22 research outputs found
Effetto del temporaneo impiego dell'acqua reflua decantata sulle prestazioni produttive in vivo e la sopravvivenza dell'orata (Sparus aurata) in fase d'ingrasso
Con questo studio si è voluto testare la possibilità di utilizzare in un nuovo ciclo di produzione dell’orata (Sparus aurata), l’acqua reflua di vasche d’allevamento dopo una fase di decantazione in un apposito bacino di lagunaggio. Pesci di circa 240 g, al sesto mese di ingrasso, sono stati distribuiti in due vasche di 208 m3, alimentate una con acqua di mare e l’altra con acqua reflua decantata. Per valutare gli effetti sulle prestazioni produttive in vivo e la sopravvivenza delle orate sottoposte per 137 giorni a tale sistema di allevamento è stato rilevato, giornalmente, la quantità di mangime somministrato ed il numero dei pesci morti per vasca. Inoltre, a cadenza di 45 giorni una dall’altra, sono state effettuate 4 campionature deipesci e dell’acqua in entrata.
Nell’intero periodo di sperimentazione, la mortalità nelle due vasche è stata simile (meno del 2%) e il peso medio delle orate campionate ad ogni rilevamento è risultato statisticamente uguale. L’indice di conversione alimentare è stato pari a 2,1 per la vasca decantata ed a 2,8 per la vasca di controllo. Nel complesso le perfomances produttive delle orate sono risultate soddisfacenti evidenziando una buona adattabilità della specie ad un temporaneo allevamento con acqua reflua decantata
Observations on the embryonic development of domestic meat-type guinea fowl (Numida meleagris)
Guinea fowl breeding for meat production is widespread across Europe and the USA. For hatcheries to achieve their output potentials, they need in-depth knowledge about incubation techniques and guinea fowl embryonic development. The aim of this study was to provide updated quantitative data on the developing meat-type strain embryo and to describe its embryonic growth pattern in terms of embryonic weight modelled using Gompertz and logistic functions. Eggs from a 56-week-old genetically controlled flock (Galor S.A.S., Amboise, France) were individually weighed and incubated according to good hatchery practices. 10 embryos were randomly removed every 12 h through to hour 192 of incubation, and thereafter every 24 h. Incubation traits, blastoderm diameter, vitelline circulation diameter, and embryo body weight were recorded, and the mean daily wet embryo-specific mass was calculated. During each session, photographic documentation of the embryos was also obtained, including a general view of the egg content as well as the isolated embryonic body. Embryonic growth curves were estimated using Gompertz and logistic functions, and their parameters are given. High fertility (96%) and hatchability (81%) rates were observed, and the mean keet weight was 32 g at hatch. The accuracy of the curve fit was high for both models. The curves’ inflection points occurred on days 21 and 23 for the logistic and Gompertz models, respectively, demonstrating an embryonic growth pattern typical of a precocial bird species. A photographic chart of the in-ovo chronological development of guinea fowl is provided.HIGHLIGHTS The study follows the incubation and embryonic development of meat-type guinea fowl (Numida meleagris). Daily photographic images and graphical growth models of body weight document the birds’ embryonic development. The results provide effective practical help for hatchery practices by enabling the determination of embryo age
Tear production, intraocular pressure, ultrasound biometric features and conjunctival flora identification in clinically normal eyes of two italian breeds of chicken (Gallus gallus domesticus)
Given the abundance of chickens in Italy, it is important for veterinarians to know the normal state of chickens’ eyes in order to identify any ophthalmic pathological changes. The aim of this study was to determine the normal values of select ocular parameters and to evaluate conjunctival microflora in two Italian chicken breeds. Sixty-six healthy chickens underwent a complete ophthalmic examination, which included a phenol red thread test (PRTT) for the evaluation of tear production and the assessment of intraocular pressure by rebound tonometry. B-mode ultrasound biometric measurements and conjunctival microflora identification were also performed in twenty-seven chickens. Mean PRTT was 23.77 ± 2.99 mm/15 s in the Livorno breed and 19.95 ± 2.81 mm/15 s in the Siciliana breed. Mean intraocular pressure was 14.3 ± 1.17 mmHg in the Livorno breed and 14.06 ± 1.15 mmHg in the Siciliana breed. Reference ranges for morphometric parameters were reported in the two breeds. Twenty-three chickens (85.18%) were bacteriologically positive. Chlamydia spp. antigen was detected in 14.81% of chickens. No positive cultures were obtained for fungi. Normal reference range values for selected ophthalmic parameters were obtained in clinically healthy chickens, which could facilitate accurate diagnosis and better management of ophthalmic diseases in these animals
Italian semen cryobank of autochthonous chicken and turkey breeds: a tool for preserving genetic biodiversity
The creation of genetic resource cryobanks provides a crucial link between in situ and ex situ techniques to improve the efficiency of conservation programs. Aim of the present review is to describe all the activities developed for the implementation of the first Italian Semen Cryobank of Autochthonous Chicken and Turkey Breeds. These activities can be classified into three main topics: (1) identification of species-specific semen freezing/thawing reference procedures; (2) drafting Standard Operative Procedures (SOP) for the implementation of the semen cryobank; (3) storage of semen doses from Italian chicken and turkey breeds to establish the cryobank. Several trials have been developed to identify a specie-specific semen cryopreservation protocol for chickens and turkeys. The major results are reviewed and a final reference protocol described. Taking into consideration the FAO guidelines for cryoconservation of animal genetic resources, SOP were drafted with the aim to provide