Showing papers by "Cesare Castellini published in 2001"

Nutritional Quality of Rabbit Meat as Affected by Cooking Procedure and Dietary Vitamin E

Abstract: The effect of two dietary treatments (50 as opposed to 200 mg kg -1 of α-tocopheryl acetate) on rabbit meat, cooked by different procedures (boiling, frying, roasting), was evaluated. Cooking caused an increase of pH, shear force, lightness, hue and chroma, and a decrease of water holding capacity. The change in nutritional value was slight but lipid oxidation was increased and the fat quality worsened. Boiled meat had the lowest nutrient retention and the highest TBARS values. Supplemental vitamin E was effective in reducing oxidative processes and increasing the amount of n-3 polyunsaturated fatty acids also during cooking. Le but de cette etude est d'evaluer l'effet de la procedure de cuisson (bouillir, frire ou rotir) sur les qualites nutritionnelles de la viande de lapin et d'evaluer l'effet d'une supplementation alimentaire en α-tocopheryl acetate (50 a 200 mg/kg). La cuisson provoque une augmentation du pH, de l'effort tranchant, de la couleur et une diminution de la capacite de retention d'eau. Les modifications de la valeur nutritive sont faibles mais l'oxydation lipidique est augmentee et la qualite des matieres grasses degradee. La supplementation en vitamine E est efficace pour reduire les phenomenes oxydatifs.

Improvement of lipid stability of rabbit meat by vitamin E and C administration

Abstract: The effect of administering vitamins E (E50 or E200: 50 or 200 mg kg diet) and C (C500 or C1000: 500 or 1000 mg l−1 water) singly and in combination was verified on plasma and muscle levels of α-tocopherol and the oxidative stability of rabbit meat during display. Six groups of 10 hybrid males were fed experimental diets from 35 to 85 days of age. Productive performance and carcass drip loss were also recorded. Performance was unaffected by treatments, but drip loss was improved by simultaneous administration of the two antioxidants. The α-tocopherol levels in plasma and muscle were significantly higher in animals which simultaneously ingested the highest amounts of the two vitamins, and the oxidative processes (TBA-RS values) of their meat during storage were lower. The results confirm the synergistic action of ascorbate and the benefit of using high levels of the two vitamins to prevent oxidative stress during meat processing and storage. © 2000 Society of Chemical Industry

Isolation and purification of the IGF-I protein complex from rabbit seminal plasma: Effects on sperm motility and viability.

Abstract: A protein of about 150 kDa affecting sperm kinetic motility and viability was purified from rabbit seminal plasma. The incubation of rabbit sperm with this purified seminal plasma protein caused significant changes in sperm viability and motility. Moreover, the seminal protein showed a noticeable reactivating effect on immotile spermatozoa. A 10-mg amount of purified protein, added to immotile rabbit spermatozoa suspended in Tris-citrate, pH 7.4, resulted in a 48% reactivation. It is known that circulating insulin-like growth factors are bound to specific high-affinity binding proteins and form complexes with relative molecular masses of about 150 kDa. Western blotting analyses proved the existence of insulin-like growth factor in the protein purified from rabbit seminal plasma and immunofluorescence staining showed the existence of IGF-1 receptor in rabbit spermatozoa. Therefore, we suggest that the purified rabbit seminal plasma protein may represent the protein complex delivering IGF to the sperm cells thus affecting their physiological functions.

Effects of the purified IGF-I complex on the capacitation and acrosome reaction of rabbit spermatozoa.

Abstract: A protein complex containing IGF-I, purified from rabbit seminal plasma, was used to investigate its effects on the capacitation and acrosome reaction of rabbit spermatozoa. Uncapacitated sperm (Pattern F), capacitated sperm (Pattern B), and acrosome-reacted sperm (Pattern AR) were determined by CTC staining, and the results were validated by PSA-staining. The addition of the IGF-I complex to the capacitative medium directed the spermatozoa to spontaneous acrosome reaction. On the other hand, IGF-I complex, added to capacitated spermatozoa, acted as inducer of the acrosome reaction. Results of IVF experiments showed high rates of fertilization with capacitated spermatozoa, acrosome-reacted by either A23187 or IGF I complex, whereas significantly lower rates were obtained with spermatozoa capacitated in the presence of IGF-I complex. J. Exp. Zool. 290:311–317, 2001. © 2001 Wiley-Liss, Inc.

Effet du mode d'élevage (cage ou parc) sur l'évolution post mortem du pH et sur les caractères qualitatifs de la viande de lapin

Abstract: Les effets des conditions d'elevage sur la chute du pH et la qualite de la viande ont ete etudies sur 40 lapins repartis en 2 groupes homogenes, eleves differemment: en cage ou en parc. Les parametres analyses etaient les concentrations plasmatiques d'acide lactique et de glucose, le pH, l'acide lactique et le glycogene musculaires. La couleur et la capacite de retention en eau de la viande ont ete mesurees en parallele. Les lapins eleves en parc presentaient des niveaux d'acide lactique, de glucose et de glycogene plasmatiques et musculaires plus eleves que les animaux eleves en cage. Le pHu des muscles longissimus lumborum et biceps femoris a ete significativement plus faible chez les animaux eleves en parc que chez ceux eleves en cage. Au contraire, la capacite de retention en eau et les parametres de couleur n'ont pas ete affectes de maniere significative par le traitement.

Effet de l'addition des vitamines C et E sur les paramètres de la semence de lapin fraîche et après congélation

Abstract: On a procede a l'etude des effets des niveaux de surnutrition en vitamines E et C sur la qualite de la semence de lapin fraiche et congelee. Deux groupes homogenes de lapins adultes mâles NZW ont ete soumis a un regime alimentaire: l'un standard (50 mg/kg vitamine E), l'autre supplemente en vitamine E + C (200 mg/kg de vitamine E et 5 g/l d'eau de vitamine C). Apres une periode preliminaire de 6 semaines, de la semence a ete recoltee une fois/semaine pendant 21 jours. Les parametres analyses etaient les suivants: pourcentage de cellules vivantes et motiles, vitesse des spermatozoides (VCL), vitesse moyenne (VAP), linearite (LIN), amplitude de deplacement lateral de la tete (ALH), pourcentage de spermes capacites et de spermes avec acrosome reactif. Les caracteristiques de la semence fraiche n'ont pas ete affectees par le regime alimentaire, tandis que la semence congelee a connu des ameliorations significatives. Les animaux supplementes presentaient une semence avec une meilleure VCL, un pourcentage plus eleve de cellules motiles et vivantes et de spermes capacites.