Potential benefits of a blend of essential oils on metabolism, digestibility, organ development and gene expression of dairy calves.

The objective of this study was to evaluate blood cells and metabolites, insulin-like growth factor-1 (IGF-1), digestibility, internal organs weight and histology, gene expression, and spleen cell proliferation of pre-weaned bull calves supplemented with a blend of essential oils in milk replacer (MR). Sixteen newborn Holstein?×?Gyr crossbred dairy bull calves, with body weight at birth of 33.3?±?3.7 kg, were housed in individual sand bedded pens, blocked by genetic composition, and randomly assigned to 1 of 2 treatments in a randomized complete block design: Control (CON, n?=?8) and blend of essential oils supplementation (BEO, n?=?8, 1 g/day/calf, Apex Calf, Adisseo, China). The commercial blend was composed by plant extracts derived from anise, cinnamon, garlic, rosemary, and thyme. Animals were fed 5 L of MR/day reconstituted at 15% (dry matter basis), divided into two equal meals. Water and starter were provided ad libitum. ß-hydroxybutyrate, urea, and glucose were evaluated weekly, IGF-1 was evaluated biweekly, and total blood cell count was performed every four weeks until the end of the trial at eight weeks of age. Feed samples were collected three times a week and polled for weekly analysis. Apparent total nutrient digestibility was determined from d 56 to 60 of age. On d 60?±?1, animals were euthanized for organ weight, histology, spleen cell proliferation, and intestinal gene expression analysis. Data were analyzed independently using linear mixed models using the REML method in the nlme package in R for continuous outcomes. A non-parametric test was used for ordered categorical outcomes using the Artools package in R. There were no differences between groups for blood evaluations, digestibility, gene expression, and a spleen cell proliferation assay. However, BEO calves presented a heavier pancreas, heavier intestines, bigger ileum villi, and higher cecum butyrate levels (P?<?0.05), demonstrating that the EO supplementation helped intestinal development and symbiotic bacteria. It was also observed in CON animals? heavier respiratory tract and a higher eosinophil count (P?<?0.05). Therefore, the organs where eosinophils are more active had a better response for BEO animals. No differences were found in the intestinal gene expression in the immune context. These results demonstrate that supplementing essential oils in MR could contribute to gut development and immune function. However, more research is needed to understand its impact on body development and define the best dosage and route of administration

Quimionucleólise cervical associada à espondilectomia ventral em cães: aspectos clínico-cirúrgicos, radiográficos e histológicos

Foram avaliados aspectos clínico-cirúrgicos, radiográficos e histológicos de discos intervertebrais cervicais caninos após quimionucleólise com quimiopapaína associada à espondilectomia ventral em 24 cães. Em todos foi realizada a espondilectomia ventral na região do disco intervertebral C2-C3 e quimionucleólises nos demais discos cervicais. Os cães foram sacrificados às 24 horas, e aos 8, 30, 60, 90 e 120 dias após aplicação da enzima para a obtenção de cortes sagitais dos discos intervertebrais tratados e das estruturas cartilaginosas e ósseas adjacentes. Nos mesmos períodos, foram realizadas radiografias para monitoração da espessura dos espaços intervertebrais. Todos toleraram bem o procedimento cirúrgico e não apresentaram alterações clínicas significativas. Na avaliação radiográfica, observou-se marcada redução dos espaços intervertebrais 24 horas após o tratamento. Do oitavo ao 90º dia após aplicação da enzima, foi verificada ausência total de espaço intervertebral na região dos discos tratados. Aos 120 dias, as espessuras dos espaços intervertebrais corresponderam, em média, a 59,1% da espessura anterior ao procedimento. Na avaliação histológica, foram observadas digestão nuclear e redução da intensidade de coloração pela safranina-O 24 horas após a quimionucleólise. A partir do 60º dia, havia material amorfo no espaço nuclear, que, aos 120 dias, tinha aparência fibrocartilaginosa. A quimionucleólise associada à espondilectomia ventral determinou a lise dos discos intervertebrais e lesões nas estruturas cartilaginosas e ósseas adjacentes, com tendência à reparação por tecido fibrocartilaginoso ao longo do tempo.The clinical-surgical, radiological, and histological aspects of chemonucleolysis with chymopapain in canine cervical intervertebral disks associated to ventral slot in 24 dogs were evaluated. The ventral slot was accomplished in the area of the intervertebral disks C2-C3 and chemonucleolysis in the other cervical disks. The dogs were clinically and radiographically monitored for up to 120 days. Each group of four animals was submitted to euthanasia with an anesthetic overdose at 24 hours, and at 8, 30, 60, 90, and 120 days after the enzyme injection for the acquisition of sagittal sections of the treated disks, as well as adjacent cartilaginous endplates and bony structures. In this study, all dogs tolerated the surgical procedure, without detectable postoperative pain or neurological deficit. In the radiographic evaluation, it was observed consistent disk space narrowing 24 hours after the procedure and total absence of space from the 8th to the 90th day of postoperative in the area of all treated disks. However, 120 days after treatment, there was an increase in disk height, corresponding on average to 59.1% of the preinjection value. In the histological evaluation, it was observed nuclear digestion and decrease of safranin-O staining intensity 24 hours after disk injection. At eight days, the nuclear content was still vacuolated, but more fibrillar. An irregularly defined mass was observed in the nuclear space on days 60th and 90th, but it seemed fibrocartilaginous tissue on day 120th. Chemonucleolysis with chymopapain associated to the ventral slot in the cervical column of dogs determined lysis of intervertebral disks, cervical instability, and lesions of cartilaginous and bone adjacent structures that tend to repair with fibrocartilaginous tissue along the time