Impact of Diet Supplementation and Age at Slaughter on Carcass Characteristics of Creole Goats.

The objective of this study was to evaluate the effects of diet and age on finishing performances and carcass characteristics of male Creole goats. A total of 91 weaned male Creole kids [84 days old ± 7 days, 9.2 kg live weight (LW) ± 0.5 kg] were randomly allocated in a 2 × 3 experimental design. The animals were fed individually with two diets: C0: a 28-day-old Digitaria decubens grass alone, or C50: the same grass plus a commercial concentrate (50% of the total diet) and then slaughtered at 7, 11, or 15 months of age. Significant feeding regimen and age at slaughter effects were observed on the goat carcass characteristics. The addition of concentrate improved the average daily gain (ADG), the dressing percentage, and the conformation score (1-5 scale) from 46 to 88 g/day, 52.8 to 62.4%, and 2.2 to 4.9, respectively. Moreover, carcasses of the C0 group appeared lean with less developed fat than the C50 group and lighter than visceral fat. The meat color was significantly more affected by diet than age. Our data suggested that the production of heavy carcasses with low proportions of fat in the meat is possible in this local breed. The valorization of such a forage feeding system until 11 months of age or with the addition of concentrate from 7 to 11 months of age should be evaluated economically.

Mixed Grazing and Dietary Supplementation Improve the Response to Gastrointestinal Nematode Parasitism and Production Performances of Goats.

Small ruminants are very affected by gastrointestinal nematode (GIN) parasitism worldwide. The improvement of the host protective response and the reduction of the probability of contact between hosts and parasites appear as very promising strategies. The objective of this study was to evaluate the effect of a combination of two components of these two strategies on natural GIN infection and production performances of Creole goat kids: dietary supplementation and a rotational mixed grazing system. One hundred and twenty weaned Creole kids and six Creole heifers were divided into four experimental batches: Splus (supplemented) vs. Szero (non-supplemented) × Mixed grazing (kids associated with heifers) vs. Control (kids alone), and grazing plots of forage grasses were balanced for live weight (LW) in both species. The feed intake, blood, and parasitological parameters and production performances between 3 and 11 months of age were monitored. The fecal egg count (FEC) was significantly lower and the packed cell volume (PCV) significantly higher in the Mixed grazing groups. No effect of supplementation was observed for FEC. In contrast, PCV, body condition score, and live weight were significantly higher in supplemented animals whatever the groups. Mixed grazing system and supplementation had significant effects on the slaughter parameters (P < 0.05), but there was no significant interaction. Our results suggested that the advantage driven either by mixed grazing or dietary supplementation on kids' performances would be equivalent, and the combination of both would improve the animal performances.

Effect of feed restriction and refeeding on performance and metabolism of European and Caribbean growing pigs in a tropical climate.

Reduction in feed intake is a common physiological response of growing pigs facing stressful environmental conditions. The present experiment aims to study (1) the effects of a short-term feed restriction and refeeding on pig performance and metabolism and (2) the differential response between two breeds, Large White (LW), which has been selected for high performance, and Creole (CR), which is adapted to tropical conditions. A trial of 36 castrated male pigs (18 LW and 18 CR) was carried out. For each breed, half of the animals were restrictively fed at 50% of the standard feed allowance for 6 days and then fed normally for the next 14 days. Growth performance, thermoregulatory responses, plasma hormones and metabolites were measured. Results showed that, for all traits, the difference in response between the two breeds was small and rarely significant, which may be due to the short duration of the feed restriction. Irrespective of breed, feed restriction induced a reduction of growth rate and feed efficiency that was rapidly compensated for upon refeeding. Feed restriction also reduced skin temperature, rectal temperature and respiratory rate, as well as blood urea and cholesterol, which are of interest as potential biomarkers for feed restriction.

Effects of hydration level and heat stress on thermoregulatory responses, hematological and blood rheological properties in growing pigs.

Heat stress is one of the major limiting factors of production efficiency in the swine industry. The aims of the present study were 1) to observe if hemorheological and hematological parameters could be associated to physiological acclimation during the first days of heat stress exposure and 2) to determine if water restriction could modulate the effect of thermal heat stress on physiological, hematological and hemorheological parameters. Twelve Large White male pigs were divided into an ad libitum and a water restricted group. All pigs were submitted to one week at 24 °C (D-7 to D-1). Then, at D0, temperature was progressively increased until 32 °C and maintained during one week (D1 to D7). We performed daily measurements of water and feed intake. Physiological (i.e., skin temperature, rectal temperature, respiratory rate), hematological and hemorheological parameters were measured on D-6, D-5, D0, D1, D2 and D7. Water restriction had no effect on physiological, hematological and hemorheological parameters. The first days of heat stress caused an increase in the three physiological parameters followed by a reduction of these parameters suggesting a successful acclimation of pigs to heat stress. We showed an increase in hematocrit, red blood cell aggregation and red blood cell aggregation strength during heat stress. Further, we observed an important release of reticulocytes, an increase of red blood cell deformability and a reduction of feed intake and blood viscosity under heat stress. This study suggests that physiological acute adaptation to heat stress is accompanied by large hematological and hemorheological changes.

Carcass conformation and cut composition of Creole goat from Guadeloupe.

Carcass data base of 164 Creole male goats was used in order to provide factual data on the carcass conformation. Standardised procedures of carcass measuring and cutting were followed. The European official grid of light lamb is implemented for meat goat in the French West Indies and included five levels. Weights of carcass, cuts and tissues, quality scores and linear measurements were analysed. Feeding system, age at slaughter and weight were taken into account for statistical analysis. There were significant differences among carcass conformation classes (CC) for many traits except for the fat score, leg length and compactness ratio (carcass width on length): 2.2, 34.5 cm and 0.30 on average, respectively. The values of chilled carcass weight and yield and the carcass linear measurements steadily increased until conformation class 4 or 5: 6.7 to 11.2 kg, 49% to 55% and 52.4 to 58.0 cm carcass length. For the weights of carcass cuts, significant differences appeared between two groups: classes 1 and 2 vs. classes 3, 4 and 5. Regardless of the carcass weight, the distribution of prime cuts remained similar. The indices calculated on a weight basis (kg/cm), either for the carcass or the leg, increased significantly (P<0.01): with 54% and 63% difference between the two extreme classes, respectively. The muscle, bone and fat proportions in the shoulder did not vary between CC with 0.72, 0.22 and 0.06, respectively. Corresponding traits in leg were 0.74, 0.23 and 0.03; the last two were different (P<0.05) from class 1 to class 5. The muscle/bone ratios calculated either in shoulder or in leg ranged from 3.1 to 3.6 (P>0.05).