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The present study compared behaviour, fear and stress levels of 456 crossbred rabbits reared in bicellular wire-net cages (2 rabbits/cage) with top and wire floor or open-top collective pens (20 to 54 rabbits/pen) with wooden slatted floor. The effect of pen size (small vs. large) and stocking density (12 vs. 16 rabbits/m2) in collective pens was also evaluated. The rabbits kept in collective pens rested more than those in bicellular cages (82.1% vs. 77.6% of observed time; P

The aim of this study was to compare the growth performance, slaughter results, and carcass and meat quality of rabbits reared in different housing systems. To this purpose, 456 Hyplus crossbred rabbits were reared from weaning (35 d of age) until slaughter (77 d) in 40 bicellular wire net cages (28×40×28 cm3; 2 rabbits/cage; 18 animals/m2); 4 small collective pens (1.40×1.20 m2) at low stocking density (20 rabbits/pen; 12 animals/m2); 4 small collective pens at high stocking density (27 rabbits/pen; 16 animals/m2); 2 large collective pens (1.40×2.40 m2) at low stocking density (40 rabbits/pen; 12 animals/m2); and 2 large collective pens at high stocking density (54 rabbits/pen; 16 animals/m2). The housing of rabbits in collective pens decreased final live weight (2839 vs. 2655 g; P

The biometric and nutritional traits of European sea bass from organic or semi-intensive conventional production systems at two commercial sizes (small and medium) were compared. The analysis included a total of 80 specimens. The biometric traits and the texture were not affected by the rearing system, whereas they changed significantly with fish size. The fillet fatty acid profile varied significantly, both with rearing system and sea bass size, depending on the fatty acid profile of the diets. The ratio of n − 3 to n − 6 polyunsaturated fatty acids was higher ( p

According to classical genetic studies, piebaldism in cattle is largely influenced by the allelic series at the spotting locus (S), which includes the S(H) (Hereford pattern), S(+) (non-spotted) and s (spotted) alleles. The S locus was mapped on bovine chromosome 6 in the region containing the KIT gene. We investigated the KIT gene, analysing its variability and haplotype distribution in cattle of three breeds (Angus, Hereford and Holstein) with different putative alleles (S(+), S(H) and s respectively) at the S locus. Resequencing of a whole of 0.485 Mb revealed 111 polymorphisms. The global nucleotide diversity was 0.087%. Tajima's D-values were negative for all breeds, indicating putative directional selection. Of the 28 inferred haplotypes, only five were observed in the Hereford breed, in which one was the most frequent. Coalescent simulation showed that it is highly unlikely (P < 10E-6) to obtain this low number of haplotypes conditionally on the observed number of segregating SNPs. Therefore, the neutral model could be rejected for the Hereford breed, suggesting that a selection sweep occurred at the KIT locus. Twelve haplotypes were inferred in Holstein and Angus. For these two breeds, the neutral model could not be rejected. High heterogeneity of the KIT gene was confirmed from a phylogenetic analysis. Our results suggest a role of the KIT gene in determining the S(H) allele(s) in the Hereford, but no evidence of selective sweep was obtained in Holstein, suggesting that complex mechanisms (or other genes) might be the cause of the spotted phenotype in this breed.

The objective of this study was to investigate the association of DNA markers in candidate genes for glycolytic potential on meat quality parameters (pH1, pHu, glycogen and lactate content and glycolytic potential of semimembranosus muscle) and estimated breeding values (EBVs) for average daily gain, lean cuts, back fat thickness, ham weight, and feed:gain ratio in 272 Italian Large White pigs. Three mutations in the PRKAG3 gene (T30N, G52S and I199V) were investigated as well as single nucleotide polymorphisms in two other skeletal muscle genes (PGAM2 and PKM2) involved in the glycolytic pathway. Association analysis with the PRKAG3 markers showed significant results (P < 0.05) only for pH1 (I199V, with significant additive effect) and lactate content (T30N), confirming, at least in part, the effects of this gene on meat quality traits. Significant association (P < 0.05) was also observed for PGAM2 and ham weight EBV with significant additive and dominance effects. PKM2 was associated with average daily gain, lean cuts (P < 0.001), back fat thickness and feed:gain ratio (P < 0.05), with significant additive and/or dominance effects on these traits. PKM2 encodes for a key enzyme of the muscle glycolytic pathway and maps on porcine chromosome 7 where other studies have reported important QTL for the same traits. These data might suggest an important function of this gene in the mechanisms that produce the observed effects. The results will be important to evaluate the inclusion of some of these DNA polymorphisms in marker assisted selection programs.

