F. Z. Brandão

Efeito da base genética materna e da estação de parição sobre variáveis produtivas de fêmeas primíparas Holandês x Zebu

Productive variables of 78 crossbred Holstein x Zebu primiparous cows of Gir or Guzera maternal genetic basis, calved in the dry or rainy season were evaluated using the GLM procedure of the SAS. The calving season affected the weight at calving (WC), body condition score at calving (BCS), service period (SP) and calving interval (CI). The WC and BCS were higher (P<0.05) por cows calved in the dry season, 475.19±39.81kg and 4.07±0.44, than in the rainy season, 420.67±37.80kg and 3.62±0.37, respectively. The SP and CI were shorter (P<0.05) for cows calved in the dry season, 132.02±91.94 days and 13.90±3.06 months, than cows calved in the rainy season, 190.07±77.27 days e 15.84±2.58 months, respectively. The Gir based cows had higher milk yield, longer lactation period and higher milk yield per day of calving interval than the Guzera based cows, respectively, 2276.15±656.47kg, 306.08±46.55 days, 5.06±1.38kg/day for the Gir and 1733.74±678.41kg, 265.62±67.11 days, 4.37±1.68kg/day for the Guzera based cows.

Influência da presença do bezerro no momento da ordenha sobre o desempenho reprodutivo de vacas mestiças Holandês-Zebu

This study was carried out to evaluate the effect of calf presence in the milking parlour on the reproductive performance of seventy five crossbred (Holstein × Zebu) cows randomly allocated into three groups: group I - cows milked without the calf presence; group II - cows mantained with their calves during short period of time before milking to promote milk ejection and thereafter the calves were put out the milking room until the cows had finished milking; and group III - cows mantained with the calf during milking. The average body condition score at calving was 3.1. The service period, number of days to return to estrous and estrous and pregnant rates until 120 day postpartum were not influenced (P>0.05) by milking management of cows. The calf presence in the milking parlour did not influence the reproductive performance of Holandes-Zebu crossbred cows.

Indução do estro no pós-parto em vacas primíparas Holandês-Zebu

The experiment was carried out to evaluate the effect of two ranges of body weight and norgestomet treatment on the reproductive parameters of postpartum crossbred Holstein-zebu cows. Sixty four primiparous cows were randomly allocated to four treatments 40 days after calving: group I - cows with body weight ranging from 390 to 458kg and norgestomet treated; group II - cows with body weight ranging from 464 to 562kg and norgestomet treated; group III - cows with body weight ranging from 390 to 458kg (control); and group IV - cows with body weight ranging from 464 to 562kg (control). Progestagen auricular implants were mantained during 10 days and the cows were mated to bulls submitted to breeding soundness evaluation. Animals from treatment II showed estrus earlier than animals of the others treatments (II: 64.4; I: 109.4; III: 143.2 and IV: 105.1 days; P 0.05). The hormonal treatment and the body weight did not affect the total and daily milk yield, and length of lactation (P>0.05). Progestagen treated, heavier and better body condition scored animals had shorter open days, and returned to postpartum ovarian ciclicity faster than lighter animals.

Freezing goat embryos at different developmental stages and quality using ethylene glycol and a slow cooling rate.

