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111.
Brenna de Sousa Barbosa Herlon Victor Rodrigues Silva Beatriz Evaristo de Almeida Tabosa Thalles Gothardo Pereira Nunes Francisco Felipe de Magalhes Lúcia Daniel Machado da Silva 《Reproduction in domestic animals》2019,54(12):1630-1636
Sperm morphometry is the tool that confers objectivity to the morphological evaluation by accurately measuring the dimensions of the gamete and its structures. Thus, the aim of the study was to perform a morphometric characterization of the domestic cat sperm. Therefore, sperm samples were collected from twenty pairs of epididymis in a TRIS extender at 37ºC. An aliquot of the sample was used to make a smear with Rose Bengal solution, and afterwards, the morphology and morphometry were analysed. In the morphology, were quantified the percentage of normal sperm cells, morphological changes of head, midpiece and tail. In morphometry, each normal sperm cell was measured for length, width, area and perimeter of head and midpiece, tail length and total length. The parameters ellipticity, elongation, regularity and rugosity were also determined. The percentage of normal sperm was 67.21%. Of the abnormalities, the curled/folded tail, followed by the curved midpiece, abnormal shaped head and detached head were the most quantified. The sperm head presented 5.56 ± 0.01 μm and 3.10 ± 0.01 μm of length and width, respectively. The head area was 16.94 ± 0.05 μm2, while the perimeter was 16.16 ± 0.03 μm. In the derived parameters, the values were as follows: ellipticity of 1.81 ± 0.00; elongation of 21.39 ± 0.12; regularity of 0.81 ± 0.00; and rugosity of 0.14 ± 0.00. The midpiece presented length and width of 7.96 ± 0.01 μm and 0.76 ± 0.01 μm, respectively. The mean length of the sperm tail was 45.12 ± 0.06 μm, and the total cell size was 58.67 ± 0.06 μm. Thus, it was concluded that the cat sperm is an elongated cell, with high rugosity and regularity. The spermatic tail represents more than ¾ of the total length of the cell and the midpiece exceeds the length of the head. 相似文献
112.
A. M. V. Batista A. F. Mustafa G. R. A. Santos F. F. R. de Carvalho J. C. B. Dubeux Jr M. A. Lira S. B. P. Barbosa 《Journal of Agronomy and Crop Science》2003,189(2):123-126
The objective of this study was to determine ruminal degradability of the dry matter (DM) and crude protein (CP) of 10 varieties of spineless cactus (Opuntia spp.) grown in north‐eastern Brazil. Two ruminally fistulated steers were used in a randomized complete block design. Ash, CP, acid detergent fiber, and acid detergent lignin levels ranged from 10.4 to 13.3 %, 6.2–7.7 %, 19.8–24.8 % and 3.4–5.4 %, respectively. Relative to the other cactus varieties, Redonda had the highest (P < 0.05) in situ soluble DM fraction and effective DM degradability. No differences in effective DM degradability were observed between the other cactus varieties. In situ soluble CP fraction ranged from 1.7 % of CP for the 69 IPA/UFRPE variety to 11.1 % of CP for the Gigante variety. Slowly degradable CP fraction and its rate of degradation were similar among the cactus varieties (average 90 % of CP and 9 % h?1, respectively). The cactus variety 69 IP/UFRPE had a lower (P < 0.05) effective ruminal CP degradability (ECPD) than the other varieties, which had a similar ECPD (average 66 % of CP). It was concluded that differences in ruminal degradability exist between cactus varieties, with more variations observed for ruminal DM than for CP degradability. 相似文献
113.
Maria Anete LALLO Lidiana Flora VIDOTO DA COSTA Anuska Marcelino ALVARES-SARAIVA Paulo Ricardo Dell’Armelina ROCHA Diva Denelle SPADACCI-MORENA Fabiana Toshie de Camargo KONNO Ivana Barbosa SUFFREDINI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):171-176
114.
Yatta Linhares Boakari Maria Augusta Alonso Amanda Vallone Riccio Claudia Barbosa Fernandes 《Reproduction in domestic animals》2019,54(6):823-827
In equine management, it is important to predict the approximate foaling date of mares to monitor parturition and allow early identification and intervention of problems during the perinatal period. There are no studies comparing accurate gestational length (GL) when mares are carrying mule foals and no controlled comparisons between GL of mares pregnant with equine or mule foals. Therefore, the objectives of this study were to compare GL of mares pregnant with equine or mule foals and establish normal reference values for GL of mares pregnant with male and female mules. Gestational length of Mangalarga Paulista breed mares pregnant with equine (n = 54) or with mule (n = 54) foals during the breeding seasons of 2007 to 2016 was evaluated. The mean GL was 347.2 ± 1.4 days (range of 326–368 days) and 341.1 ± 1.6 days (range of 307–360 days) for equine and mule pregnancies, respectively. The normal GL reference for mule pregnancies was 316.9–365.3 days. Therefore, GL of equine pregnancies was longer than of mule pregnancies. Gestational length was not different when pregnancies resulted in females or males within each group. This study established an important reference value for normal GL of mule pregnancies, which can be used by practitioners to estimate and predict foaling dates more accurately. 相似文献
115.