We sequenced almost the complete coding region of the MC1R gene in several domestic rabbits (Oryctolagus cuniculus) and identified four alleles: two wild-type alleles differing by two synonymous single nucleotide polymorphisms (c.333A>G;c.555T>C), one allele with a 30-nucleotide in-frame deletion (c.304_333del30) and one allele with a 6-nucleotide in-frame deletion (c.280_285del6). A polymerase chain reaction-based protocol was used to distinguish the wild-type alleles from the other two alleles in 263 rabbits belonging to 37 breeds or strains. All red/fawn/yellow rabbits were homozygous for the c.304_333del30 allele. This allele represents the recessive e allele at the extension locus identified through pioneering genetic studies in this species. All Californian, Checkered, Giant White and New Zealand White rabbits were homozygous for allele c.280_285del6, which was also observed in the heterozygous condition in a few other breeds. Black coat colour is part of the standard colour in Californian and Checkered breeds, in contrast to the two albino breeds, Giant White and New Zealand White. Following the nomenclature established for the rabbit extension locus, the c.280_285del6 allele, which is dominant over c.304_333del30, may be allele E(D) or allele E(S).

At 34 days of age, 376 crossbred rabbits of both sexes were housed in 16 open-top collective pens (1.68 m2) according to a 2×2×2 factorial arrangement with two types of pen floor (plastic v. wooden slatted), two stocking densities (12 v. 16 animals/m2) and two slaughter ages (76 v. 83 days). The rabbits were examined for growth performance, slaughter results and meat quality. The effect of gender was also examined. The percentage of rabbits with wounds due to aggression varied with stocking density (8.2% v. 26.2% for 12 v. 16 animals/m2; P⩽0.001), slaughter age (15.0% v. 22.0% at 76 v. 83 days; P⩽0.10) and gender (11.3% v. 25.8% for females v. males; P⩽0.001). Rearing rabbits on a plastic rather than a wooden slatted floor promoted slaughter weight (2795 v. 2567 g; P⩽0.001), dressing percentage (61.4% v. 60.9%; P⩽0.01), dissectible fat (2.4% v. 2.0%; P⩽0.01) and hind leg muscle-to-bone ratio (5.81 v. 5.35; P⩽0.001). Increased stocking density impaired daily growth (38.5 v. 35.9 g/day; P⩽0.05) and feed intake (140 v. 134 g/day; P⩽0.01) during the second period (55 days to slaughter) and decreased slaughter weight (2725 v. 2637 g; P⩽0.01). At the older slaughter age, the feed conversion ratio was impaired (2.98 v. 3.18; P⩽0.001); the slaughter weight (2574 g v. 2788 g; P⩽0.001), dissectible fat (2.0% v. 2.4%; P⩽0.01) and hind leg muscle-to-bone ratio (5.41 v. 5.75; P⩽0.01) increased; meat thawing losses, cooking losses and shear force decreased (P⩽0.05). The main differences between the females and males were found in the slaughter for transport losses (2.6% v. 2.2%; P⩽0.01) and longissimus lumborum proportions (13.0% v. 12.4%; P⩽0.01). In conclusion, the growth performance of pen-housed rabbits was largely determined by the type of floor and less affected by stocking density. The meat quality depended on ontogenetic factors, such as slaughter age and gender, and not on housing conditions. The differences in the percentages of wounded animals owing to experimental factors deserve further investigation from the perspective of animal welfare issues.