Abstract: The efficiency of an alternative freezing protocol for goat embryos of different morphology and quality was tested. Fifty-eight embryos on Day 6-7 stage were transferred as fresh or after freeze-thawing (n=29/group). For freezing, embryos were placed into 1.5M ethylene-glycol solution for 10min. During this time, they were loaded in the central part of 0.25mL straw, separated by air bubble from columns containing PBS/BSA 0.4% plus 20% BFS. Straws were then frozen using a freezing machine from 20oC to ?6oC at a cooling rate of 3oC/min, stabilization for 15min (seeding after 5min), from ?6 C to ?32oC at 0.6 C/min,and plunged into liquid nitrogen. Frozen embryos were thawed for 30s at 37oC in a water bath. Embryos subjected to fresh transfer were maintained in holding medium (37oC). Fresh and frozen-thawed embryos were transferred at day 7 post-estrus to 30 recipients. Kidding and kid born rates were similar (P> 0.05), respectively, for recipients receiving fresh (66.7% or 10/15; 55.2% or 16/29) or frozen-thawed (60% or 9/15; 51.7% or 15/29) embryos. The cryopreservation of goat embryos using slow-freezing protocol and 1.5MEG resulted in similar efficiency rates of fresh embryos. [Congelacao de embrioes caprinos em diferentes estadios de desenvolvimento e qualidade utilizando etileno glicol e taxa de resfriamento lenta]. Resumo: Este estudo testou a eficiencia de protocolo alternativo de criopreservacao de embrioes caprinos de diferentes qualidades morfologicas. Foram utilizados 58 embrioes, coletados entre o sexto e o setimo dia do ciclo estral (n=29/grupo). Embrioes congelados passaram por solucao 1,5M etilenoglicol por 10min e foram aspirados durante esse tempo para parte central de palheta 0,25mL, separada por bolhas de ar de colunas contendo PBS 0,4% BSA e 20% SFB. As palhetas foram congeladas em maquina de congelacao de 20oC a -6oC, com taxa de resfriamento de 3oC/min, estabilizacao por 15min (seeding apos 5min), -6oC a -32oC a 0,6oC/min, e imersas em nitrogenio liquido. Os embrioes foram descongelados por 30s a 37oC, em agua. Embrioes frescos foram mantidos em solucao de manutencao (37oC). Embrioes frescos e congelados/descongelados foram transferidos para 30 receptoras no setimo dia do ciclo estral. A taxa de partos e a de crias nascidas (respectivamente) foram similares (P>0,05) para receptoras recebendo embrioes frescos (66,7% ou 10/15; 55,2% ou 16/29) ou congelados/descongelados (60,0% ou 9/15; 51,7% ou 15/29). O protocolo de criopreservacao de embrioes utilizado no presente estudo resultou em indices de eficiencia semelhantes aos de embrioes frescos.

Parâmetros reprodutivos após indução de estro com diferentes intervalos de permanência do dispositivo vaginal em cabras Toggenburg acíclicas.

Resumo: Este estudo objetivou avaliar o comportamento sexual e a dinâmica ovulatoria de cabras da raca Toggenburg apos a inducao do estro com dispositivo intravaginal de progesterona durante seis, nove e 12 dias de permanencia. No momento da insercao do dispositivo e 24 horas antes da retirada do dispositivo, foi administrado 5mg de dinoprost e 200UI de eCG, respectivamente. A dinâmica ovulatoria foi acompanhada por ultrassonografia a cada oito horas, enquanto o estro foi observado a cada 12 horas. Todas as cabras apresentaram estro. O intervalo da retirada do dispositivo ao inicio do estro foi de 29,5 ± 9,6 para G6dias; 34,0 ± 6,0 e 32,4 ± 7,7h, G9dias e G12dias, respectivamente. Igualmente, foi encontrada diferenca (P 0,05). Todos os protocolos foram eficientes em induzir o estro sincronizado em cabras da raca Toggenburg, trabalhando em conjunto com a eficiencia reprodutiva e produtiva desses animais. [Reproductive parameters after induction of estrus with different ranges of the vaginal device in acyclic Toggenburg goats]. Abstract: This study aimed to evaluate the sexual behavior and the ovulatory dynamics of Toggenburg goats after induction of synchronized estrus by an intravaginal progesterone device for six, nine and twelve days. At the device insertion and 24 h before the device removal, 5mg of dinoprost and 200 UI of eCG was administered, respectively. The ovulatory dynamics was assessed by ultrasound every 8 h, while the sexual behavior was observed every 12 h. All goats showed estrus. The intervals from device removal to estrus were 29.5 ± 9.7, 34.0 ± 6.0 and 32.4 ± 7.7h to G6days, G9days and G12days, respectively. Iqually, it was found difference (P 0.05). All treatments were effective for the induction of synchronized estrus in Toggenburg goats, working jointly with the reproductive and productive efficiency of these animals.