Effects of the partial substitution of fish meal by soy bean meal with or without mannanoligosaccharide and fructooligosaccharide on the growth and feed utilization of sharpsnout seabream, Diplodus puntazzo (Cetti, 1777): preliminary results

The present study was carried out in order to investigate the effects of the mannanoligosaccharide (MOS) and fructooligosaccharide (FOS) on sharpsnout seabream, Diplodus puntazzo in the context of partial fish meal substitution by soybean meal. One-hundred-forty-four sharpsnout seabream of about 100 g initial body weight were randomly divided in 12 experimental tanks (180 litre each). Testing conditions included 12 fish per tank, with triplicate tanks for treatment. The experimental period lasted 114 days. Average water temperature was 21.9±1.6°C, salinity was 30.0‰ and pH ranged from 7 to 8. Four isonitrogenous-isolipidic diets were tested: a control diet (FM) with fish meal as the sole protein source; a second diet (SBM) with approximately 40% of the protein supplied by soybean meal. The remaining two diets were formulated adding 8 g of MOS and FOS per kg of the SBM diet respectively. Average final weight, specific growth rate, feed conversion ratio and protein efficiency ratio remained unaffected by partial fish meal substitution and by MOS or FOS supplementation. Also apparent digestibility coefficients values for organic matter, protein, lipid and energy were not significantly affected by dietary treatment

Use of mannan oligosaccharides during "post-weaning enteric syndrome" in rabbits: effect on in vivo performance from 35 to 60 days

Four groups, each consisting of 684 weaned (35 days) hybrid Hyla rabbits were fed ad libitum the same commercial concentrate supplemented, respectively, with antibiotics (AGP group: colistin sulphate 144 mg/kg; tylosin 100m g/kg and oxytetracyclin 1000 mg/kg) or with mannan oligosac- charides (MOS) at 0.5 (group MOS_0.5), 1.0 (group MOS_1.0) and 1.5 g/kg (group MOS_1.5). Up to 60 days, mortality rate was recorded daily. For each group, 64 rabbits were controlled weekly for live weight to calculate daily weight gain (DWG). Feed intake (and, by consequence, feed conversion ratio) was measured, weekly, per group. No differences were observed for live weight during the trial, while DWG showed an alternate trend, in general, significantly lower for AGP group, exclusive of the third week (49- 56 days). Exclusive of the first week of the trial feed intake was higher for AGP than the other groups and the feed conversion ratio was more favourable for MOS groups. Mortality rate was significantly higher (34.2%) in AGP groups. The lowest mortality was recorded in MOS_1.0 group (7.75%)

Somatic indexes, chemical-nutritive characteristics and metal content in caught and reared sharpsnout seabream (Diplodus puntazzo)

The aim of this study was to compare some somatic indexes, chemical-nutritive characteristics and the contents of some metals (Pb, Cu, Cr and Zn) in the whole body and fillet from caught and reared sharpsnout seabream (Diplodus puntazzo). The fish came from three different conditions: reared in marine cages (R), captured in a natural lagoon (L) and in the Mediterranean sea (S). Thirty fish per group, divided into three weight categories (100±15.3, 200±18.7 and 300±20.4g), were used for the trial. Reared sharpsnout seabream showed higher amounts of celomatic fat (3.41%, 2.43%, 0.21%, respectively for R, L and S) and total lipid (13.86%, 11.23% and 5.06% respectively for R, L and S), and lower moisture (64.14%, 65.54%, 71.53%) and protein (17.73, 19.03 and 19.17%) than those caught in the lagoon and sea. The whole body of reared fish contained lower amounts of lead (0.70, 0.75 and 0.97mg/kg, respectively for R, L and S), copper (0.15, 0.38, 0.25mg/kg) chrome (2.19, 3.52, 3.77mg/kg) and higher zinc contents (63.47, 53.42, 47.31mg/kg) than caught fish. Fatty acids from sharpsnout seabream fillets showed a high lipid quality as confirmed also by low values of Thrombogenic index (0.36, 0.30 and 0.22, respectively for L, S, R) and Atherogenic index (0.47, 0.42 and 0.33, respectively for L, S, R). Reared sharpsnout seabream showed lower saturated fatty acid values (26.44%, 32.21%, 34.85%, respectively for R, S, L) and higher oleic acid amount (21.61%, 19.15%, 11.99%, respectively for R, L and S). The subjects captured in the sea had a higher arachidonic acid content (5.44%, 1.76%, 0.59%, respectively for S, L, R). In the weight categories, the 100g subjects, showed higher incidence of viscera (VSI: 4.32%, 3.12% and 2.92%, respectively for 100, 200 and 300g) and liver (HIS: 2.20%, 1.97%, and 1.77%, respectively for 100, 200 and 300g), higher moisture (69.49%, 67.03%, 64.69%) and lower lipid rate (7.64%, 10.18%, 12.32%)

