Influence of feeding sorghum on the growth, gizzard development and carcass traits of growing geese

Effect of dietary modulation of fiber and fat level on liver and kidney functions, lipid profile, antioxidant and immune parameters in growing Egyptian geese

Determining the optimal requirements from dietary fiber and fat for Egyptian geese is a matter of great concern regarding health, production and growth. Therefore, the current study estimated the effects of different dietary fiber and fat levels on functions of liver and kidney, lipid profile, immunity and antioxidant measurements of the growing Egyptian geese. 150 Egyptian goslings (4 weeks old), with almost the same body weights were randomly allocated into 6 groups (25 goslings/group). All groups were subdivided into five replicates, each replicate contains five geese. Liver and kidney functions, immunity and antioxidant parameters were not significantly affected the different studied levels of fiber and fat or by their interaction. Various levels of fiber significantly affected total cholesterol, triglycerides, LDL-cholesterol and VLDL-cholesterol in a concentration-dependent manner and the lowest the lipid profile values were obtained at 12%. In conclusion, the present findings show that use of dietary fiber up to 12% and 5% dietary fat showed no detrimental effects on the immune status and general health of geese and resulted in the preferable lipid profile. This experiment provides a base for further study about the optimal requirements from dietary fiber and fat for the growing Egyptian geese.

Consequences of varying dietary crude protein and metabolizable energy levels on growth performance, carcass characteristics and biochemical parameters of growing geese

This research aimed to investigate the effect of varying dietary crude protein (CP) and metabolizable energy (ME) quantity on growth, carcass characteristics, biochemical blood parameters and molecular aspects of growing geese. Overall, a total of 180 Egyptian goslings were used in a 2 × 3 factorial design. Two levels of CP (18% and 16%) and three levels of ME (3000, 2900 and 2800 kcal/kg diet) were employed. Growth traits showed no significant differences as a result of different CP or ME levels. Birds fed the higher CP level consumed more feed than the lower. Carcass, dressing, heart, spleen, abdominal fat and thigh percentages within the group fed 18% CP were higher than the other group. Compared with the other ME-based diet, geese fed a low-ME based diet had the highest heart percentage. Feeding growing geese on a 2900 Kcal/kg ME-based diet increased the serum content of total protein and globulin. Geese fed the high-ME diet showed the highest levels of ALP and C4 as compared with other ME levels. Regarding Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), different protein and energy levels did not affect the molecular weight of blood proteins of Egyptian geese during the growing phase. It could be concluded the levels of 16% CP and 2800 kcal/kg ME are enough to maintain the growth performance and the other physiological indices as well as molecular aspects.

Comparison of the composition and sensory characteristics of goose fatty liver obtained by overfeeding and spontaneous fattening1

Spontaneous liver steatosis can be experimentally induced in domestic Greylag geese by combining a short photoperiod with a sequence of feed restriction followed by ad libitum corn feeding. This could offer an alternative to the conventional "foie gras" production system based on overfeeding. The present work aimed at comparing the compositional characteristics, sensory profile, and acceptability by a consumer panel of fatty livers obtained by overfeeding and spontaneous fattening. In all, 210 male geese were used: 125 geese were raised over a 31-wk period to produce fatty liver without overfeeding ("alternative livers") and 85 were raised using conventional methods with overfeeding ("conventional livers"). Mean liver weight was over 1 kg (1,102 g) in the conventional group and 445 g in the alternative group. The characteristics of the livers were studied in 2 subpopulations: 44 conventional livers representative of the experimental population (mean liver weight 1,064 g) and 42 alternative livers weighing more than 400 g (mean 702 g). Compared with the alternative livers, livers from the conventional group showed significantly (P < 0.05) higher dry matter and lipid contents, lighter color (L*), and lower yellowness (b*). The neutral lipids of alternative livers contained significantly less triglycerides and free fatty acids and significantly more cholesterol and cholesterol esters than those from conventional livers. Detailed analysis of the fatty acid composition of triglycerides showed that the proportion of mono- and polyunsaturated fatty acids was significantly higher in the alternative livers. However, covariance analysis suggested that these differences in lipid composition were mainly due to differences in lipid content between both types of livers. The evaluation of cooked livers by a trained expert panel revealed significant differences in the sensory profile between the conventional and alternative livers. The acceptability by a consumer panel was significantly lower in alternative compared to conventional livers. This difference was not related to weight and/or lipid content since livers of similar weight range (800 to 1,000 g) were compared and showed clear-cut differences for hedonic scores.