Tiago S. Nascimento Isabelle S. M. Silva Maria Cecília M. A. Alves Bruna B. Gouveia Lara Mariane R. Barbosa Taís J. S. Macedo Jamile M. S. Santos Alane P. O. Monte Maria Helena T. Matos Francine F. Padilha Isabel B. Lima‐Verde 《Reproduction in domestic animals》2019,54(1):31-38
This study aimed to characterize the hydroethanolic extract of red propolis (HERP) and nanoparticles containing HERP for using as an additive in the culture medium of isolated ovine preantral follicles. HERP was characterized by high‐performance liquid chromatography (HPLC) and determination of flavonoid content, and the nanoparticles by the mean particle diameter, polydispersity index (PI) and encapsulation efficiency (EE). The effect of HERP (10 and 20 ηg/ml—HERP10 and HERP20 groups) and nanoparticles (NP10 and NP20 groups) on isolated secondary follicles cultured in vitro for 12 days was observed by morphological evaluation, oxidative stress markers (reactive oxygen species—ROS and glutathione—GSH) and active mitochondria. HPLC showed formononetin as the major compound in the HERP (63.92 ± 0.21 μg/mL). The content of flavonoids ranged from 2.14% to 11.00%. The nanoparticles showed mean diameter of 287.5 ± 3.9 and 479 ± 18.1 ηm; PI of 0.117 ± 0.018 and 0.316 ± 0.039; and EE of 67.15% and 41%, respectively, for the NP10 and NP20 groups. After 12 days of culture, HERP20 and NP20 increased (p < 0.05) the percentage of normal follicles compared to NP10. HERP20 showed significantly higher percentages of antrum formation than control medium (MEM) and NP10 (p < 0.05). HERP20 also showed an increase (p < 0.05) in mitochondrial activity compared to the other treatments, except NP20 (p > 0.05), and increased GSH levels (p < 0.05) compared to MEM and HERP10. In conclusion, use of HERP (20 ηg/ml) on in vitro culture of isolated ovine preantral follicles can increase antrum formation, mitochondrial activity and GSH levels. 相似文献
116.
This study examined the effects of leaf pruning intensities at flowering on the green and yellow life and fruit quality of bananas (Musa AAA, cv. Grande Naine). The fruit from banana plants that retained 7, 9, 11 and 13 leaves after pruning were packed in carton boxes of 13.7 kg and stored in a cold room at 14 °C for 21 days to simulate transportation conditions. During this period, eight visual evaluations of fruit peel colour were made. Next, fruits were induced to commercial ripening using ethylene at 100 μl/ml. Four evaluations (every 2 days) on fruit firmness, soluble solids, titratable acidity, fruit weight and peel colour were made to assess fruit yellow life. No interaction between evaluations and number of leaves retained was found for pulp firmness, soluble solid percentage, fruit acidity, fruit weight and maturation grade. The fruit green life and peel colour was similar for plants retaining different number of leaves. After the application of ethylene, there were no differences in fruit firmness (P > 0.62), percentage of soluble solids (P > 0.24) nor in the percentage of acidity (P > 0.32). No difference in fruit weight (P > 0.07) and ripening grade (P > 0.17) were observed among plants retaining different number of leaves. The results suggest that in tropical commercial banana plantations, producing for international markets, it is possible to defoliate the banana plants to seven leaves at flowering without causing a reduction on the green and yellow life and quality of fruit. 相似文献
117.
