RESUMO
Information on weaning techniques in the tropics is scarce, particularly regarding the long-term effect of temporary early cow-calf separation or restricted suckling. Therefore, we studied the effects of these two handling practices on well-being and performance at 150â¯days postpartum in fifteen zebu cow-calf pairs randomly assigned to three treatments. Continuous suckling (CS) where calves remained with their dams from birth to weaning; restricted suckling (RS) calves were allowed to suckle 30â¯min/day from Day 34 until weaning at Day 150 and kept separated the rest of the time; temporary separation (TS) calves were separated for 72â¯h from their dams from Day 33 to 36 but remained with their dams the rest of the time. Blood samples and behavioral data were collected on Days 32-36 (1st period) and 149-153 (2nd period). In the 1st period, a greater percentage of RS and TS calves were observed close to the fence line (<10â¯m) that separated them from their dams (P < 0.0001) and vocalized more than CS calves (Pâ¯<â¯0.0001), while in the 2nd period, RS calves had the highest cortisol concentration and vocalization rate (Pâ¯<â¯0.05). Similarly, during the 1st period, a greater percentage of RS and TS cows were observed close to the fence line than CS cows (Pâ¯<â¯0.0001), with TS cows vocalizing the most (P =â¯0.001). In the 2nd period, RS cows had greater cortisol concentration than TS (Pâ¯=â¯0.037) and CS cows (P = 0.003). More TS and CS cows than RS were observed close to the fence line (Pâ¯=â¯0.03 and Pâ¯=â¯0.05). On Day 150, TS calves and cows vocalized more than RS and CS animals (Pâ¯<â¯0.0001). Before calf-cow separation, 27 out of 45 cows were cycling (CSâ¯=â¯10; RSâ¯=â¯6; TSâ¯=â¯11). After separation, 12 of the remaining 18 cows resumed ovarian activity (CSâ¯=â¯3; RSâ¯=â¯5; TSâ¯=â¯4), and all cows were cycling after estrous synchronization treatment. The pregnancy rate was similar between CS, RS, and TS (60, 53, and 60% respectively). In conclusion, temporary separation increased calf distress response to definitive weaning even four months later, while restricted suckling seemed to reduce it.
Assuntos
Estro , Período Pós-Parto , Animais , Animais Lactentes , Bovinos , Feminino , Gravidez , Progesterona , DesmameRESUMO
Communal rearing has been reported in several mammals, including wild ungulates. However, until now, there was no evidence of any alloparental care in the Bos genus. To test the hypothesis that calves' groups are formed under the care of specific cows, a herd of 31 peri-partum zebu cows raised under pasture conditions were used. Groups of ≥ 3 individuals within a 10-m diameter were estimated using aerial pictures taken every other day at 7:00, 10:30, 13:30, 16:00, and 18:00 h, during 6 weeks. Temperament (exit speed, flight distance, intensity of reaction), age, and parity of each cow were registered. A total of 142 groups were observed, and in all of them, at least one calf was present. A total of 75% of the groups were more calves than cows, and in 65.4% of the cases, there were 1 to 3 cows with 2 to 32 calves. While there were no groups integrated only by cows, there were 3.5% integrated only with calves. The most frequent group was formed by 2 calves and 1 cow (14.8%). Parity was positively related with the number of times that a cow was observed in a group (R2 = 0.19, P = 0.01) and with the number of groups in which her calf was present (R2 = 0.16; P = 0.03). The results of the temperament tests were unrelated to the total number of groups in which a cow was observed nor the number of groups with or without its calf. It was concluded that zebu calves congregate in newborn groups in companion with one or more adults, preferably high parity cows, regardless of their temperament.