Effect of two different protein/fat ratios of the diet on meagre (<i>Argyrosomus regius</i>) traits

The aim of this study was to evaluate the effect of two diets with different protein/fat ratios (P/F) (diet A: P/F 2.26; diet B: P/F 3.36) on the chemical composition, fatty acid profile and some somatic indexes of meagre (Argyrosomus regius). The trial was carried out on two groups of meagre raised in two different sea cages during 15 months. At the end of the production cycle biometric measures as well as chemical-nutritional analysis of the fillets were conducted on 25 fishes per group. Diet A, with a lower P/F, furnished animals with higher percentages of mesenteric fat (0.48 vs 0.41%; P&lt;0.01) and of fillet yield (51.21 vs 48.12; P&lt;0.01). Moreover, the fillets obtained with the diet A showed higher percentage of fat (3.60 vs 2.41%; P&lt;0.01), lower moisture (74.10 vs 75.42%; P&lt;0.01), lower losses of water under pressure (16.73 vs 20.20%; P&lt;0.01) and after 48 h of refrigeration (3.08 vs 4.23%; P&lt;0.01). The fatty acids profile of fillets was affected by the diet. Diet A resulted in a higher level of saturated fatty acids (26.44 vs 23.17% of total lipid; P&lt;0.01) and a lower percentage of polyunsaturated fatty acids (31.56 vs 36.08%; P&lt;0.01) in the fillet, mainly due to the lower content of linoleic acid (13.63 vs 19.77%; P&lt;0.01). The atherogenic (AI) and thrombogenic (TI) indexes, which resulted very low in the fish of Group B (AI=0.48 vs 0.60, P&lt;0.01; TI=0.33 vs 0.37, P&lt;0.01), together with the low lipid content of meat in both groups, confirmed the very high nutritional quality of meagre fillets

Somatic indexes, chemical-nutritive characteristics and metal content in caught and reared sharpsnout seabream (<i>Diplodus puntazzo</i>)

The aim of this study was to compare some somatic indexes, chemical-nutritive characteristics and the contents of some metals (Pb, Cu, Cr and Zn) in the whole body and fillet from caught and reared sharpsnout seabream (Diplodus puntazzo). The fish came from three different conditions: reared in marine cages (R), captured in a natural lagoon (L) and in the Mediterranean sea (S). Thirty fish per group, divided into three weight categories (100±15.3, 200±18.7 and 300±20.4g), were used for the trial. Reared sharpsnout seabream showed higher amounts of celomatic fat (3.41%, 2.43%, 0.21%, respectively for R, L and S) and total lipid (13.86%, 11.23% and 5.06% respectively for R, L and S), and lower moisture (64.14%, 65.54%, 71.53%) and protein (17.73, 19.03 and 19.17%) than those caught in the lagoon and sea. The whole body of reared fish contained lower amounts of lead (0.70, 0.75 and 0.97mg/kg, respectively for R, L and S), copper (0.15, 0.38, 0.25mg/kg) chrome (2.19, 3.52, 3.77mg/kg) and higher zinc contents (63.47, 53.42, 47.31mg/kg) than caught fish. Fatty acids from sharpsnout seabream fillets showed a high lipid quality as confirmed also by low values of Thrombogenic index (0.36, 0.30 and 0.22, respectively for L, S, R) and Atherogenic index (0.47, 0.42 and 0.33, respectively for L, S, R). Reared sharpsnout seabream showed lower saturated fatty acid values (26.44%, 32.21%, 34.85%, respectively for R, S, L) and higher oleic acid amount (21.61%, 19.15%, 11.99%, respectively for R, L and S). The subjects captured in the sea had a higher arachidonic acid content (5.44%, 1.76%, 0.59%, respectively for S, L, R). In the weight categories, the 100g subjects, showed higher incidence of viscera (VSI: 4.32%, 3.12% and 2.92%, respectively for 100, 200 and 300g) and liver (HIS: 2.20%, 1.97%, and 1.77%, respectively for 100, 200 and 300g), higher moisture (69.49%, 67.03%, 64.69%) and lower lipid rate (7.64%, 10.18%, 12.32%)

