Navegando por Orientadores "VALE, William Gomes"

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Acesso aberto (Open Access)
Avaliação de diferentes diluentes na criopreservação de sêmen ovino (Ovis aries)
(Universidade Federal do Pará, 2010-08-31) GUIMARÃES, Adrianne Araújo; VALE, William Gomes; http://lattes.cnpq.br/7486151987920142
During cryopreservation are numerous changes experienced by the sperm cells, which leads to the decrease in motility and loss of viability after thawing. For this reason, there arises the need to refine the process technology of semen, especially regarding the use of diluents. The aim of this study was to evaluate the viability of spermatozoa undergoing the process of cryopreservation and dilution, using three extenders (TES, TRIS and PBS) and three years of stability (4h, 8h and 12h), and the study was divided into nine groups: TES-4h-8h TES, TES- 12h, TRIS-4h-8h TRIS, TRIS-12h-4h PBS, PBS and PBS-8h-12h. After collection, semen was evaluated macro and microscopically, and pre-diluted solutions in TES, TRIS and PBS, but without the addition of cryoprotectants (Solution A), where they remained for 1 hour. Subsequently, semen was diluted with solutions TES, TRIS and PBS, already containing the cryoprotectants, again assessed to be so packed, and subjected to different periods of equilibrium, and then frozen. After thawing, motility was assessed and vigor, and after the TTR, motility, vigor and detachment of the acrosome. On cryopreservation with TRIS, motility and vigor were statistically similar (p> 0.05) in semen frozen with a balance of 4h (17.2% and 1.6), 8h (22.4% and 2.1) and 12h (14.8% and 1.6) (p> 0.05). After the TTR was not observed statistical difference (p> 0.05) in motility and vigor in 4h (10.4% and 1.1) and 12h (10.0% and 1.2) of balance, but there was an increase in 8h (15.6% and 1.6) (p <0.05). There was no statistical difference (p> 0.05) in the rate of detachment of the acrosome between 4h (35.1) and 12 (37.6) equilibrium, with a reduction in these indices at 8 am (30.4) (p <0 , 2005). On cryopreservation with ERT, the motility of frozen semen with a balance of 4h (24.8%) and 12h (27.6%) were statistically similar (p> 0.05), although the time of 8h (40.4% ) differed significantly from the others. The force was statistically similar (p> 0.05) for thawed-balanced 4h (2.0), 8h (2.6) and 12h (2.3), not statistically different (p> 0.05) . After the TTR was not observed statistical difference (p> 0.05) for sperm motility in 4h (18.8%) and 12h (17.4%) of balance, but there was an increase in 8h (29.6%) (p <0.05). In relation to the force and the detachment of the acrosome was no statistical difference (p> 0.05) 4h (2.0 and 35.8), 8h (2.1 and 33.4) and 12h (1.8 and 42 , 2) equilibrium. On cryopreservation with PBS, showed no motility and vigor after thawing. These results indicate that solvent-based TES and the equilibrium time of 8h were more suitable for dilution and freezing of ram semen.
Acesso aberto (Open Access)
Comparação entre o TRIS, Lactose/TRIS, Ringer-Lactato e Leite Desnatado como diluidores na criopreservação do sêmen bubalino
(Universidade Federal do Pará, 2012-02-29) MIYASAKI, Michel Yoshio Almeida; VALE, William Gomes; http://lattes.cnpq.br/7486151987920142
The objective of this experiment was to test the effectiveness of different extenders, the basis of Ringer Lactate, Skim Milk, TRIS (hydroxymethyl-amino-methil Methan) and Lactose/TRIS, the cryopreservation of buffalo semen. We used three male Murrah buffaloes in full sexual activity. The semen was collected by artificial vagina total of 71 ejaculates. After harvest, each sample was subjected to qualitative and quantitative analyzes of semen. The ejaculates were split and diluted in four extenders. The diluted semen was stored in straws of 0,25 mL and subjected to an equilibration time of up to four hours at 5°C, with subsequent freezing in liquid nitrogen. The identified samples were thawed in a water bath at a temperature of 40°C for 30 seconds and subsequently evaluated for motility, vigor, acrosome damage, and percentage of sperm pathologies. The samples were also tested with heat-resistance, while remaining incubated at 40°C for 30 seconds, 3-5 minutes, 30 minutes, 1 hour, 2 hours and 3 hours, which were evaluated for motility and spermatic . The physico-chemical, after fresh semen analysis, were within the prescribed values for buffaloes and satisfactory for the freezing