Assuntos
Temperamento , Animais , Bovinos , Feminino , Paridade , GravidezRESUMO
With the objective of testing the hypothesis if animals with a stable layer of body fat (FAT) during the peripartum have a better chance of becoming pregnant after calving, fifty-nine multiparous Brahman cows in their last trimester of pregnancy were used. Animals averaged four parturitions and were stocked at a rate of 1.25 animal units per hectare and divided into two groups depending on the time postpartum (dpp) that the intravaginal releasing device CIDR was inserted; Group 1 (<30 dpp; n = 30) received the implant at 25.2 ± 4.21 and withdrawn 9 days later. Group 2 (≥30 dpp; n = 29) received the CIDR at 38.41 ± 5.8. Animals were AI at detected oestrus until 170 dpp and calculated as pregnant at first service or requiring more than one service (1s and >1s), not pregnant but cycling (not pregnant) and those not cycling at all (anestrus). The FAT measurements were taken twice each month from the last trimester of gestation until 96 dpp. The onset of ovarian activity was monitored through blood levels of progesterone (P4) at days 14 and 9 prior to CIDR insertion and days 10, 13, 30 and 33 after CIDR withdrawal. Animals pregnant did not have any major changes in their fat thickness. In contrast, cows pregnant in the group ≥30 dpp had changes in their FAT homoeostasis, and pregnant animals in the 1s and >1s groups did not show differences in dorsal back fat in the last trimester of pregnancy and early postpartum. In contrast, animals not pregnant and in anestrus FAT values decreased considerably after parturition. Overall, fertility was 49%, but 18% of all the animals remained anestrus losing FAT. Thus, animals with adequate metabolic conditions will have a better chance of pregnancy regardless of the time postpartum when the reproductive programme starts.
Assuntos
Tecido Adiposo/fisiologia , Anestro/fisiologia , Ciclo Estral/efeitos dos fármacos , Fertilidade/fisiologia , Administração Intravaginal , Animais , Bovinos , Ciclo Estral/fisiologia , Feminino , Inseminação Artificial/veterinária , México , Gravidez/fisiologia , Progesterona/administração & dosagem , Progesterona/uso terapêuticoRESUMO
Low pasture allowance during gestation affects ewes' BW at parturition, the bond with their lamb, lamb development, and thus also may affect their responses to weaning. The objectives were to determine if native pasture allowance from before conception until late pregnancy affects ewe-lamb behaviours at lambing, ewes' milk yield, lambs' BW, and the behavioural and physiological changes of ewes and lambs at weaning. From 23 days before conception until 122 days of pregnancy, 24 ewes grazed on two different native pasture allowances: high (10 to 12 kg of dry matter (DM)/100 kg of BW per day; HPA treatment; n=12) or low (5 to 8 kg of DM/100 kg of BW per day; LPA treatment; n=12). Thereafter, all ewes grazed on Festuca arundinacea and received rice bran and crude glycerine. Ewes' body condition score (BCS) and BW were recorded during pregnancy and postpartum periods. Milk yield was determined on days 32, 41 and 54 after lambing. Lambs' BW was recorded from birth until 72 days after lambing. Latency from parturition until the ewe licked her lamb, maternal behaviour score (a test that evaluates maternal attachment to the lamb) and latency for lamb to stand up and suckle were determined. The behaviour of the lambs and ewes was recorded before and after weaning (at 65 days). The ewes' serum total protein, albumin and globulin concentrations were measured before and after weaning. The HPA ewes presented greater BW (P<0.005) and BCS (P<0.005) than the LPA ewes during pregnancy and postpartum (P<0.04), and had a greater milk yield than the LPA ewes (P<0.03). Treatments did not influence any behaviour at lambing, lambs' BW, neither the ewes' behavioural and physiological changes at weaning. HPA lambs paced and vocalized more than LPA lambs (P<0.0001). The variation of albumin concentration before and after weaning was greater in the HPA lambs than in the LPA lambs (P<0.0001). In conclusion, although ewes' BW, BCS and milk production were affected by pasture allowance until late pregnancy, this did not affect the behaviours that lead to the establishment of the mother-young bond, nor the ewes' behavioural responses at weaning. Lambs reared by ewes that grazed on low pasture allowance during pregnancy presented fewer behavioural changes and a lower decrease of albumin concentration after weaning. Lambs' BW was not affected by the feeding received by their mothers.
