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Cobia (Rachycentron canadum) is a coastal pelagic migratory fish species of tropical and subtropical waters, where it is an important game fish and it has been commercially expanded in offshore aquaculture systems. Understanding population connectivity is of utmost importance to the sustainable use and conservation of aquatic resources, and information on genetic diversity and structure is key element in unraveling differentiation when no clear physical barriers exist. In the present study, cobia genetic diversity and structure were depicted using mitochondrial DNA cytochrome b sequencing and microsatellite genotyping in samples from the Southwestern Atlantic and showed that a major single population inhabits the southern hemisphere. Cytochrome b sequencing also suggested that the Indian Ocean is the center of origin for this species' diversification. A hierarchical analysis of AMOVA compared sampling locations from the Northwestern Atlantic (from a previous study) with the Southwestern ones using nine shared microsatellite markers. Differentiation among groups (FCT = 0.41), Bayesian clustering analysis, and complementary ordination analyses (by discriminant analysis of principal components [DAPC] and factorial correspondence analysis [3D‐FCA]) presented a clear separation between the two hemispheres, supported by a Lagrangian model that explained the ocean dynamics over larval retention on the Western Atlantic. Another genetic subgroup intermingled with the main Southwestern group may also exist further south, probably associated with the Vitória‐Trindade Ridge and the local current systems. The distribution of this species in metapopulations is of extreme relevance for fisheries and fish hatcheries management in the Atlantic Ocean. [ABSTRACT FROM AUTHOR]

Increasing voluntary feed intake of the sow is a major challenge for nutritionists in tropical climate conditions. The present study aimed to evaluate the impact of the dietary supplementation of a feed flavour for sows during lactation on their feeding behavior and kinetics of daily feed intake under tropical conditions. A total of 60 high-prolific mixed parity sows divided into 10 batches of 6 sows each were used, distributed in a completely randomized experimental design among 2 dietary treatments (0 or 500 g/ton of Krave®, Adisseo). The average meal size was 107 g/meal lower in sows fed the control diet when compared with flavour fed sows. Daily feed intake was greater in the flavored diet than in the control (6,417 vs. 5,362 g/d; P < 0.05). The flavor improved ingestion time (58.4 vs. 46.6 min/d, respectively flavour and control; P < 0.05). Sows receiving flavor showed a higher nocturnal (704 vs. 583 g/meal) and diurnal (678 vs. 582 g/meal) feed intake. Sows also showed a higher voluntary intake between 00:00 and 10:00 am, which was equivalent to 83% of the total daily feed intake. From a comparison of hourly feed intakes or variations from hour to hour (during 24 h), the nycthemeral pattern of feed intake peaked twice daily for both dietary treatments. However, the size of the peak was greater (P < 0.05) for flavour fed sows when compared with the control at 0400 and 1900 h (Figure 1a). Diets also influenced on kinetics of daily feed intake during the lactation period. Feed intake was higher for the flavour fed sows from d 3 to 8 and from d 10 to 24 (Figure 1b; P < 0.05). In conclusion, the strategic use of a feed flavour to manipulate the sensorial properties of feed is a viable strategy to increase the sows' voluntary feed intake. [ABSTRACT FROM AUTHOR]

Water is an absolute requirement in the daily needs of the pig. It has been suggested that after weaning, pigs may not consume enough water which impacts in their hydration. It is commonly known that providing water to piglets encourages higher feed intake and improves nutrient absorption, with a positive impact on weight gain and on post-weaning feed intake adaptation, decreasing problems caused by the transition phase from the farrowing unit to the nursery. The objective of this study was to evaluate the effect of the addition of a flavor to the drinking water of piglets on their voluntary water intake and performance in the first week after weaning. Sixty (30 males and 30 females) commercial piglets were used, in a randomized block design, with 10 repetitions per treatment (with or without addition of 100g/1000 L of water of Power sweet®; Adisseo) and each repetition with 3 animals. The piglets were weighed at weaning and d 8 post weaning. Parameters evaluated were the initial and final weight; daily weight gain; average daily and total feed intake; total daily and average consumption per animal of water and correlation between feed and water consumption. The means of the variables were submitted to the Pdiff option of the SAS using the Tukey test for contrasts (P < 0.05). The addition of a flavor in the drinking water increased daily weight gain in 6.7% (P = 0.041), average daily feed consumption in 2.98% (P = 0.0014), total feed consumption in 2.96% (P = 0.0014) and increased the final weight by 1.25% (P = 0.0411) when compared the control. Feed and water intake had a positive correlation in both treatments. The addition of flavor to the drinking water increases feed and water intake, improving the piglet performance in the first week after weaning. [ABSTRACT FROM AUTHOR]

