovinos de corte (Bos taurus) em confinamento. Foram utilizadas 40 novilhas mantidas em confinamento, sendo divididas em 4 grupos experimentais: Grupo D1(controle) - 48% de volumoso e 52% de concentrado; Grupo D2 - 30% de volumoso e 70% de concentrado; Grupo D3 - 30% de volumoso e 70% de concentrado + sacarose; Grupo D4 - 100% de concentrado. Foi realizado exame clínico dos animais, avaliação do pH ruminal, da claudicação, além de coletas de amostras post-mortem para análises histopatológicas da região laminar do casco, coxim digital e do rúmen. Todas as variáveis dependentes do estudo foram comparadas por meio do software estatístico SPSS 20.0. As variáveis sem normalidade (FC, MR, Tc e TPC) foram comparadas pelo teste de Kruskal Wallis, seguido pelo teste de comparação múltipla de Dunnet. Todas demais foram submetidas a análise de variância (ANOVA), seguida pelo teste de Tukey. Foi observado impacto das distintas dietas ao ambiente ruminal (p<0,05). Os grupos D3 e D4 exibiram menor motilidade (p<0,05) e pH ruminal (p<0,01). 27,5% (n=11) dos animais tiveram registros macroscópicos de lesões no epitélio dos pilares ruminais enquanto que os submetidos às dietas 3 e 4 foi observada ocorrência de 22,5% (n=9) de lesões macroscópicas no rúmen. As espessuras do córium solear variaram entre os grupos que receberam a indução de sacarose em relação ao grupo controle e novilhas alimentadas com a dieta 2 (p<0,05). Sendo assim dietas com elevada densidade energética, na condição em que foi empregada, alteraram alguns parâmetros clínicos e o ambiente ruminal, provocando lesões na mucosa do rúmen e de pouca intensidade no córium e tecido laminar, sugestiva de laminite.(AU)