Assuntos
Dieta/veterinária , Leite/química , Ovinos/fisiologia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais Recém-Nascidos , Comportamento Animal , Composição Corporal , Peso Corporal , Feminino , Festuca , Lactação , Fenômenos Fisiológicos da Nutrição Materna , Período Pós-Parto , Gravidez , Complicações na Gravidez , DesmameRESUMO
The aim was to determine the progesterone profile after the introduction of bucks during the advanced luteal phase of does. Fourteen does received vaginal sponges impregnated with 40 mg fluorogestone acetate for 12 days, and a luteolytic dose of a prostaglandin analogue (75 μg of D-cloprostenol) 2 days before sponge removal. Fifteen days after sponge withdrawal one buck was introduced in one of the pens (BE group; n = 6), while the female goats in the other pen remained as controls (CON group; n = 8). The buck was replaced every 24 h, alternating their presence until the end of the experiment. Serum progesterone levels were used to monitor ovarian activity. Progesterone concentration from day 14 to 20 varied with time (P < 0.0001), and there was an interaction between treatment and day (P = 0.02). While progesterone concentration increased from day 15 to day 16 in BE does (P = 0.01), there were no changes in CON does on those days (P = 0.2). On the other hand, progesterone concentrations decreased in BE does from day 18 to day 19 (P = 0.02), without changes in CON does (P = 0.6). Finally, there was a sharp decrease from day 19 to day 20 in both BE (P = 0.0009) and CON (P < 0.0001) does. Overall, our results demonstrated that the introduction of bucks during the late luteal phase of isolated does can induce changes in the progesterone pattern, showing an early increase followed by a pronounced withdrawn.
Assuntos
Feminino , Animais , Cabras/anatomia & histologia , Cabras/fisiologia , Fase Luteal/metabolismo , Progesterona/análise , Ciclo Estral , LuteóliseRESUMO
The aim was to determine the progesterone profile after the introduction of bucks during the advanced luteal phase of does. Fourteen does received vaginal sponges impregnated with 40 mg fluorogestone acetate for 12 days, and a luteolytic dose of a prostaglandin analogue (75 μg of D-cloprostenol) 2 days before sponge removal. Fifteen days after sponge withdrawal one buck was introduced in one of the pens (BE group; n = 6), while the female goats in the other pen remained as controls (CON group; n = 8). The buck was replaced every 24 h, alternating their presence until the end of the experiment. Serum progesterone levels were used to monitor ovarian activity. Progesterone concentration from day 14 to 20 varied with time (P < 0.0001), and there was an interaction between treatment and day (P = 0.02). While progesterone concentration increased from day 15 to day 16 in BE does (P = 0.01), there were no changes in CON does on those days (P = 0.2). On the other hand, progesterone concentrations decreased in BE does from day 18 to day 19 (P = 0.02), without changes in CON does (P = 0.6). Finally, there was a sharp decrease from day 19 to day 20 in both BE (P = 0.0009) and CON (P < 0.0001) does. Overall, our results demonstrated that the introduction of bucks during the late luteal phase of isolated does can induce changes in the progesterone pattern, showing an early increase followed by a pronounced withdrawn.(AU)
Assuntos
Animais , Feminino , Cabras/anatomia & histologia , Cabras/fisiologia , Fase Luteal/metabolismo , Progesterona/análise , Luteólise , Ciclo EstralRESUMO
The purpose of this study was to examine the effect of day length on seminal characteristics, testicular size, sexual behaviour and testosterone (T4) concentration in pelibuey rams subjected to different semen collection frequencies. eighteen intact males were assigned randomly to one of two semen collection frequencies: in the high rate (HR) treatment, two ejaculations per week were obtained from each ram; one ejaculation every two weeks was collected under the low rate (LR) treatment. All animals were housed individually in contiguous 5 m x 5 m wire mesh pens and evaluated over a 12-month period. At the beginning of the experiment rams were 20 months old and 40-50 kg in weight. All rams ejaculated and produced semen throughout the year. Semen volume, sperm per ejaculation, testicular circumference and testicular volume were significantly (p < 0.05) greater during short days in all rams, regardless of the semen collection frequency, with the exception of sperm concentration, for which no variation was found in hr individuals, and reaction time and T4 levels, for which no variation was found in IR males. Rams subjected to HR collection were more affected by the short-day photoperiod than rams collected twice per week, exhibiting greater reduction (p < 0.05) in time to achieve their first ejaculation and in sperm per ejaculation, as well as greater increases (p < 0.05) in T4 concentration than IR rams (14.65 +/- 1.22 vs 23.53 +/- 5.34 s, (3.37 +/- 0.17) x 10(9) vs (3.52 +/- 0.20) x10(9) sperm and 8.68 +/- 0.44 vs 6.85 +/- 0.74 ng/ml, respectively). It was concluded that: (a) the magnitude of the seasonal effects was not sufficient to prevent the rams being used for breeding throughout the year, and (b) seasonal variation within variables was affected differently between semen collection frequencies.
