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81.
82.
83.
Effect of Megasphaera elsdenii NCIMB 41125 dosing on rumen development,volatile fatty acid production and blood β‐hydroxybutyrate in neonatal dairy calves 下载免费PDF全文
M. C. Muya F. V. Nherera K. A. Miller C. C. Aperce P. M. Moshidi L. J. Erasmus 《Journal of animal physiology and animal nutrition》2015,99(5):913-918
Thirty calves were randomly assigned to two treatments and fed until weaning [42 days (d) of age]. Treatments were a control group (n = 15), which did not receive Megasphaera elsdenii (Me0) and a M. elsdenii group, which received a 50‐ml oral dose of M. elsdenii NCIMB 41125 (108 CFU/ml) at day 14 day of age (Me14). Calves were given colostrum for the first 3 day followed by limited whole milk feeding. A commercial calf starter was offered ad libitum starting at day 4 until the end of the study. Fresh water was available throughout the study. Feed intake and growth were measured. Blood samples were collected via jugular venipuncture to determine β‐hydroxybutyrate (BHBA) concentrations. Fourteen male calves (seven per group) were euthanised on day 42 and digestive tracts harvested. Reticulo‐rumen weight was determined and rumen tissue samples collected from the cranial and caudal sacs of the ventral and dorsal portions of the rumen for measurements of papillae length, papillae width and rumen wall thickness. Dosing with M. elsdenii NCIMB 41125 improved starter dry matter intake (DMI), weaning body weight (BW) and tended to improve average daily gain. Calves in Me14 group had greater plasma BHBA concentration than Me0‐calves during the last 3 weeks of the trial and had at day 42 greater reticulo‐rumen weight, papillae width and papillae density compared to Me0. No differences in rumen wall thickness or papillae length were observed between the two groups. Total volatile fatty acids, acetate and propionate production did not differ between treatments, but butyrate production was greater in Me14 than Me0. Dosing M. elsdenii NCIMB 41125 showed benefit for calves with improved feed intake and rumen development suggesting increased epithelium metabolism and improved absorption of digestive end products. 相似文献
84.
Effect of Relaxin on Fertility Parameters of Frozen–Thawed Buffalo (Bubalus bubalis) Sperm 下载免费PDF全文
AR Elkhawagah V Longobardi G Neglia A Salzano G Zullo GA Sosa G Campanile B Gasparrini 《Reproduction in domestic animals》2015,50(5):756-762
The aim of this work was to evaluate the effect of relaxin on fertility parameters of buffalo frozen/thawed sperm. Sperm were incubated in the absence of capacitating agents (negative control), with a known capacitating agent such as heparin (positive control) and with 50 and 100 ng/ml relaxin for 2 and 4 h. Sperm viability, motility, capacitation and the effect of relaxin on the fertilizing ability after heterologous IVF were evaluated. Although viability was not affected, relaxin increased (p < 0.05) sperm motility compared to the negative and positive controls both after 2 h (60.0 ± 2.0, 60.0 ± 3.1, 68.3 ± 1.7 and 69.4 ± 2.7, respectively, in negative control, positive control, 50 and 100 ng/ml relaxin) and 4 h (55.0 ± 2.5, 53.3 ± 3.0, 62.2 ± 3.0 and 65.0 ± 3.2, respectively, in negative control, positive control, 50 and 100 ng/ml relaxin) incubation. When sperm were incubated with both 100 ng/ml relaxin and heparin, a decrease (p < 0.01) of pattern A, that is low capacitation level, was observed compared to the negative control both after 2 h (54.4, 34.3 and 36.4%, respectively, in negative control, positive control and 100 ng/ml relaxin) and 4 h (51.9, 35.0 and 34.3%, respectively, in negative control, positive control and 100 ng/ml relaxin). Moreover, an increase (p < 0.01) of pattern EA, that is high capacitation level, was recorded with 100 ng/ml relaxin and heparin compared to the negative control both after 2 h (44.1, 59.3 and 57.7%, respectively, in negative control, positive control and 100 ng/ml relaxin) and after 4 h (43.0, 54.4 and 56.0%, respectively, in negative control, positive control and 100 ng/ml relaxin). Finally, relaxin increased (p < 0.01) cleavage rate compared to the negative control (57.1 ± 4.4, 72.5 ± 6.0, 71.4 ± 5.5 and 73.6 ± 2.9, respectively, in negative control, positive control, 50 and 100 ng/ml relaxin). In conclusion, relaxin has a beneficial effect on motility, capacitation and fertilizing ability of frozen–thawed buffalo sperm. 相似文献
85.
Effect of Testosterone Administration and Spiking on Reproductive Success of Broiler Breeder Flocks 下载免费PDF全文
B Ordas S Vahedi A Seidavi M Rahati V Laudadio V Tufarelli 《Reproduction in domestic animals》2015,50(5):820-825
Age negatively affects reproductive success of broiler breeder flocks. One of the main hormones involved in the change of fertility with the age is testosterone (TT). The introduction of young males at later production stages of broiler flocks is known as spiking and is expected to reduce the fertility decline with age. The aim of this study was to determine the effect of injection of different levels of TT and the effect of spiking on reproductive fitness of broiler breeder flocks. Two experiments were conducted on Ross 308 breeder flocks for 10 weeks (41–50 weeks of age). The experiment 1 included a control and three treatments corresponding to three doses of TT (0.1, 0.2 and 0.3 cc), while the experiment 2 included a control and one treatment corresponding to spiking. The lower dose of TT (0.1 cc) and the spiking clearly slowed down the decline in hatchability. Therefore, either the external administration of TT to the males when the natural concentration of TT starts to decline or spiking the breeder flock with young roosters could contribute to improve reproductive success in later stages of the production cycle in broiler breeder flocks. 相似文献
86.