Probiotics are being considered as an alternative means to reduce pathogen infection and improve animal health especially around the time of weaning. The objective of our study was to evaluate the effects of the use of a probiotic in diets for piglets on their performance and intestinal integrity during nursery phase. Thirty-six piglets (18 barrows and 18 females), weaned at 24 days of age were distributed in a randomized block design, with six repetitions per treatment (with or without addition of 50g/ton of the probiotic Bacillus subtilis DSM 32315, GutCare®, Evonik Industries) and each repetition with three pigs per experimental unit. During the experimental period, performance parameters evaluated were body weight (BW), daily feed intake (ADFI), feed conversion, average daily weight gain (ADG) and the intestinal integrity assessed via galactose absorption capacity. The performance data were submitted to the PDIFF option of the SAS and compared using the Tukey test. During phase 1 (24 to 31 days of age) the use of the probiotic tended (P = 0.07) to improve ADG (+76 g/d) in comparison to control. As for phase 2 (32 to 39 days of age), 3 (40 to 53 days of age) and 4 (54 to 70 days of age) the use of the probiotic increased the ADFI (+118, +66 and +162 g/d, respectively; P < 0.05) and ADG (+5 and +8%, respectively for phase 2 and 3; P < 0.05) compared to control. The use of the probiotic improved (P = 0.05) nursery end BW (+1.3 kg) and overall ADFI (+8%; P = 0.046). The intestinal integrity was not affected by treatments (P > 0.10) at any stage. In conclusion, the use of the probiotic Bacillus subtilis DSM 32315 in diets for weaned piglets can be used as a viable formulation strategy to improve performance and the intestinal health of the animals during nursery phase. [ABSTRACT FROM AUTHOR]

Heat stress can cause changes in the feeding behaviour of lactating sows. The present study aimed to evaluate the impacts of season on the feeding behavior and kinetics of daily feed intake of modern high prolific sows under tropical conditions. A total of 80 high-prolific mixed parity sows divided into 10 batches of 8 sows each were used. Individual feeding behaviour was recorded during the ad libitum period (between d 1 and 23 of lactation), using an Automated Intelligent Feeder (AIF; Gestal Solo, Jyga Technology, Canada). Daily feed intake during lactation was affected by season (P < 0.001), and the feed intake was less during the hot season (5.66 vs. 7.23 g/d; Figure 1a). The daily ingestion time was less in the hot season (36.8 vs. 72.3 min/d; P< 0.01) and the ingestion time per meal was also lower in the hot compared to the cool season (5.7 vs. 7.5 min/meal; P < 0.05). The hot season showed a lower (P < 0.01) rate of daily intake when compared to the cool season (36.8 vs. 72.3 g/min). Sows showed a higher diurnal feed intake (3,546 vs. 2,901 g/d), whereas meal frequency was not affected (4.2 meals/d, on average). Irrespective of the season, the nycthemeral pattern of feed intake peaked twice daily: between 0200 and 0900 h and between 1600 and 2000 h (Figure 1b). The present study confirms that lactating sows do not change much their feeding pattern according to season, meaning that they tend to keep the same feeding behaviour during both seasons, with a more pronounced intake between 0200 and 0900 am, approximately 80% of their total daily intake. Sows may not change feeding pattern according to season, but reduce significantly voluntary feed intake under hot climate conditions in order to reduce the thermal effect of feed. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate the impact of a mycotoxin deactivator in diets containing added mycotoxins for gestating and lactating gilts on their performance. A total of 60 gilts (LD x LW) were used. After insemination the gilts were distributed among 3 dietary treatments according to a randomized block design: a negative control (CON); mycotoxin positive control (Myc); and a positive control added a mycotoxin deactivator (Myc+Deact 2 kg/ton; Unike®Plus, Adisseo). The total mycotoxins levels added to the diets 2 and 3 from d 75 of gestation until farrowing were: DON at 2.5 mg/kg, FBs at 10 mg/kg, and ZEA at 0.75mg/kg. Sows received the experimental diets from d 75 of gestation until weaning (i.e. 21 d). At farrowing, total number of piglets born, born alive, stillborn, and mummies were measured. Piglets were individually weighed 24-h post-farrowing, and at weaning to determine litter performance during lactation. The effects of diet composition, blocks and initial weight were tested according to a general linear procedure analysis of variance (GLM procedure of SAS). During gestation, treatments influenced (P = 0.022) sow mortality rate: CON had no mortality and Myc 15.8% and Myc+deact 10.5%. Same observation was made for the lactation period (P = 0.017): CON showed a lower mortality rate compared to the mycotoxin fed sows (5.0 vs. 31.2 vs. 11.8%, respectively for CON, Myc and Myc+deact). Sow milk production yield was greater (P = 0.021) in CON (11.66 vs. 9.53 vs. 9.67 kg/d, respectively for CON, Myc and Myc+deact). As a consequence of that, treatments also influenced piglet (P = 0.047) and litter (P = 0.048) weight with a higher value for CON sows, followed by Myc+deact and Myc. Our findings showed that the use of the deactivator can mitigate the negative effects on performance when animals are subjected to diets contaminated by challenging levels of mycotoxins. [ABSTRACT FROM AUTHOR]