Avaliação on-farm dos níveis de energia na dieta sobre a produção e a composição físico-química de leite de cabras / [On farm evaluation of the energy levels in the diet on the production and physical-chemical composition of dairy goats]

Objetivou-se, com este estudo, avaliar o efeito de dietas com diferentes níveis de energia no consumo de nutrientes, na produção e na composição do leite, no peso corporal e na relação benefício:custo de uma produção de cabras leiteiras. Foram utilizadas nove cabras, distribuídas em quadrado latino triplo 3 x 3. O ensaio teve duração de 60 dias, divididos em três períodos de 20 dias. Avaliaram-se rações completas contendo três níveis de energia: 65%, 70% e 75% de NDT. Os consumos de matéria seca, proteína bruta e matéria mineral foram superiores (P<0,05) nas dietas com maiores níveis de energia em comparação à dieta com 65% de NDT. A produção de leite foi semelhante (P>0,05) nas cabras recebendo dietas contendo 70% e 75% de NDT, todavia foi superior (P<0,05) à produção de leite das cabras recebendo dieta com 65% de NDT. A dieta com 75% de NDT possibilitou maior (P<0,05) peso corporal final, quando comparada com as dietas contendo 65% e 70% de NDT. Não foi observada diferença (P>0,05) para os parâmetros físico-químicos de gordura, lactose, proteína bruta, extrato seco desengordurado, densidade, sais e condutividade do leite. Portanto, cabras alimentadas com níveis de energia entre 70% e 75% de NDT na dieta total aumentam a produção de leite, porém 75% de NDT na dieta proporciona melhor relação benefício:custo, havendo, para cada R$ 1,00 no custo investido na alimentação, R$ 1,52 de retorno financeiro.(AU)

The objective of this study was to evaluate the effect of diets with different energy levels on nutrient intake, milk production and composition, body weight and benefit:cost ratio of a dairy goat production. Nine goats were distributed in a triple 3 x 3 latin square design. The experiment lasted for 60 days, divided into three 20-day periods. Complete rations containing three energy levels were evaluated: 65%, 70% and 75% of TDN. The dry matter intake, crude protein and mineral matter consumption were higher (P <0.05) in the diets with higher levels of energy compared to the diet with 65% of TDN. Milk production was similar (P> 0.05) in goats receiving diets containing 70% and 75% TDN, but these diets produced more milk (P<0.05) than the diet with 65% of TDN. The diet with 75% of TDN allowed a higher (P<0.05) final body weight (P<0.05) when compared to diets containing 65% and 70% TDN. There was no difference (P> 0.05) in the physical-chemical parameters of fat, lactose, crude protein, defatted dry extract, density, salts and conductivity of the milk. Therefore, goats fed with diets of 70% and 75% of TDN in the total diet increased milk production. However, the diet with 75% of TDN provides a better benefit:cost ratio, as for every $ 1.00 in the cost invested, there was $ 1.52 of financial return.(AU)

Efeito da somatotropina bovina recombinante (rbST) na produção in vivo e na maturação in vitro de oócitos bovinos da raça Sindi / Effect of recombinant bovine somatotropin (rbST) on the in vivo production and in vitro maturation of bovine oocytes of the Sindi breed

A fim de avaliar o efeito de diferentes doses da rbST sobre a dinâmica folicular, a produção e a maturação in vitro de oócitos, 20 vacas Sindi, divididas em três grupos, receberam um dispositivo de progesterona intravaginal, estradiol e PGF2α, além de 2mL de solução salina (grupo controle), 250 (grupo rbST 250) ou 500mg de rbST (grupo rbST 500). Cinco dias depois, realizou-se a ovum pick up, e os complexos cumulus-oócitos (CCOs) recuperados foram selecionados, classificados e maturados in vitro. Os dados de contagem foram comparados pelo procedimento glht (General Linear Hypothesis Test), e os dados em porcentagem foram submetidos ao qui-quadrado, no programa estatístico R, onde as diferenças foram consideradas significativas quando P<0,05. Não houve diferença (P>0,05) entre os grupos quanto à quantidade de folículos e à taxa de maturação. Os grupos rbST 250 e rbST 500 foram significativamente superiores (P<0,05) ao grupo controle em relação ao número de folículos grandes (0,42±0,20 vs. 0). O grupo rbST 500 apresentou maior (P<0,05) porcentagem de oócitos viáveis (91,52%) do que os grupos controle (67,85%) e rbST 250 (53,33%). A rbST aumenta o número de folículos grandes, e 500mg de rbST aumentam a porcentagem de oócitos viáveis em vacas Sindi.(AU)