VJC Santos K Simplício D Sanchez L Coutinho P Teixeira F Barros V Almeida L Rodrigues P Bartlewski M Oliveira M Feliciano W Vicente 《Reproduction in domestic animals》2015,50(2):251-255
This study aimed to evaluate the sonographic characteristics of the udder and teats and to determine the Doppler indexes of mammary artery in healthy and undergoing subclinical and clinical mastitis goats. Thirty animals among Saanen and Alpine Brown goats were arranged in three groups, healthy goats (HG), goats with subclinical mastitis (SMG) and goats with clinical mastitis (CMG). Using the B‐mode, the sonographic characteristics (echotexture and echogenicity) and biometry (diameter and area of the udder cistern, diameter and area of the teat cistern and thickness of the teat wall) were evaluated. Using Doppler ultrasonography, the vascular indexes of the mammary artery were obtained. It was observed hyperechogenicity with solid component in the gland cistern when comparing animals with clinical mastitis and healthy mammary tissue. Regarding the echotexture of the breast tissue, there was heterogeneity in the mammary parenchyma on the three groups, for the milk, it was observed homogeneity for animals on HG and SMG and heterogeneity for animals on CMG. Grey‐scale quantitative assessment revealed increase in echogenicity (mean value) for all the structures when comparing the three groups. Biometry did not reveal statistical difference between groups, for none of the evaluated structures. Doppler examination of the mammary artery showed the decrease of end diastolic velocity and raise of pulsatility index between groups. The association of B‐mode and Doppler ultrasonography is useful for the evaluation of the udder of dairy goats with mastitis. It is a sensitive and specific method for the study of this disease. Doppler mode was unable to establish reliable criteria for diagnosis of subclinical mastitis. Moreover, the quantification of echogenicity is a useful technique for the evaluation of the milk in animals with mastitis; therefore, it is suggested that it can be used as complementary technique for the diagnosis of mastitis in goats. 相似文献
87.
Denise R. Freitas Leorges M. Fonseca Fernando N. Souza Cristiane V. G. Ladeira Soraia A. Diniz João Paulo A. Haddad Diêgo S. Ferreira Mônica M. O. P. Cerqueira 《Animal Science Journal》2015,86(5):553-556
Casein (CN) micelles are colloidal aggregates of protein dispersed in milk, the importance of which in the dairy industry is related to functionality and yield in dairy products. The objective of this work was to investigate the correlation of milk CN micelles diameter from Holstein and Zebu crossbreds with milk composition (protein, fat, lactose, total and nonfat solids and milk urea nitrogen), somatic cell count (SCC), age, lactation stage and production. Average casein micelles diameters of milk samples obtained from 200 cows were measured using photon correlation spectroscopy and multiple regression analysis was used to find relationship between variables. CN micelle diameter, SCC and nonfat solids were different between animals with different Holstein crossbreed ratios, which suggests influence of genetic factors, mammary gland health and milk composition. Overall, results indicate the potential use of CN micelle diameter as a tool to select animals to produce milk more suitable to cheese production. 相似文献
88.
Ocular dimensions,corneal thickness,and corneal curvature in quarter horses with hereditary equine regional dermal asthenia 下载免费PDF全文
89.
V. Martini A. Poggi F. Riondato M. E. Gelain L. Aresu S. Comazzi 《Veterinary and comparative oncology》2015,13(3):281-287
Histopathology and immunohistochemistry are mandatory to solve the differential between canine low‐grade lymphoma and reactive hyperplasia. However, clinicians and owners often show reluctance toward these invasive tests. However, molecular biology techniques are still not sensitive and specific enough to be regarded as a reliable tool for final diagnosis. In humans, flow cytometry (FC) allows a definitive diagnosis of T‐cell lymphoma based on high prevalence of antigen aberrancies. We describe here the immunophenotype of 26 cases of suspect canine small‐clear cell lymphoma, determined by multi‐colour FC. All cases showed antigen aberrancies and therefore neoplasia was always confirmed. As a consequence, we argue that the combined use of cytology and FC allows solving the differential diagnosis between small clear cell lymphoma and non‐neoplastic reactive conditions when histopathology is not available. Further studies are needed to establish if any aberrancy can be considered indicative of specific histotypes. 相似文献
90.
The use of COLD‐PCR,DHPLC and GeneScanning for the highly sensitive detection of c‐KIT somatic mutations in canine mast cell tumours 下载免费PDF全文
The conventional polymerase chain reaction (PCR)/sequencing methods may be poorly suited for the detection of somatic mutations in canine mast cell tumour (MCT) samples owing to limited sensitivity. This study was aimed at establishing novel and more sensitive methods, assessing their limit of detection and comparing their sensitivity with conventional methods.Two different ‘driver’ somatic mutations of c‐KIT, together with the wild‐type counterparts, were cloned in plasmids to prepare standard samples with known concentrations of mutated alleles in a background of wild‐type alleles; the plasmids standards were assayed using either conventional or novel, highly sensitive technique. Conventional PCR/sequencing showed a sensitivity of 50–20%. Conversely, all the novel methods obtained higher sensitivities allowed reaching as low as 2.5–1.2% of the mutated DNA.The study demonstrates that early conventional methods could likely have underestimated the prevalence of KIT mutations of MCTs, therefore affecting the assessment of their relevance in prognosis and tyrosine kinase inhibitor (TKI) treatment effectiveness. 相似文献