A total of 282 crossbred rabbits of both genders were divided into six experimental groups and fed ad libitum six diets formulated in a 2×3 factorial arrangement based on three dietary energy levels (low, approximately 8.45 MJ/kg; medium, 9.9 MJ/kg: and high, 11.5 MJ/kg) and two crude protein levels (15% and 17%). The increase of dietary energy was obtained by a simultaneous increase of dietary starch (9.1%, 13.7%, and 17.9%) and soluble fibre (4.8%, 7.1%, and 9.4%) at the expense of acid detergent fibre (23.0%, 18.0%, and 13.5%). Growth performance and nitrogen excretion from weaning until slaughter, and digestive traits were monitored. The increase of dietary energy enhanced the apparent digestibility of dry matter (50.8%, 60.5%, and 71.5%; P

From 29 d of age until slaughter (78 d), 246 hybrid rabbits were divided into six experimental groups and fed six diets ad libitum according to a bi-factorial arrangement with two soluble fibre-to-starch ratios (0.5 and 1.1), obtained by replacing starch (from 178 to 130 g/kg) with soluble fibre (from 84 to 141 g/kg), and three levels of crude protein (139, 154, and 172 g/kg diet). Growth traits were recorded on all rabbits; total tract apparent digestibility coefficients (CCTAD) were measured on 72 rabbits. Gut traits were obtained from further 36 rabbits slaughtered at 38 d of age. The increase in the soluble fibre-to-starch ratio increased (P

During growth (27 to 75 days of age), a total of 384 rabbits were kept in 72 individual cages, 48 bicellular cages (2 rabbits/cage) and 24 collective cages (9 rabbits/cage). To evaluate the effects of the housing system on the fear level and behavioural patterns of rabbits at the two ages (39 to 45 days and 66 to 73 days), a tonic immobility test and an open-field test were conducted and their behaviour was video recorded. In the tonic immobility test, the number of attempts to induce immobility (1.38) was lower, and the duration of immobility (47.8 s) was higher (0.05 < P < 0.01) in the rabbits housed in individual cages than in those kept in bicellular (1.72 attempts and 25.0 s of immobility) and collective cages (1.99 attempts and 25.0 s of immobility). During the open-field test, the rabbits from individual and bicellular cages showed higher latency (38.8 and 40.3 v. 27.0 s), a lower number of total (73.3 and 81.7 v. 91.9) and central displacements (3.6 and 2.8 v. 5.4) and a shorter running time (11.8 and 13.6 s v. 17.7 s) and the time biting the pen (5.5 and 9.1 s v. 28.2 s) compared with the rabbits kept in collective cages (0.05 < P < 0.001). During the 24-h video recording, the rabbits in individual and bicellular cages spent less time allogrooming (0.34% and 0.19% v. 1.44%), moving (0.74% and 0.60% v. 1.32%) and running (0.08% and 0.03% v. 0.21%) than the rabbits in the collective cages (0.01 < P < 0.001). The lowest numbers of alerts and hops were observed in the rabbits kept in bicellular cages. With increasing age, a lower number of rabbits were sensitive to the immobility test and more rabbits entered the pen spontaneously during the open-field test (P < 0.001). In conclusion, the rabbits in individual cages exhibited the highest fear level and incomplete behavioural patterns; the rabbits housed in collective cages showed the lowest fear levels and had the possibility of expressing a wider range of behaviour; and the rabbits in bicellular cages exhibited an inconsistent pattern of fear in the tonic immobility and open-field tests. Probably, these rabbits were in a less stressful condition compared with animals in individual cages because social contacts were allowed, even if freedom of movement was more limited.

The study evaluated the levels of dioxin-like polychlorinated biphenyls (DL-PCBs) and metals in the fillet of medium (468 ± 92 g) and large (708 ± 135 g) European sea bass (Dicentrarchus labrax) from 11 Italian fish farms using different rearing systems. DL-PCB contamination was higher in fish grown in extensive coastal lagoons compared with intensive inland basins and intensive sea cages (28.5 vs. 9.13 and 13.1 pg Toxic Equivalents (TEQ)/g fat; P < 0.001). Copper concentrations were lower (0.810 vs. 0.993 and 1.071 mg/kg fw) and mercury was higher (0.025 vs. 0.006 and 0.003 mg/kg fw) (P < 0.001) in sea bass from extensive farms than from intensively farmed fish in inland or sea cage systems. Sea bass size did not affect DL-PCB and metal contamination. Even at the highest contamination levels detected in this study, European sea bass were always below risk for human health concerns and were considered safe for human consumption.

In mammals, abnormal migration of melanoblasts from the neural crest during embryonic development may be the reason of the pielbaldism phenotype that is a mixture of pigmented and unpigmented areas...