The influence of whole-corn feeding method during the finishing stage on the performance of overfed mule ducks

The aim of this trial was to compare 2 feeding systems based on whole corn, a loose-mix and a free-choice feeding system, during the finishing stage on the performance of ducks. Five hundred sixteen day-old male mule ducks (Muscovy drake × Pekin duck) were divided into 3 groups that differed in the presentation of the diet they received between 58 and 88 d of age: a complete pelleted diet (Control (CON) group; AMEn 12.1 MJ/kg, CP 15.0%) containing 500 g of corn per kg; or whole corn (AMEn 13.9 MJ/kg, CP 7.3%) and protein-rich pellets (AMEn 10.3 MJ/kg, CP 22.7%) in equal quantities mixed in the same feeders (loose-mix feeding [LMF] group) or in 2 separate feeders (free-choice feeding [FCF] group). From 89 to 99 d, 72 birds/group were overfed with a mixture containing mainly corn and water and then slaughtered to determine the weight and commercial value of the fatty liver. Feed intake was measured daily. Body weight (BW) was measured at 58, 88, and 99 d of age. From 58 to 88 d, total feed intake of the FCF group was +7% and +9% (+558 g and +672 g) higher than in the groups CON and LMF, respectively (P = 0.005). At 88 d, the BW was higher in the CON group than in the FCF group (4,959 vs. 4,778 g, P < 0.001), the LMF group being intermediate (4,874 g). During the experimental stage, the feed conversion ratio was higher in the FCF group than in the 2 others (+32%, P = 0.024), but the energy intake was similar between the 3 groups (92.6 MJ/duck, P = 0.353).After overfeeding (99 d), the BW (6,593 g), weight (642 g), and commercial grading of fatty liver were similar (P > 0.05) in the 3 groups. The present results suggest that loose-mix feeding during the finishing stage using whole corn is a solution for reducing feed cost.

The influence of choice feeding and cereal type (corn or triticale) during the finishing period on performance of mule ducks

The aim of this trial was to study the influence of choice feeding and cereal type (corn or triticale) during the finishing period on performance of ducks. In total, 624 one-day-old male mule ducks (Cairina moschata × Anas platyrhynchos) were divided into 3 groups differing in the diet they received between 56 and 84 d of age: a commercial complete pelleted diet (control group; AMEn 12.1 MJ/kg, CP 15%), or corn whole seeds (AMEn 14.4 MJ/kg, CP 7.3%) and protein-rich pellets (AMEn 9.9 MJ/kg, CP 22.7%) in 2 separated feeders [choice feeding with corn (CFC) group]; or triticale whole seeds (AMEn 13.0 MJ/kg, CP 10.5%) and protein-rich pellets (AMEn 11.2 MJ/kg, CP 19.5%) in 2 separated feeders [choice feeding with triticale (CFT) group]. From 85 to 96 d, 96 birds/group were overfed with corn. Feed intake (complete pellets or cereal and protein-rich pellets) per pen was measured at 60, 62, 65, 69, 78, and 84 d of age. Body weight and body traits were measured at 56 to 84 d of age. Over the entire period, from 56 to 84 d, the feed intake of the CFC group was 7% lower than the control group, and 5% lower than that in the CFT group (P = 0.002). Whatever the diet tested, at 56 and 84 d of age, the BW (4,099 and 4,779 g, P = 0.42 and P = 0.35, respectively) and the carcass traits (P > 0.05) of ducks were similar in the 3 groups. During and after overfeeding, the performances of the ducks were also similar (P > 0.05). The present results suggest that CFC during the finishing period is a solution to reduce the cost of diet destined to ducks. Indeed, using locally grown grains could reduce the economic and environmental impacts of duck feeding, reducing the transportation and crushing processes.

Effects of substituting yellow corn for sorghum in geese diets on magret and foie gras quality

The aim of this trial was to study the effects of substitution of yellow corn with sorghum during the growing-finishing (G period), overfeeding (O period), or both periods on magret and foie gras quality in geese. In total, 260 ganders were divided into 4 groups (65 birds in each) differing in the cereal (yellow corn or sorghum) included in the diet given during the G and the O periods, using a 2 × 2 factorial arrangement of treatments. The groups differed in the nature of the cereal in the diet offered to birds between 44 and 104 d of age (G period: a diet containing 500 g of sorghum/kg (SS and SC groups) or a diet containing 500 g of yellow corn/kg (CS and CC groups). The groups differed also in the diet offered to birds between 105 and 120 d of age (O period): 967 g of yellow corn/kg (SC and CC groups) or 965 g of sorghum/kg (SS and CS groups). At the end of the O period, the birds were slaughtered after 10 h of fasting to measure foie gras and breast muscle weight, color, and chemical composition. The mortality in the SC group was higher (P < 0.05) than in the other 3 groups (14.29 vs. 3.58%, average of the 3 groups). After overfeeding, birds fed with sorghum had foie gras that were heavier 984 vs. 885 g, in CS+SS vs. CC+SC groups, respectively; P < 0.001) and less yellow (18.03 vs. 23.97 for b*, in CS+SS vs. CC+SC groups, respectively, P < 0.001) than birds fed with corn. The substitution of yellow corn with sorghum during the G and O periods (SS group) increased the weight of the foie gras, but altered its color to a paler yellow. In contrast, a substitution during the G period only (SC group) resulted in increased mortality during the O period.