In order to evaluate the effect of different doses of rbST on the follicular dynamics, production, and in vitro maturation of oocytes, 20 Sindhi cows were divided into three groups, receiving an intravaginal progesterone device, estradiol and PGF2α, and 2mL of solution saline (Control Group), 250 (rbST 250 Group) or 500mg rbST (rbST 500 Group). Five days later, the ovum pick up was performed, and the cumulus-oocyte (CCO) complexes recovered were selected, classified, and matured in vitro. The counting data were compared by the glht (General Linear Hypothesis Test) procedure, and the percentage data were submitted to Qui- square, in the statistical program R, where differences were considered significant when P< 0.05. There was no difference (P> 0.05) between the groups regarding follicle quantity and maturation rate. The rbST 250 and rbST 500 groups were significantly higher (P< 0.05) than the Control group in relation to the number of large follicles (0.42±0.20 versus 0). The rbST 500 group presented higher (P< 0.05) percentage of viable oocytes (91.52%) than the Control (67.85%) and rbST 250 (53.33%) groups. rbST increases the number of large follicles and 500mg rbST increases the percentage of viable oocytes in Sindhi cows.(AU)

Efeito do óleo essencial do Croton nepetifolius Baill na penetração cervical em ovelhas mestiças de Dorper e Santa Inês / Effect of the essential oil of Croton nepetifolius Baill on cervical penetration in crossbred Dorper and Santa Inês ewes

A fim de se avaliar o uso do óleo essencial de Croton nepetifolius Baill (OECn) na penetrabilidade cervical em ovelhas mestiças, 40 ovelhas foram distribuídas ao acaso em quatro grupos (n=10): controle, misoprostol, OECn50 e OECn100 (50 e 100µg do OECn, respectivamente). Após a sincronização do estro, utilizando CIDR e eCG (200UI), a profundidade de penetração da cérvix foi mensurada utilizando-se uma pipeta de inseminação artificial de bovino graduada, no período de zero até 72h após a retirada do CIDR. Os resultados foram expressos em média ± erro-padrão, submetidos à ANOVA seguida do teste de Tukey, enquanto os dados, em porcentagem, foram submetidos aos testes de Fisher ouqui-quadrado. Nenhuma diferença significativa (P>0,05) foi encontrada quanto ao grau de penetrabilidade cervical. Quanto ao tempo de passagem, os grupos misoprostol e OECn100 apresentaram um menor tempo de penetrabilidade às 60h(1,7±0,6 e 1,5±0,6min, respectivamente), quando comparados ao grupo controle (4,1±0,6min), que não diferiu significativamente do grupo OECn50 (2,3±0,6min). Portanto, o óleo essencial de Croton nepetifolius Baill pode ser utilizado para encurtar o tempo de penetrabilidade cervical em ovelhas submetidas à sincronização estral.(AU)

In order to evaluate the use of the essential oil of Croton nepetifolius Baill (EOCn) on cervical penetration in crossbred ewes, 40 ewes were randomly allocated into four groups (n= 10): CONTROL, MISOPROSTOL, EOCn50 and EOCn100 (50 e 100µg of the EOCn, respectively). After estrus synchronization, using CIDR and eCG (200IU), depth of cervical penetration was measured using artificial insemination gun for bovine species which was graduated and used from 0 to 72h after CIDR removal. Results were expressed as mean ± standard error mean, submitted to ANOVA and Tukey test while data in percentage were submitted to Fisher or Chi-Square test. No significant difference (P> 0.05) was observed at grade of cervical penetration. Concerning trespassing time, MISOPROTOL and EOCn100 groups presented a lower trespassing time at 60h (1.7±0.6 and 1.5±0.6min, respectively) than CONTROL group (4.1±0.6min), which did not differ significantly from EOCn50 (2.3±0.6min) group. Therefore, the essential oil of Croton nepetifolius Baill can be used to shorten the cervical penetration time in estrus synchronized ewes.(AU)

Quercetin influences in vitro maturation, apoptosis and metabolically active mitochondria of goat oocytes.