M. L. Longo F. M. Vargas Junior K. Cansian M. R. Souza P. C. Burim A. L. A. Silva C. M. Costa L. O. Seno 《Tropical animal health and production》2018,50(7):1493-1497
The main objective of this research was to conduct an exploratory study of the lactation curve in order to characterize the productive potential of Pantaneiro ewes and lambs. Fifty ewes were bred using four rams in two different mating seasons. The ewes were kept with their lambs on pasture of Brachiaria brizantha. Ewe body score, ewe weight, and lamb weight were evaluated. Milk sampling was performed every week. In the morning for milk collections, the ewes were treated with 1 UI of oxytocin (intramuscular) for complete milking. Lambs were separated from the ewes for 4 h and milk collections were performed. The total milk production over 24 h was estimated by multiplying the production of this period (4 h) by 6. The data were analyzed using the MIXED procedure (P?<?0.05) in SAS. Milk production data were fitted to the curve using the incomplete gamma function of Wood, and lamb growth data were fitted using the Gompertiz equation. The average milk production of the ewes was 1.03 kg/day?1. Younger ewes had the lowest milk production (18?=?798?±?330, 24?=?1001?±?440, 36?=?1100?±?490, and 48?=?1106?±?490 g/day?1). Ewe body score at lambing affected initial milk production (1.0?=?816?±?660, 1.5?=?1089?±?105, and 2.0?=?1424?±?1600 g/day?1). Lambs were weaned with an average weight of 20.3 kg. Daily weight gain from birth to weaning was 181 g. Locally adapted Pantaneiro ewes showed a linear decreasing lactation curve, with reduced production from the second week of lactation. Overall, evaluation of the dairy production and lamb performance revealed great variation, denoting potential for selection. 相似文献
118.
Effect of marine by‐product meals on hen egg production parameters,yolk lipid composition and sensory quality
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E. Toyes‐Vargas R. Ortega‐Pérez J. L. Espinoza‐Villavicencio M. Arellano‐Pérez R. Civera E. Palacios 《Journal of animal physiology and animal nutrition》2018,102(2):462-473
The effect of including 5% marine by‐product meals in feeds of laying hens on egg production, composition and sensory characteristics was tested. Marine by‐product meals were prepared using two methods: (i) cooking (100°C/10 min) followed by drying (60°C/24 hr) or (ii) grinding followed by drying. The raw materials used for meal production were scallop or squid viscera, shrimp heads or whole mackerel. A total of 108 laying hens were allocated to nine diet treatments; one control diet (corn and soya bean based) and eight experimental diets, containing 95% of the control feed and 5% of the experimental meal for three weeks. Daily intake was higher in hens fed the dried mackerel and cooked shrimp meals. All the experimental treatments showed significantly higher concentration of n‐3 HUFA in yolk reserves and phospholipids compared to the control (0.12–0.13 g per 100 g), especially those with scallop or squid prepared by both methods (0.53–0.95 g per 100 g). Scallop, squid and shrimp meal inclusion in the feed produced eggs with more astaxanthin (0.22 mg per 100 g) while this carotenoid was absent in the control and mackerel treatments. Visual evaluation of raw yolk colour increased with the inclusion of marine by‐product meals with higher values in hens fed shrimp heads (13), followed by scallop viscera (11), squid viscera (9), and with similar values for mackerel and control (4). The taste, aroma, texture and colour of cooked eggs from different treatments were not statically different when evaluated by a panel of 60 untrained people. These results suggest that meals from marine by‐products are a better alternative for improving egg yolk composition by increasing n‐3 HUFA when compared to fishmeal as they also increase astaxanthin and yolk pigmentation without affecting egg sensory characteristics. 相似文献
119.
120.
Study of the effect of genotype–environment interaction on age at first calving and production traits in Nellore cattle using multi‐trait reaction norms and Bayesian inference
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Francisco Ribeiro de Araujo Neto Newton Tamassia Pegolo Rusbel Raul Aspilcueta‐Borquis Matilde Conceição Pessoa Alexandre Bonifácio Raysildo Barbosa Lobo Henrique Nunes de Oliveira 《Animal Science Journal》2018,89(7):939-945
This study investigated the effects of genotype–environment interaction on yearling weight, age at first calving and post‐weaning weight gain in Nellore cattle using multi‐trait reaction norm models. The environmental gradient was defined as a function of the mean yearling weight of the contemporary groups. A first‐order random regression sire model with four classes of residual variance was used in the analyses and Bayesian methods were applied to estimate the (co)variance components. The heritability estimates ranged from 0.284 to 0.547, 0.222 to 0.316 and 0.256 to 0.522 for yearling weight, age at first calving and post‐weaning weight gain, respectively. The lowest genetic correlations between environment groups for each trait were 0.38, 0.02 and 0.04 for yearling weight, age at first calving and post‐weaning weight gain, respectively. Differences in the correlation estimates were observed between traits in the same environments, with the magnitude of the estimates tending toward zero as the environment improved. The results highlight the importance of including genotype–environment interactions in genetic evaluation programs considering the differences observed between environmental groups not only in terms of heritability, but also of genetic correlations. 相似文献