technical guidance and logistical support on the choice of priority breeds, selection of birds for semen production, infrastructures and storage sites, birds and semen management, cryopreservation process and doses traceability. Lastly, the Italian Semen Cryobank was created. A total of 112 semen doses from 22 cockerels of three breeds, and 74 doses from 12 turkey males of three breeds were stored in the Cryobank. Breed specific semen quality parameters assessed before and after cryopreservation are reported. The described activities provide information and tools useful for the implementation of semen cryobanking in avian species and might be transferred also to other species after appropriate adaptations.HIGHLIGHTS Implementation of the first Italian Semen Cryobank of Autochthonous Chicken and Turkey Breeds Drafting Standard Operative Procedures provides technical guidance and logistical support on the design and establishment of the cryobank Semen cryobank is a precious genetic reservoir and could be useful to safeguard genetic variability in small population in vivo conserved
Manganese-bearing beraunite from Mangualde, Portugal: mineral data and structure refinement
A Mn-bearing oxidized variety of beraunite occurs in a phosphatic nodule in a granite at Mangualde, Portugal. It forms sheaf-like aggregates of subparallel needles. The elongated prisms have a rhombic section. The prevalent forms are (301) and (30-1) (both closely striated) and, in cases, a very thin (001). Mn-bearing beraunite is red, vitreous and transparent. Dmeas 2.99 g/cm3. Optically it is biaxial (+) with (-) elongation: orientation Y=b, X:c = +10°, 2Vz = 78(2)°, with medium dispersion of 2Vz, r > v, indices of refraction alphacalc 1.768, betameas 1.774, gammacalc 1.783. Pleochroism X = Y pale yellow, Z red orange. Chemical analysis by ICP gives: Li2O 0.02, Na2O 0.15, CaO 0.17, MnO 4.23, FeO 0.01, Fe2O3 49.49, P2O5 31.62, H2O 15.38, total 101.07 wt.%, leading to the formula Fe3+5.65Mn0.54Na0.04Ca0.03Li0.01 (OH)5(PO4)4.06(OH)0.95(H2O)4.81. Mn-bearing beraunite is monoclinic, space group C2/c, with a 20.760(3), b 5.154(1), c 19.248(2) Å, beta 93.55(1)°, V 2055.4(3) Å3 and Z = 4. The strongest reflections in an X-ray powder diffraction pattern [d in Å (Iobs) (hkl)] are: 10.39(vS)(200), 9.62(vs)(002), 7.28(S)(-202), 4.82(mS)(111), 3.081(S)(314). Eighteen previously unobserved reflections were recorded. The structure of the Mn-bearing beraunite has been refined to an R of 0.034 and an Rw of 0.029 for 2690 observed [I>3sigma(I)] reflections. Hydrogen bonding is proposed, based on the refined positions of hydrogen atoms. Mn2+ partially substitutes for Fe3+ in the Fe1 and Fe2 sites
Muscovy and common duck: effect of system of breeding on slaughtering traits and meat quality
Since meat quality is actually of great importance in Europe and open air rearing systems are preferred by the consumers, the authors evaluated the slaughtering traits of Muscovy and common ducks reared under different techniques (rearing period: whole inside a poultry house or finisher period at open air) Results showed that the system which presumes a finisher period at open air really determines differences in carcass traits and meat quality of both the studied ducks. However, the carcasses of the Muscovy ducks showed better traits than the carcasses of the common ducks, independently from the rearing technology adopted
Observations on the sexual behaviour of muscovy duck
The sexual behaviour of Muscovy duck (Cairina moschata domestica L.) was compared with the interspecific mating pattern of male Muscovy x female game-farm Mallard (Anas platyrhynchos) and of the reciprocal cross, to see whether behaviour differences may partly account for the low fertility in the interspecific crosses. In this study we also compared the interspecific sexual behaviour of animals which cohabited for a brief or a long period. From the study it appears that there are some evident behavioural differences between these two species that sometimes prevent mating. If ducklings of both species are raised together, a better understanding between the partners seem to be. While a prolonged cohabitation, starting from sexual maturity did not affect the behaviour of mating
Tecnologia di allevamento del fagiano: riproduzione in colonia o in famiglia.
E' stato valutato l'effetto della diversa tecnica di allevamento in famiglia e in colonia sull'efficienza riproduttiva del fagiano. Per la prova sono stati utilizzati 236 fagiani riproduttori e sono state formate le famiglie (1 maschio e 7 femmine) e le colonie (7 maschi e 45 femmine). La tecnica di allevamento in colonia aumenta la resa delle uova deposte. La presenza di piĂą maschi non aumenta significativamente la mortalit
Meat quality of Italian strains of Muscovy, Common and MuscovyxCommon duck bred under two different
The meat quality of ducks were studied in relationship to two different rearing technologies(whole inside a poultry house; the first period in poultry house and the second period, from 29 days to slaughtering age, in pens at open air. Muscovy ducks and Common ducks were used for the trial. a sample of each species, reared under the two systems, was slaughtered (11 weeks MD males, 9 weeks MD females, 8 weeks both sexes of CD and 10 weeks mulards). Results showed that the system which imposed the open air period did not determine a reduction of growth speed, on the contrary males and Mulards improved their growth. No statistical differences were observed between slaughtering traits in relationship to the systems of rearing. Mulards showed carcass traits more similar to MD males (ready to cook carcass incidence was 63%, 65% and 58% in mulards, in MD males and in both sexes of CD, respectively). Breast muscles rate was higher in mulards than MD males, MD females and both sexes of CD (23% vs 20%, 17% and 17-18%) Abdominal fat incidence decreased with age and at traditional slaughtering ages was very low: mulards 0,8%, MD females 2,7%, MD males 1,5%, CD 1,3-2,2 %. dry matter of breast muscle was higher in mulards than in MD and CD. Shear force was lower in mulards than in all other species