SummaryThe present study aimed to investigate the effect of quercetin as an alternative antioxidant to cysteamine on in vitro maturation. Oocytes were collected from goat ovaries, destined for in vitro maturation and distributed into three groups: CIS group, oocytes were immersed in MIV base medium; in Groups Q4 and Q8, oocytes were immersed in the medium of the CIS group, adding 4 µM or 8 µM of quercetin, respectively, and cultured for 24 h at 38.5°C with 5% CO2. The CIS and Q4 groups presented the same percentage of expanded cumulus cells, but the per cent in the Q8 group was significantly lower than that of the other groups (P<0.05). The oocyte retraction rate in the Q8 group was higher (P<0.05) than in the CIS and Q4 groups. Treatment with 8 µM of quercetin presented a lower proportion of expanded oocytes than the CIS group and 4 µM of quercetin (P<0.05). The percentage of MII oocytes was higher in the Q4 group than in the CIS group (P<0.05), but the percentages in the CIS and Q8 groups were similar. The rate of apoptosis was higher in the CIS group than in the other groups (P<0.05). In addition, oocytes matured with 4 µM quercetin showed higher mitochondrial activity than matured oocytes in the CIS and Q8 groups (P<0.05). In conclusion, 4 µM of quercetin can be used as an alternative to cysteamine in the in vitro maturation of goat oocytes.

Pronuclear embryo yield in Canindé and Saanen goats for DNA microinjection.

The objective of this study was to examine the effect of donor breed on pronuclear-stage embryo yield to be used for DNA microinjection in a transgenesis goat program. Twelve Canindé and twelve Saanen goats were heat synchronized using a progestagen-cloprostenol treatment. Forty-eight hours before the sponge removal, superovulation was induced with a total administration of 4.4 mg/kg bodyweight NIH-FSH-P1, given twice daily in decreasing doses over 3 days. In addition, goats received 100 µg of GnRH and they were hand-mated at 36 and 48 h after progestagen removal. Embryo recovery was performed by oviduct flushing at 72 h after sponge removal. Embryos were microinjected with a DNA construct and noticeable swelling of the nuclei was the criterion for successful microinjection. The total diameter, cytoplasm diameter, zona pellucida thickness and pronuclei diameter were measured for each microinjected embryo. A higher (p < 0.05) percentage of fertilized ova was observed in Canindé (89.9%) than Saanen (36.2%) goats. In addition, Canindé donors produced a higher percentage of pronuclear embryos when compared with Saanen: 72.5% vs 20.6% (p < 0.05), respectively. Successful microinjection was verified in 96.7% and 73.3% of times in Canindé and Saanen embryos, respectively (p < 0.05). Significant differences were observed for all morphometric parameters except for cytoplasm diameter. In conclusion, under our study experimental conditions, Canindé were more efficient than Saanen goats concerning the pronuclear embryo yield and manipulation. The use of Canindé goats in transgenesis programs could be increase the interest in their breeding and could be contribute to saving them from extinction.

Determination of the genital tubercle migration period in Morada Nova sheep foetuses by ultrasonography.

The aim of this study was to determine the period of genital tubercle (GT) migration using ultrasonography in Morada Nova sheep foetuses (n = 117) from natural mating (NM) and frozen embryo transfer (ET) to determine the window when foetal sexing can be determined. The examinations were performed using transrectal ultrasonography with a dual-frequency linear transducer (6.0 and 8.0 MHz) from day 30-54 of pregnancy at 48-h intervals. The period of GT migration of foetuses produced by NM varied from 36 to 46 days of pregnancy, resulting in an average of 39.5 +/- 2.9 days. For foetuses derived from ET, GT migration varied from 42 to 52 days of pregnancy with an average of 48.5 +/- 3.3 days, being possible the GT of foetuses from ET start to migrate 96 h later even if they are of the same gender. Migration of the GT occurred earlier (p < 0.05) in foetuses produced by NM and sexing accuracy for triplet pregnancies (77.8%) was significantly inferior (p < 0.05) to single (100%) and twin (92.9%) pregnancies for foetuses derived by NM. The results allow one to conclude that foetal sexing can be done from the 50th day onwards in foetuses produced by NM and from the 55th day onwards in foetuses derived from ET, and that multiple pregnancies compromise the sexing accuracy by ultrasonography.

Effect of age of donor on embryo production in Morada Nova (white variety) ewes participating in a conservation programme in Brazil.

In order to evaluate embryo production in Morada Nova (white variety) ewes superovulated with porcine follicle-stimulating hormone, 20 cycling ewes were used as embryo donors and allocated into two groups according to age: group 1 (ewes aged 1-2 years; n = 9) or group 2 (ewes aged 3-4 years; n = 11). Embryo recovery was performed by laparotomy 5-6 days after oestrus. The evaluation of embryos was made under stereomicroscope according to International Embryo Transfer Society rules. The overall recovery rate was 64.6% (5.0 +/- 0.7 structures per ewe) and 86.3% of the recovered structures were fertilized. Group 1 was superior (p < 0.05) to group 2 according to recovered (6.6 +/- 0.9 vs 3.6 +/- 0.8) and fertilized structures (5.6 +/- 1.1 vs. 3.5 +/- 0.7) per ewe. In conclusion, the ovarian response and the embryo production in Morada Nova (white variety) sheep subjected to a standard superovulation treatment were considered satisfactory. In addition, the use of multiple ovulation and embryo transfer in younger ewes ( < or = 2 years old) of this sheep breed appears to be an efficient tool to accelerate the preservation of the Morada Nova (white variety) breed, since younger ewes are as responsive as older ones.