Patterns of body condition use and its impact on fertility

A total of 60 nulliparous crossbred rabbit females were, a posteriori, divided into 2 experimental groups according to their natural “decision” to conceive or not at day 11 post first parturition (L: solely-lactating or LP: lactating-pregnant). This design allowed us to study the evolution of body reserves around first parturition and its influence on the future reproductive success of rabbit females. Primiparous rabbit females that failed to conceive when inseminated at day 11 post-partum (L) seemed to have a higher perirenal fat thickness (PFT) 12 d pre-partum (+0.25 mm; P=0.079) than females that conceived (LP). In the subsequent days, L females showed a significantly higher mobilisation rate than LP females (on av.–0.12 and –0.07 mm of PFT per day, respectively; P=0.007), reaching a lower PFT at partum (5.17 mm vs. 5.62 mm, respectively; P = 0.002). However, due to a greater recovery rate observed in L females (+0.15 vs. +0.08 mm of PFT per day for L and LP females, respectively; P=0.007), PFT at 10 d post-partum was similar (on av. 5.86 mm). These different patterns showed that PFT level at 12 d pre-partum and PFT mobilisation rate onwards seems to drive the start of a new pregnancy. It also seems to modify the energy metabolism of rabbit females, allowing does to recover perirenal fat tissue without compromising the production of milk necessary for the current litter.The authors acknowledge Juan Carlos Moreno for his technical support and the Spanish Ministry of Education and Science (Project AGL2014-53405-C2-1-P) for the economic support to conduct this study.Savietto, D.; Marono, S.; Martínez, I.; Martínez Paredes, EM.; Ródenas Martínez, L.; Cervera Fras, MC.; Pascual Amorós, JJ. (2016). Patterns of body condition use and its impact on fertility. World Rabbit Science. 24(1):39-45. https://doi.org/10.4995/wrs.2016.4006SWORD394524

MANNANOLIGOSACCARIDI COME ALTERNATIVA AGLI ANTIBIOTICI NELL'ALIMENTAZIONE DEL CONGILIO

Il periodo intorno allo svezzamento, risulta essere particolarmente delicato per i coniglietti, che si trovano a dover far fronte a forti stress, spesso causa di patologie enteriche che non di rado hanno un esito letale. La prevenzione di tali patologie, così come la cura, viene effettuata attraverso la somministrazione di antibiotici a scopo profilattico, ma lo smoderato utilizzo di questi farmaci, ha fatto nascere l’esigenza di limitarne l’uso, anche in seguito alla resistenza che batteri patogeni hanno mostrato nei confronti di tali medicamenti. In seguito al divieto sancito dalla Comunità Europea nel 2006, all’utilizzo degli antibiotici come promotori della crescita, è nata l’esigenza di ricercare molecole alternative che potessero sostituire gli antibiotici negli allevamenti zootecnici. Tra i rimedi alternativi agli antibiotici si annoverano probiotici, prebiotici, enzimi, acidi organici ed estratti vegetali. Nella presente tesi, sono stati condotti studi sui prebiotici, in particolare i mannano-oligosaccaridi, il cui meccanismo di azione si basa su una sorta di esclusione competitiva, in quanto numerosi batteri patogeni intestinali posseggono fimbrie di tipo 1, che sono specifiche per il mannosio e che determinano l’attacco ai mannosio-recettori sulle cellule intestinali. I mannani quindi possono impedire l’associazione mediata da fimbrie di tipo 1 alla mucosa intestinale legandosi alle fimbrie di questi microrganismi. I risultati ottenuti nelle varie prove sperimentali sopra riportate hanno evidenziato come i MOS possano rappresentare una valida alternativa agli antibiotici durante l’intero ciclo produttivo del coniglio da carne