process. After thawing the semen, observed numerical reduction (p<0,05) in sperm motility, with fresh semen was found 86,67±6,17% decreasing to 70±6,92% in TRIS, 67,4±8,01% in Ringer/lactate, 67,09±9,03% in Lactose/TRIS and 59,7±9,05% in skim milk and to compare between the four treatments only the skimmed milk showed a statistically significant difference (p<0,05). After thawing, spermatic vigor also decreased significantly (p<0,05) in four treatments (3,50±0,53 TRIS, 3,38±0,49 Ringer's lactate, 3,3±0,46 Lactose/TRIS and 3,25±0,44 Skim milk) versus (4±0,39 fresh semen) and when comparing between treatment, only between skimmed milk and TRIS was no statistical difference (p<0,05). As for the larger defects (4,15±1,9% fresh semen; 10,51±4,4% TRIS, 11,94±4,2% Ringer's lactate, 11,88±4,8% Lactose/TRIS; 12,01±5% skim milk), smaller (3,81±1,2% fresh semen and 4,67±1,1% TRIS, 4,98±1,7% Ringer's lactate, 4,93±2,0% Lactose/TRIS, 4,93±2,0% skimmed milk) and total (7,91±2,1% fresh semen; 15,18±4,7% TRIS, 16,92±4,8% Ringer's lactate, 16,82±5,6% Lactose/TRIS, 17,11±5,6% skimmed milk), after thawing showed a significant increase of defects in the four treatments (p<0,05), and among them were not statistically different between groups (p>0,05). In the post-TTR after 3 hours of incubation, progressive motility (21,13±7,5% TRIS; Ringer lactate 20,78±7,4%; Lactose/TRIS 20,25±5,3%; Skimmed milk 20,12±6,6%) and spermatic vigor (TRIS 2,04±0,5, Ringer Lactate 2,07±0,5, Lactose/TRIS 2,02±0,4, 2 skim milk, 2,00±0,5) showed no statistical difference between treatments (p<0,05). As for intergridade acrosome after thawing (semen in natura 97,85,±0,6%; TRIS 91,65±4,3%, Ringer-Lactate 90,46±4,8%; Lactose/TRIS 89,76±5,4%; Skimmed milk 90,56±5,6%), decreased (p<0,05) and when comparing this parameter between treatments was not observed statistically significant differences between the treatment (p>0,05). Given the observed results we conclude that the freezing of buffalo semen extenders with TRIS (Tris-hydroxy-methyl-amino-Methan), Ringer Lactate, Lactose / TRIS and skimmed milk showed satisfactory function in cryoprotection of sperm viability semen in different stages of cryopreservation.
Acesso aberto (Open Access)
Emprego do cloridrato de xilazina e do maleato de acepromazina na exteriorização do pênis de búfalos (Bubalus bubalis, Lin.)
(Universidade Federal do Pará, 2004) BITTENCOURT, Ruth Helena Falesi Palha de Moraes; VALE, William Gomes; http://lattes.cnpq.br/7486151987920142
Acesso aberto (Open Access)
Utilização de derivado progesterônico na sincronização do ciclo estral em fêmeas bovinas e bubalinas utilizadas na inseminação artificial em tempo fixo (IATF)
(Universidade Federal do Pará, 2012-05-03) NOGUERA GUEVARA, Samuel Enrique; VALE, William Gomes; http://lattes.cnpq.br/7486151987920142
The use of intravaginal devices with progestin as protocol for synchronization of oestrus cycle for fixed time artificial insemination (FTAI) through “Pregna Heat - E'' protocol were used in 219 cows and 169 female buffaloes, belonging to six commercial farms located in the Tachira, Carabobo, and Portuguesa states, in the Bolivarian Republic of Venezuela with the aim to evaluate conception rates (CR) in beef cows and crossbred dairy cattle, milk buffalo and crossbred dairy cows, and crossbred beef and milk heifer as well as in milk buffalo heifers as well as, with the objective to evaluate several variables that can interfere with CR such as body condition score (BCS), number of births, birth interval treatment, degree of difficulty for AI in the farms in the Farm 1, whereas in other farms were evaluated only the CR. The farms adopted a semi-intensive management, with a diet based primarily on forage species introduced in a artificial pasture used in a rotational grazing system with supplementation on the field depending on the needs of each production system. On a Farm 1, located just south of Lake Maracaibo, Tachira State, were synchronized and subjected to FTAI, 22 crossbred dairy cattle heifers, 20 crossbred dairy cows in the postpartum period (PPP) and 18 crossbred buffalo dairy heifers inseminated when 27.2%, 30% and 0 (zero) CR were obtained; moreover in 24 buffalo cows in the PPP synchronized in the outbreeding season (February 2011), it was obtained a CR of 20.8%. For the Farm 2, located in the southern state Tachira, FTAI was performed in favorable season (November 2010) in 78 crossbred dairy buffalo cows in PPP it was