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91.
92.
de Carvalho Menezes de Almeida Sheylla Foligno Souza-Fabjan Joanna Maria Gonçalves Balaro Mario Felipe Alvarez Bragança Gláucia Mota Pinto Pedro Henrique Nicolau de Almeida José Gabriel Moura Ana Beatriz Bossois da Fonseca Jeferson Ferreira Brandão Felipe Zandonadi 《Tropical animal health and production》2018,50(2):427-432
Tropical Animal Health and Production - This study evaluated the effect of two doses of prostaglandin at different intervals on reproductive parameters of crossbred ewes. In Experiment 1, 30 ewes... 相似文献
93.
A. Rezaeenia A. A. Naserian R. Valizadeh A. M. Tahmasbi A. Mokhtarpour 《Tropical animal health and production》2018,50(7):1427-1433
The objective of this experiment was to investigate the influence of ground date seed (GDS) on intake, digestibility, and milk yield and milk fatty acid (FA) composition of lactating Holstein cows. The experimental design was a 4?×?4 replicated Latin square with eight lactating dairy cows with an average milk production of 35.5?±?1.5 kg and 75?±?5 days in milk (DIM). Dairy cows were fed one of the four treatments contained 0, 2, 4, and 6% of diet dry matter (DM) GDS in replacement of wheat bran. All diets contained the same amount of forages (alfalfa hay and corn silage). Dietary treatments had no effect on DM intake (DMI), total tract apparent digestibility, milk yield, and milk composition. Increasing GDS linearly decreased concentration of C13:0 and increased cis-9 C14:1 and trans-11 C18:1 (vaccenic acid) (P?<?0.05). A linear tendency for more C16:1 content in milk fat was observed with increasing GDS (P?=?0.06). Feeding GDS resulted in a linear decrease (P?<?0.01) in saturated FA (SFA) but increased milk fat monounsaturated FA (MUFA) and trans FA (TFA) (P?<?0.05). Therefore, low levels of GDS (up to 6%) in the diet of Holstein dairy cows can beneficially modify milk FA composition without any adverse effects on intake, digestibility, and milk yield. 相似文献
94.
V. Arthy R. Venkataramanan S. N. Sivaselvam C. Sreekumar D. Balasubramanyam 《Tropical animal health and production》2018,50(7):1463-1471
The Network Project on Sheep Improvement (NWPSI)–Madras Red field unit is a group breeding scheme involving 198 farmers’ flocks of Madras Red sheep in which selection for growth traits and rotation of rams have been practised for over two decades. Growth data collected from these flocks were used to evaluate the performance and understand the direct and expected responses to selection based on genetic parameters. The body weight at birth (BW), weaning weight (WW), 6-month weight (6W), 9-month weight (9W), 12-month weight (YW), pre-weaning average daily gain (ADG1, birth to 3 months), post-weaning ADG2 (3–6 months), ADG3 (6–9 months), ADG4 (9–12 months) and ADG5 (3–12 months) were 2.67, 10.05, 14.56, 18.36, 21.36, 80.13, 49.05, 43.00, 34.21 and 41.18 g, respectively. Univariate analyses were carried out using animal and sire models to estimate variance components. Heritability obtained from animal model for BW was 0.36 and the values for other body weight traits were almost unity. Heritability estimate for pre-weaning ADG1 was 0.31. Very high genetic variability was observed in spite of long-term selection and this sustenance of variability is one of the main advantages of a group breeding scheme, combining several flocks of smaller size. An increasing genetic and phenotypic trend was noticed for almost all the traits studied. The expected responses calculated based on genetic parameters also indicated scope for improvement. 相似文献
95.
Azarpajouh S. Marchewka J. Segura Correa J. C. Calderón Díaz J. A. 《Tropical animal health and production》2018,50(6):1343-1348
Tropical Animal Health and Production - The objective of this study was to compare hoof anatomy, hoof growth pattern, and hoof weight-bearing surface of six different Iranian sheep breeds to... 相似文献
96.
B. Poźniak K. Motykiewicz‐Pers T. Grabowski M. Świtała 《Journal of veterinary pharmacology and therapeutics》2018,41(1):163-165
The aim of this study was to assess the influence of growth on the pharmacokinetics of sodium salicylate (SS) in male turkeys. SS was administered intravenously at a dose of 50 mg/kg. Plasma drug concentrations were assessed by high‐performance liquid chromatography, and pharmacokinetic parameters were calculated by noncompartmental analysis. As the age increased from 6 to 13 weeks (body weight increase from 2.35 to 9.43 kg), median body clearance decreased from 1.34 to 0.87 ml/min/kg. This caused a significant increase in the median mean residence time from 3.42 to 4.44 hr. Elimination phase proved to be biphasic and two elimination half‐lives (T1/2el) were distinguished. Whereas T1/2el1 was found to increase with age by 128%, T1/2el2 represented a later but faster and less age‐dependent phase of elimination (increase by 56% in the respective groups). Volume of distribution decreased with age. These effects may lead to different therapeutic response to SS in turkeys of different age and body weights. 相似文献
97.