Farmed European sea bass (Dicentrarchus labrax), sampled from three different culture systems (intensive in sea-cages, intensive in land-based basins and extensive in lagoon and storage basins of salt-work), of the Northern, Central and Southern Italy, were analyzed with the aim to employ nutritional trait to describe and to distinguish the “origin” of the product. Lipid and fatty acid profile, strongly affected by the feeding history and environmental factors, responsible of the nu- tritional and perceived quality of fish product, are proposed as marker of origin.

[EN] Simple and non-invasive methods of collecting and preserving biological specimens for genetic analysis can be useful in reducing the discomfort of the involved animals and can be applicable for highthroughput studies that require a large number of biosamples. In order to have the possibility to analyse a large number of samples and making easier the collection of rabbit biological materials as well as to reduce the cost and time of the genotyping procedures, here we tested different protocols for the genotyping of mutations identified in the rabbit melanocortin receptor 1 (MC1R) gene that are associated to coat colours in different rabbit breeds. These protocols make use of rabbit hair roots or cell preparations from buccal swabs with a direct PCR amplification without previous DNA extraction. Hair samples were collected from 60 rabbits of different breeds and preserved for up to 12 months at 4°C. For each hair sample 5-10 hair roots were clipped a few mm from the root directly within a 0.2 ml PCR tube. Buccal cells were collected from 10 crossbred and purebred rabbits and prepared after a few steps for PCR. The PCR fragments were analysed by means of polyacrylamide gel electrophoresis and stained with ethidium bromide or using fluorescent labelled products resolved in a capillary automatic sequencer. The success genotyping rate of the hair and buccal cell samples was 98% and 80%, respectively. These values are comparable to the success rates of other protocols described in human or other animals involving previous DNA extraction. The obtained results show that noninvasive methods of biological specimen collection that make it possible to analyse the DNA without previous extraction can be easily and routinely applied in rabbit molecular genetic studies. However, due to the higher success rate and the easier method of collection, plucked hairs seem the best source for high-throughput biosampling in this species., This work was supported by RFO funds from the University of Bologna. We thank several rabbit breeders and Associazione Nazionale Coniglicoltori Italiani (ANCI) for their collaboration in the sampling of biological materials

Una mutazione puntiforme nell’esone 8 del gene del recettore dell’ormone della crescita (GHR), che cambia l’aminoacido fenilalanina in tirosina in posizione 279 (F279Y), è stata indicata avere un effetto positivo sulla percentuale di proteina del latte (allele F) o sulla quantità di latte (allele Y). Fino ad ora nessun dato relativo alla distribuzione di questi due alleli era disponibile in alcuna razza bovina e per questo nel presente studio abbiamo analizzato le frequenze alleliche di questo polimorfismo in alcune razze bovine da latte e a duplice attitudine allevate in Italia. Campioni di latte, peli e seme sono stati collezionati da 679 animali appartenenti a sette razze diverse (Frisona Italiana, n=108; Bruna Italiana, n=104; Pezzata Rossa Italiana, n=104; Jersey, n=104; Reggiana, n=108; Modenese, n=66; Rendena, n=85). Per l’analisi della mutazione F279Y del gene GHR è stato messo a punto un protocollo basato sulla tecnica di PCR-RFLP con un primer forward modificato, che inserisce nel frammento di DNA amplificato un sito di taglio artificiale per l’enzima di restrizione SspI. Per confermare i risultati dell’analisi PCR-RFLP, è stato sequenziato un frammento di del gene di 381 pb ottenuto da bovini con diverso genotipo. In tutte le razze analizzate l’allele F è risultato il più frequente con un valore massimo di circa il 95% nella Bruna Italiana e nella Jersey ed un valore minimo di circa il 73% nella Frisona Italiana. Nelle razze Rendena, Pezzata Rossa Italiana, Reggiana e Modenese la frequenza di questo allele è risultato, rispettivamente dell’82%, 91%, 92% e 92%. I dati ottenuti non hanno rilevato alcun scostamento statisticamente significativo dall’equilibrio di Hardy-Weinberg. Le frequenze alleliche della Frisona Italiana e della Rendena sono risultate essere significativamente (rispettivamente P