obtaining a CR of 34.6%. In the case of Farm 3, located in Urama county in Carabobo State, 49 crossbred buffalo cows in the PPP, were subjected to FTAI when it was obtaining a CR of 42.8%; in Farm 4, located in Santa Ana county, Tachira state, 85 crossbred dairy cattle cows were used for FTAI with 40% CR obtained, whereas in Farm 5, located in Portuguesa state, 23 crossbred beef cows of dual purpose in PPP were subjected to FTAI and it was found47.8% CR; finally in the Farm 6 located in Portuguesa State 20 crossbred beef heifers and 49 crossbred beef cow, were subjected to FTAI were found a CR of 55 and 48.8%, respectively. Also on Farm 1 were compared variables such as CR and number of births, when it was clear demonstrated that CR in pluriparous beef cows with more than four parturitions the results obtained where quite higher when confronted with cows with 2-3 parturitions and primiparous (40.5 ≥ 4 births, 28.5% 2-3 births and 0% for primiparous), (P = 0.4130); when compared with CR and parturition interval and the use of FTAI protocol “Pregna Heat - E'', the CR is higher in cows between 60 and 200 days postpartum, than cows with the interval of more than 200 days, which showed a very low CR (9.0%) (P = 0.0241); regarding to ECC no significant statistical difference important were observed among females with BSC=3 submitted to FTAI when confronted to animals with higher BCS. In the case of Farm 3, located in Urama county in Carabobo State, 49 crossbred buffalo cows in the PPP, were subjected to FTAI obtaining a CR of 42.8%, whereas in Farm 4, located in Santa Ana county, Táchira state, 85 crossbred dairy cattle cows was used for FTAI, 40% CR obtained, and in Farm 5, located in Portuguesa state, where 23 crossbred beef cows of dual purpose in PPP subjected to FTAI, it was found 47.8% CR; finally in the Farm 6 located in Portuguesa State 20 crossbred beef heifers and 49 crossbred beef cow, were subjected to FTAI when was found a CR of 55 and 48.8%, respectively. Still in the Farm 1 were compared variables such as CR and number of births, when it was clear demonstrated that CR in pluriparous beef cows with more than four parturitions where quite higher when confronted with cows with 2-3 parturitions and primiparous (40.5 ≥ 4 births, 28.5% 2-3 births and 0% for primiparous), (P = 0.4130); when compared with CR and parturition interval and the use of FTAI protocol “Heat-pregna - E'' the CR is higher in cows between 60 and 200 days postpartum, than cows with the interval of more than 200 days, which showed a very low CR (9.0%) (P = 0.0241); regarding to ECC no significant statistical difference important were observed among females with BSC=3 submitted to FTAI when confronted to animals with higher BCS showing a very poor (P=0.1632). With reference to the degree of difficulty for AI, animals with 0 degree of difficulty for AI, presenting the highest conception rates compared to the animals of 1 degree (44.4 and 31.2%), respectively. The use of the protocol “Pregna Heat - E” for FTAI, can be recommended for both in cattle and buffaloes with satisfactory results, however the CR in the case of crossbred Bos taurus or crossed animals with more blood of this sub-species probably due the fact that are raised in hot and humid regions as in the case of Farm 1, it has been observed a decrease in CR, which can be attributed to environmental factors interfering negatively on this variable. Likewise it is important to note that female buffaloes must be synchronized at the favorable season, not in outbreeding season, since throughout this time there was a decrease in CR in buffaloes submitted to FTAI, 20.8 vs 34.6% and 42.8%, respectively. In the case of the use of synchronization protocols such as “Pregna Heat – E” for FTAI use in buffalo heifers in the present study showed to be inadequate, with zero of CR, probably due anatomical and physiological concerned to the reproductive tract (very small cervix), thus buffalo heifers should not be included in FTAI programs with conventional techniques. The protocol ''Pregna Heat - E” can be used as a viable tool for oestrus cycle synchronization and FTAI in both cattle and buffaloes, and in the present study with the bovine CR being higher than in buffaloes (40.1 vs 31, 9%) (Fisher = 0.9624, P = 0.0212, P <0.05). That being so the use of “Pregna Heat - E” protocol as was used in the present study needs to be further studied in buffalo to obtain higher conception rates.