P. K. Randleff-Rasmussen A. Leblond J. Cappelle J. Bontemps S. Belluco M. R. Popoff C. Marcillaud-Pitel J. Tapprest P. Tritz I. Desjardins 《Veterinary research communications》2018,42(1):19-27
Equine grass sickness (EGS) (equine dysautonomia) is a neurodegenerative condition of grazing equines. Pre-mortem diagnosis of EGS is a challenge for practitioners as definitive diagnosis requires ileal/myenteric lymph node biopsies. This study aimed to develop a clinical score that could be used by practitioners to improve the detection of acute or subacute EGS cases in the field. Suspected EGS cases were declared by veterinary practitioners. A case was classified as confirmed positive if ileal or rectal biopsy samples showed neuronal degeneration typical of EGS. A semi-quantitative scoring system, including epidemiological and clinical data, was created to attempt to classify suspected EGS horses into confirmed positive or negative cases. Each variable was weighted based on a boosted regression trees model, while taking into account its clinical relevance. Twenty-eight EGS cases were confirmed by biopsy during the entire study period. The best cut-off value for the score to have a high sensitivity while maximizing specificity was 8, with a sensitivity of 100% and a specificity of 53%. In our dataset, 77% of animals would be correctly classified with this cut-off value of 8. Highest sensitivity was chosen in order to detect the highest number of potential cases. Our score represents an inexpensive and useful tool to aid in the identification of suspected EGS cases in the field and selection for further diagnostics procedures to confirm or rule out the disease. Application of the score to larger populations of animals would be required to further adapt and refine the score. 相似文献
98.
Nathaly Enciso Luciana L. K. Ostronoff Guillermo Mejías Leticia G. León María Luisa Fermín Elena Merino Cristina Fragio Luis Avedillo Concepción Tejero 《Veterinary research communications》2018,42(1):29-38
Adult Mesenchymal Stem Cells (MSC) are cells that can be defined as multipotent cells able to differentiate into diverse lineages, under appropriate conditions. These cells have been widely used in regenerative medicine, both in preclinical and clinical settings. Initially discovered in bone marrow, MSC can now be isolated from a wide spectrum of adult and foetal tissues. Studies to evaluate the therapeutic potential of these cells are based on their ability to arrive to damaged tissues. In this paper we have done a comparative study analyzing proliferation, surface markers and OCT4, SOX9, RUNX2, PPARG genes expression in MSC cells from Bone marrow (BMMSC) and Adipose tissue (ASC). We also analyzed the role of Stem Cell Factor (SCF) on MSC proliferation and on ASCs metalloproteinases MMP-2, MMP-9 secretion. Healthy dogs were used as BMMSC donors, and ASC were collected from omentum during elective ovariohysterectomy surgery. Both cell types were cultured in IMDM medium with or without SCF, 10% Dog Serum (DS), and incubated at 38 °C with 5% CO2. Growth of BMMSCs and ASCs was exponential until 25–30 days. Flow citometry of MSCs revealed positive results for CD90 and negative for CD34, CD45 and MCH-II. Genes were evaluated by RT-PCR and metalloproteinases by zymografy. Our findings indicate morphological and immunological similarities as well as expression of genes from both origins on analyzed cells. Furthermore, SCF did not affect proliferation of MSCs, however it up-regulated MMP-2 and MMP-9 secretion in ASCs. These results suggest that metalloproteinases are possibly essential molecules pivoting migration. 相似文献
99.
Daniel A. Truchado Michaël A. J. Moens Sergio Callejas Javier Pérez-Tris Laura Benítez 《Veterinary research communications》2018,42(2):111-120
Papillomaviruses are non-enveloped, DNA viruses that infect skin and mucosa of a wide variety of vertebrates, causing neoplasias or simply persisting asymptomatically. Avian papillomaviruses, with six fully sequenced genomes, are the second most studied group after mammalian papillomaviruses. In this study, we describe the first oral avian papillomavirus, detected in the tongue of a dead Yorkshire canary (Serinus canaria) and in oral swabs of the same bird and other two live canaries from an aviary in Madrid, Spain. Its genome is 8,071 bp and presents the canonical papillomavirus architecture with six early (E6, E7, E1, E9, E2, E4) and two late open reading frames (L1 and L2) and a long control region between L1 and E6. This new avian papillomavirus L1 gene shares a 64% pairwise identity with FcPV1 L1, so it has been classified as a new species (ScPV1) within the Ethapapillomavirus genus. Although the canary died after showing breathing problems, there is no evidence that the papillomavirus caused those symptoms so it could be part of the oral microbiota of the birds. Hence, future investigations are needed to evaluate the clinical relevance of the virus. 相似文献
100.
María Teresa Tejedor-Junco Margarita González-Martín Estefanía Bermeo-Garrido Rebeca Villasana-Loaiza Elena Carretón-Gómez 《Veterinary research communications》2018,42(3):227-232
Doxycycline is an antibiotic that, in addition to the classic antibacterial use, is also prescribed to fight parasitic diseases, like heartworm disease in dogs. Despite the concern that the overuse of this antibiotic may decrease susceptibility of clinically important bacteria, the consequences of the prolonged doxycycline therapy in heartworm-infected dogs have never been studied before. We have analyzed the impact of this therapy on Staphylococcus aureus and Enterococcus antimicrobial resistance. In this study, 17 heartworm-infected dogs (10 that had completed the doxycycline treatment and 7 dogs that had not yet begun) were included. Twenty-four isolates of Staphylococcus aureus were obtained from two locations of each dog. After treatment, 73.3% of isolates were resistant to at least one antibiotic but only 22.2% of isolates before treatment. Most of doxycycline resistant isolates were obtained from dogs that have received treatment. Erythromycin resistance or intermediate susceptibility was detected in 45.6% of isolates, most of them from dogs after treatment. For Enterococci, 48 isolates were obtained from fecal samples (25 before treatment and 23 after treatment). Before treatment, 32% of isolates were resistant at least to one antibiotic while after, this data increase up to 65%. Comparing isolates before and after treatment, a clear increase in resistance to doxycycline (12% against 21.74%) and erythromycin (20% against 39.13%) was observed. Although the present work is a preliminary research, the results encourages the development of further studies to determinate the effect of prolonged doxycycline therapy on antimicrobial resistance. 相似文献