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111.
112.
Wendell F. G. da Cruz Jon P. Schoonmaker Flavio D. de Resende Gustavo R. Siqueira Liziana M. Rodrigues Germn D. R. Zamudio Marcio M. Ladeira 《Animal Science Journal》2019,90(9):1200-1211
The study aimed to evaluate nutrient digestibility and intestine gene expression in the progeny from cows supplemented during gestation and fed diets with or without rumen‐protected fat (RPF) in the feedlot. Forty‐eight Nellore steers, averaging 340 kg, were housed in individual pens and allotted in a completely randomized design using a 2 × 2 factorial arrangement (dams nutrition × RPF). Cows' supplementation started after 124 ± 21 days of gestation. The feedlot lasted 135 days and diets had the inclusion of zero or 6% of RPF. Digestibility was evaluated by total feces collection. Steers were slaughtered using the concussion technique and samples of pancreas and small intestine were collected immediately after the slaughter to analyze α‐amylase activity, and the expression of SLC5A1, CD36, and CCK and villi morphometry. Feeding RPF increased nutrients digestibility (p < 0.01). There was no effect of maternal nutrition on digestibility and α‐amylase activity in steers (p > 0.05). Duodenal expression of SLC5A1, CD36, and CCK increased in the progeny from restricted cows. In conclusion, protein restriction during mid to late gestation of dams has long‐term effects on small‐intestine length and on expression of membrane transporters genes in the duodenum of the progeny. However, maternal nutrition does not affect digestibility in the feedlot. 相似文献
113.
Carlos Alberto Alves de Oliveira Filho José Augusto Gomes Azevêdo Gleidson Giordano Pinto de Carvalho Camilla Flávia Portela Gomes da Silva Ícaro dos Santos Cabral Luiz Gustavo Ribeiro Pereira Larissa Gomes dos Reis Flávio Moreira de Almeida Lígia Lins Souza 《Tropical animal health and production》2016,48(2):289-295
114.
Daniel Ribeiro Menezes Roberto Germano Costa Gherman Garcia Leal de Araújo Luiz Gustavo Ribeiro Pereira Geovergue Rodrigues de Medeiros Juliana Silva Oliveira Thiago Vinicius Costa Nascimento Rafael Torres de Souza Rodrigues José Morais Pereira Filho Karina Costa Busato 《Tropical animal health and production》2016,48(2):297-302
115.
Irene COBO‐SIM
N Beln MNDEZ‐CEA Hctor PORTILLO Fausto ELVIR Hermes VEGA Francisco Javier GALLEGO Gustavo FONTECHA 《Integrative zoology》2019,14(5):422-434
Biosphere reserves are protected areas whose purpose is to combine conservation and sustainable development. However, their effectiveness has not been tested sufficiently, especially from an ecological and genetic approach. In this sense, the Peromyscus genus represents an excellent bioindicator to address these questions, due to its short life and high evolutionary rate and fecundity. For conservation managers, genetic structure can increase the rate of loss of genetic diversity because alleles exclusive of a subpopulation are more likely to disappear as a consequence of genetic drift in comparison with a panmictic population. Here we analyzed the abundance, movement distances, morphology/morphometry and genetic structure of 3 populations of Mexican deer mouse (Peromyscus mexicanus) located in different protected zones of La Tigra National Park (Honduras). Our results are consistent among the 3 approaches and showed the highest values of abundance, morphometry and genetic diversity in the population located at the core zone, whereas non‐statistically significant differences were found between buffer and transition zone populations, suggesting suitable effectiveness of conservation management in the core zone but a lack of ecological buffering function of the other zones. In addition, the low movement distances and high genetic structure among the studied populations provide evidence of poor conservation management in the buffer and transition zone. Thus, we discuss the utility of the novel methodology used in this work, combining morphometry, abundance and genetics, in testing the effectiveness of conservation strategies in biosphere reserves, and the value of the Peromyscus genus as a bioindicator. 相似文献
116.