Responsiveness to progestagen-eCG-cloprostenol treatment in goat food restricted for long period and refed.

For 6 months, 10 adult Saanen crossbred goats were fed undernutrition diet (70% maintenance), and finally five goats were refed for 6 weeks with 150% maintenance. In all animals oestrus was synchronized using 45 mg FGA vaginal sponge for 11 days, 300 IU eCG and 50 microg cloprostenol 48 h prior to sponge removal. From oestrus onset, during a 24-h period, blood samples were collected for oestradiol and NEFA assay. Ovulation was verified by laparoscopy 3 days after sponge removal. Body mass loss was 18.62 +/- 3.03% of initial weight and in refed goats body weight recovery was 90.63 +/- 3.56%. NEFA level was higher in restricted goats (p < 0.05). Fifty per cent of underfed goats (2/4) and all refed goats (4/4) exhibited oestrus and ovulation. Significant relationship (p < 0.05) was found between weight loss and the interval sponge removal-oestrus onset (r = 0.91) or ovulation rate (r = 0.70). Only in the refed group was the ovulation rate related to the oestradiol amount (r = 0.99) (p < 0.05). Collectively results showed that a short period of improved feeding re-established the responsiveness of oestrus synchronization in chronically fasted goats.

Pseudopregnancy in Saanen goats (Capra hircus) raised in Northeast Brazil.

The prevalence of pseudopregnancy over 44 months was investigated in 23 Saanen goats raised in Northeast Brazil during continuous oestrous cycling (cyclic group) or after synchronization of oestrus (synchronized group). The goats were monitored by ultrasonography and their plasma progesterone profile. The overall prevalence of pseudopregnancy was 30.4% (7/23). In the cyclic group, 28.6% (4/14) of goats showed pseudopregnancy, while in the synchronized group the prevalence was 33.3% (3/9). There was no significant difference between the groups (p>0.05). The mean (+/- SD) length of pseudopregnancy, as shown by the progesterone profile, was 121.6 +/- 33.5 days, ranging from 70 to 155 days. The study defined the prevalence of pseudopregnancy in Saanen goats raised in Northeast Brazil for the first time. This finding identified a major problem for this breed, as without treatment such animals remain unproductive until the spontaneous resolution of the condition. More research seems desirable to ascertain the prevalence of this condition in other breeds in this region of Brazil.

Sincronizaçäo do estro, induçäo da ovulaçäo e fertilidade de ovelhas deslanadas após tratamento hormonal com gonadotrofina coriônica eqüina / Estrus synchronization, ovulation induction and fertility in hairless ewes treated with equine chorionic gonadotrophin

Utilizou-se a sincronizaçäo do estro com esponjas vaginais de 30mg de acetato de fluorogestona durante 12 dias para avaliar o efeito de diferentes doses de eCG sobre o desempenho reprodutivo de ovelhas. Na retirada das esponjas as ovelhas foram divididas em três grupos para receberem 0 (n=26), 200 (n=30) ou 400UI (n=30) de eCG. O estro foi detectado a cada 12h utilizando-se um rufiäo. As fêmeas foram inseminadas por laparoscopia 60h após a retirada das esponjas. Realizaram-se colheitas de sangue aos 5 e 18 dias pós-inseminaçäo para dosagem de progesterona e determinaçäo do número de ovulaçöes e prenhezes, respectivamente. A fertilidade foi verificada por ecografia aos 60 dias e ao parto. Das 86 ovelhas 70,9 por cento apresentaram estro. Essa porcentagem foi maior (P<0,05) nas fêmeas tratadas com eCG: 96,7 por cento (400UI) e 76,7 por cento (200UI) versus 34,6 por cento (0 UI). O intervalo entre o final do tratamento e o início do estro foi maior (P<0,05) no grupo sem eCG, 54,7 +/- 6,3h versus 45,9 +/- 7,8h para 200UI e 40,4 +/- 10,3h para 400UI. Verificou-se menor (P<0,05) número de ovulaçöes e prenhezes no grupo sem eCG. A näo aplicaçäo de eCG influiu negativamente no desempenho reprodutivo de ovelhas deslanadas