Assuntos
Ejaculação/fisiologia , Comportamento Sexual Animal/fisiologia , Carneiro Doméstico/fisiologia , Testículo/anatomia & histologia , Testosterona/sangue , Animais , Masculino , Tamanho do Órgão , Fotoperíodo , Distribuição Aleatória , Estações do Ano , Sêmen , Carneiro Doméstico/sangue , Contagem de Espermatozoides/veterináriaRESUMO
Although the order of entry to a handling chute is related to social rank, it is still not clear what the consequences are for Zebu cattle of occupying different ranks when being exposed repeatedly to a stressful handling procedure. Eighteen Brahman cows were observed for 243 h to obtain information on social interactions. From that information, indices of success in displacing other individuals of the herd were calculated to reflect social status of each cow. One week after behavioral observations, the cows were forced 19 times to enter a handling chute where they were palpated and 7 ml of blood was collected from their caudal vein. To have an adrenal activity profile along the experimental period, five blood samples (Days 2, 6, 10, 15, and 19) were chosen for cortisol determination. On each sampling day, the average time in the chute, the order of entry, and a value of entrance consistency were calculated. On average, the high-ranking cows entered the chute before the medium- and low-ranking cows. Medium-ranking cows showed higher consistency when entering the race than high- and low-ranking cows. Low-ranking cows had significantly lower cortisol levels than the other two groups since the second sample (Day 6 in the race), and had higher cortisol levels the first time handled than at subsequent sampling days. It is suggested that low-ranking cows adopt a passive strategy that allows them to have a better control over the stressful event, while high-ranking cows respond with higher cortisol levels perhaps because of the need to become aroused to deal with challenges. It was concluded that the herd (a) habituated to repeat handling in a squeeze chute and (b) low-ranking cows responded with lower cortisol concentration to handling.
Assuntos
Hierarquia Social , Estresse Psicológico/fisiopatologia , Glândulas Suprarrenais/fisiopatologia , Algoritmos , Animais , Bovinos , Feminino , Manobra Psicológica , Hidrocortisona/sangue , Atividade Motora/fisiologia , Restrição FísicaRESUMO
We present a case report of a renal angiomyolipoma with the special feature of its big size at the moment of the diagnosis. It is appreciated an important alteration of the kidney morphology and the repercussion produced in the rest of the abdominal organs. Due to this an exeresis with nefrectomy is performed. We do a bibliographic review and we analyzed the relevant aspects of this tumour.
Assuntos
Angiomiolipoma/patologia , Neoplasias Renais/patologia , Adulto , Angiomiolipoma/cirurgia , Feminino , Humanos , Neoplasias Renais/cirurgia , NefrectomiaRESUMO
The effect of management of the female stimulus during semen collection and its association with libido re-establishment and the semen characteristics of sexually mature goats was evaluated. Eight 2-yr-old bucks were individually subjected to 12 weekly trials in which one of the following three treatments was applied alternately. In treatment one, each male performed two ejaculations on an estrus-induced, restrained doe and semen was collected with an artificial vagina (AV). In treatment two, males were collected as in the former treatment, but a different doe served as the stimulus female for the second ejaculation. In treatment three, two restrained does were present while collecting each buck, allowing males to choose which female to mount and serve in each of the two collections. Number of mounts before first ejaculation and reaction times (period from introduction of the ram to the test arena to his first ejaculation) were similar among treatments (P > 0.05). A significant (P < 0.05) decrease was found for number of mounts performed before achieving the second ejaculation and for latency between ejaculations in the third treatment. No differences (P > 0.05) were found for semen volume (0.8+/-0.03, 1.0+/-0.03, and 0.9+/-0.02 mL) or sperm concentration (4.4+/-0.15, 4.6+/-0.13, and 4.4+/-0.86 spermatozoa/mL) among the three treatments or between the first and second collection. However, a trend to decrease volume and concentration was observed. It was concluded that the simultaneous presence of two females while bucks are collected reduced the number of mounts performed before the second ejaculation and the latency between ejaculations.