117.
Does virginiamycin supplementation affect the metabolism and performance of Nellore bulls grazing under low and high gain rates? 下载免费PDF全文
João Paulo R. Costa Raphael B. De Jesus Ivanna M. Oliveira Flávio D. Resende Gustavo R. Siqueira Euclides B. Malheiros 《Animal Science Journal》2018,89(10):1432-1441
This study aimed to evaluate the effect of virginiamycin on the metabolism and performance of growing Nellore bulls under low and high gain rates on pasture. In experiment 1, 80 Nellore bulls (age = 12 ± 2 months, body weight = 258 ± 15 kg) were assigned to 16 paddocks in a 2 × 2 randomized block factorial arrangement. In experiment 2, 12 cannulated Nellore bulls were assigned to three 4 × 4 balanced Latin squares. The factors were: (1) mineral salt without or with virginiamycin, and (2) low or high gain rate. No interaction was noted between factors (p > .10). Animals fed virginiamycin had greater average daily gain (14%, p < .01), body weight (11 kg, p = .05), plasma nonesterified fatty acid (20%, p < .01), serum calcium concentration (2.62%, p = .04), and total protozoa (p = .03) and had the same bacterial proportion (p > .27). Animals with a low gain rate had greater serum urea concentration (19.6%, p < .01) and ruminal ammonia nitrogen (62%, p < .01). Thus, virginiamycin increases the performance and changes the metabolism of growing Nellore bulls under low and high gain rates on pasture. 相似文献
118.
Matheus V. L. Moreira Maria C. de Andrade Gustavo O. Fulgêncio Ingeborg M. Langohr Roselene Ecco 《Veterinary ophthalmology》2018,21(5):535-538
An indoor‐only, 5‐year‐old, spayed female domestic shorthair cat presented for an ophthalmic examination of the left eye. An intraocular tumor with secondary glaucoma and blindness was diagnosed; the globe was enucleated and sent for histopathological examination. Gross examination revealed a solid white mass filling the entire vitreous space and replacing the iris and ciliary body. The lens and retina appeared to be similarly replaced by the neoplasm. Histological examination revealed a complete loss of the internal ocular structures, with a ruptured capsule as the only remnant of the lens within an extensive malignant mesenchymal neoplastic cell proliferation. The cells were polygonal, with well‐defined cytoplasmic borders and abundant weakly basophilic cytoplasm, embedded within the islands of chondroid matrix. No neoplastic invasion of the sclera was apparent. The animal died 6 months after the enucleation due to respiratory distress. Gross examination revealed numerous firm, white to tan nodular masses with smooth to mildly irregular surfaces dispersed throughout the parietal pleura, thoracic surface of the diaphragm, tracheobronchial and mediastinal lymph nodes, pericardium, and lungs. On cross‐section, the neoplastic nodules were solid and variably translucent, resembling hyaline cartilage. Histologically, these nodules were similar to the neoplasm identified earlier in the left globe. Metastasis of post‐traumatic ocular chondrosarcoma has not yet been described in cats. This is therefore believed to be the first report of metastases of this type of neoplasm in cats. This case adds to the limited set of data on the outcome of this type of tumor. 相似文献
119.
