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In order to compare in vivo performance and environmental adaptation of two genetic types of goats raised in north-eastern Brazil, 20 females (10 local and 10 Saanen x local) were used in this experiment. During the late rainy season the goats were monitored for the following parameters: body weight, body (BT) and skin temperature (ST), respiratory (RR) and heart rate (HR) as well as the air temperature (AT) and humidity (HU) in the pens in the morning (MR) and afternoon (AR). From May to June the crossbred goats showed a significant gain (P< 0.05); the live weight of F1 was superior to the local goats (P< 0.05) at the end of the experiment. The physiological response during the AR was significantly superior to MR (P< 0.05) for all parameters. The local goats achieved the highest values of BT and ST during the experiment. On average, the physiological rhythms (RR and HR) were higher in crossbred than local goats. In conclusion, crossbred goats showed to be less at risk to environmental stress condition in north-eastern Brazil.

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&lt;0.05). The oocyte retraction rate in the Q8 group was higher (P&lt;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&lt;0.05). The percentage of MII oocytes was higher in the Q4 group than in the CIS group (P&lt;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&lt;0.05). In addition, oocytes matured with 4 μM quercetin showed higher mitochondrial activity than matured oocytes in the CIS and Q8 groups (P&lt;0.05). In conclusion, 4 μM of quercetin can be used as an alternative to cysteamine in the in vitro maturation of goat oocytes.

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.

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.