Fabian A. Figueroa Roberto T. Abdala-Díaz Claudia Prez Virginia Casas-Arrojo Aleksandra Nesic Cecilia Tapia Carla Durn Oscar Valdes Carolina Parra Gastn Bravo-Arrepol Luis Soto Jos Becerra Gustavo Cabrera-Barjas 《Marine drugs》2022,20(7)
Codium bernabei is a green alga that grows on Chilean coasts. The composition of its structural polysaccharides is still unknown. Hence, the aim of this work is to isolate and characterize the hot water extracted polysaccharide fractions. For this purpose, the water extracts were further precipitated in alcohol (TPs) and acid media (APs), respectively. Both fractions were characterized using different physicochemical techniques such as GC-MS, GPC, FTIR, TGA, and SEM. It is confirmed that the extracted fractions are mainly made of sulfated galactan unit, with a degree of sulfation of 19.3% (TPs) and 17.4% (ATs) and a protein content of 3.5% in APs and 15.6% in TPs. Other neutral sugars such as xylose, glucose, galactose, fucose, mannose, and arabinose were found in a molar ratio (0.05:0.6:1.0:0.02:0.14:0.11) for TPs and (0.05:0.31:1.0:0.03:0.1:0.13) for ATs. The molecular weight of the polysaccharide samples was lower than 20 kDa. Both polysaccharides were thermally stable (Tonset > 190 °C) and showed antioxidant activity according to the ABTS•+ and DPPH tests, where TPs fractions had higher scavenging activity (35%) compared to the APs fractions. The PT and APTTS assays were used to measure the anticoagulant activity of the polysaccharide fractions. In general, the PT activity of the TPs and APs was not different from normal plasma values. The exception was the TPs treatment at 1000 µg mL−1 concentration. The APTTS test revealed that clotting time for both polysaccharides was prolonged regarding normal values at 1000 µg mL−1. Finally, the antitumor test in colorectal carcinoma (HTC-116) cell line, breast cancer (MCF-7) and human leukemia (HL-60) cell lines showed the cytotoxic effect of TPs and APs. Those results suggest the potential biotechnological application of sulfate galactan polysaccharides isolated from a Chilean marine resource. 相似文献
120.
Cássia M Molinaro Coelho Juan C Duque Moreno Daniel da S Goulart Leandro B Caetano Lorena K Soares Gustavo H Coutinho Geraldo ES Alves Luiz Antonio F da Silva 《Veterinary anaesthesia and analgesia》2014,41(6):602-612
ObjectivesTo evaluate the cardiorespiratory and biochemical effects of ketamine-propofol (KP) or guaifenesin-ketamine-xylazine (GKX) anesthesia in donkeys.Study designProspective crossover trial.AnimalsEight healthy, standard donkeys, aged 10 ± 5 years and weighing 153 ± 23 kg.MethodsDonkeys were premedicated with 1.0 mg kg?1 of xylazine (IV) in both treatments. Eight donkeys were administered ketamine (1.5 mg kg?1) and propofol (0.5 mg kg?1) for induction, and anesthesia was maintained by constant rate infusion (CRI) of ketamine (0.05 mg kg?1 minute?1) and propofol (0.15 mg kg?1 minute?1) in the KP treatment. After 10 days, diazepam (0.05 mg kg?1) and ketamine (2.2 mg kg?1) were administered for induction, and anesthesia was maintained by a CRI (2.0 mL kg?1 hour?1) of ketamine (2.0 mg mL?1), xylazine (0.5 mg mL?1) and guaifenesin (50 mg mL?1) solution. Quality of anesthesia was assessed along with cardiorespiratory and biochemical measurements.ResultsAnesthetic induction took longer in GKX than in KP. The induction was considered good in 7/8 with KP and in 6/8 in GKX. Anesthetic recovery was classified as good in 7/8 animals in both treatments. Xylazine administration decreased heart rate (HR) in both treatments, but in KP the HR increased and was higher than GKX throughout the anesthetic period. Respiratory rate was higher in GKX than in KP. PaO2 decreased significantly in both groups during the anesthetic period. Glucose concentrations [GLU] increased and rectal temperature and PCV decreased in both treatments. Arterial lactate [LAC] increased at recovery compared with all time points in KP. [GLU] and calcium were higher in GKX than in KP at recovery.Conclusion and clinical relevanceThese protocols induced significant hypoxemia but no other cardiorespiratory or metabolic changes. These protocols could be used to maintain anesthesia in donkeys, however, they were not tested in animals undergoing surgery. 相似文献