l legame tra un prodotto di origine animale e la razza da cui questo è originato rappresenta un aspetto importante per la valorizzazione di alcune produzioni. Il maggior prezzo che questi prodotti spuntano sul mercato fa emergere l’esigenza di poter autenticare o tracciare i prodotti mono-razza per smascherare e scoraggiare possibili frodi. A questo scopo sono stati proposti sistemi di analisi del DNA, alcuni dei quali utilizzano marcatori in geni che determinano il colore del mantello, che è uno dei principali caratteri che differenziano tra di loro le razze. Diverse mutazioni nel gene melanocortin 1 receptor (MC1R) sono già state associate a particolari effetti sul colore del mantello nella specie bovina. In questa ricerca abbiamo studiato la presenza dei principali alleli al locus MC1R, per valutare la possibilità di utilizzare questo gene per l’autenticazione e la tracciabilità di razza dei prodotti lattiero-caseari. Le mutazioni che permettono di distinguere questi alleli sono state analizzate utilizzando protocolli di PCR-RFLP e PCR-APLP su un totale di 1360 animali appartenenti a 18 razze bovine. Per ognuna delle seguenti razze, Frisona Italiana, Bruna Italiana, Pezzata Rossa Italiana, Jersey, Rendena, Reggiana e Modenese, è stato possibile analizzare più di 70 animali. L’allele Ed è stato identificato nella razza Frisona Italiana con una frequenza dello 0,886. L’allele E (nomenclatura che include tutti gli alleli tranne che e, Ed e E1) è stato identificato con alta frequenza nella Bruna Italiana (0,591), Rendena (0,738), Jersey (0,955) e Modenese (0,961) e con bassa frequenza nella Pezzata Rossa Italiana (0,029). Inoltre, questo allele è stato osservato nella Rossa Svedese, Rossa Danese, Grigio Alpina, Piemontese, Romagnola, Marchigiana e Chianina. In alcune di queste razze (Bruna Italiana, Rendena, Grigio Alpina, Piemontese, Rossa Svedese e Rossa Danese) è stato identificato anche l’allele E1. L’allele e è risultato fissato nella razza Reggiana e quasi fissato nella razza Pezzata Rossa Italiana. Inoltre, con bassa frequenza, è stato identificato in tutte le altre razze analizzate, tranne che nella Marchigiana. Le differenze osservate tra razze esaminate indicano che, almeno in alcuni casi, è possibile utilizzare i polimorfismi del gene MC1R per escludere o confermare l’impiego di latte di una determinata razza nella produzione di un prodotto lattiero-caseario. Il caso più interessante è quello del formaggio Parmigiano Reggiano prodotto con l’uso esclusivo di latte di bovine di razza Reggiana. Infatti, essendo presente in questa razza soltanto l’allele e il rilievo analitico di qualsiasi altro allele nel DNA estratto dal formaggio rivela l’uso di latte proveniente da altre razze. La messa a punto di un metodo PCR-RFLP per l’analisi del DNA estratto da prodotti lattiero caseari, incluso il Parmigiano Reggiano di oltre 24 mesi di stagionatura, rappresenta uno strumento importante per la difesa di questo prodotto mono-razza da eventuali frodi. I risultati ottenuti su 10 forme di formaggio prodotto esclusivamente con latte di bovine di razza Reggiana e su 15 forme di Parmigiano Reggiano commerciale ottenuto senza restrizione della razza di origine del latte hanno mostrato la validità del metodo del quale è stata valutata anche la sensibilità n cattle, the MC1R gene has been the subject of several studies with the aim to elucidate the biology of coat colour. Then, polymorphisms of this gene have been proposed as tools for breed identification and animal products authentication. As a first step to identify breed specific DNA markers that can be used for the traceability of mono-breed dairy cattle products we investigated, using PCR-RFLP and PCR-APLP protocols, the presence and distribution of some alleles at the MC1R locus in 18 cattle breeds for a total of 1360 animals. For each of seven breeds (Italian Holstein, Italian Brown, Italian Simmental, Rendena, Jersey, Reggiana and Modenese) a large number of animals (>70) was genotyped so the obtained results can be considered with more confidence. Allele Ed was identified only in black pied cattle (Italian Holstein and Black Pied Valdostana). Allele E (this nomenclature includes all alleles except Ed, E1 and e) was observed in Italian Brown, Rendena, Jersey, Modenese, Italian Simmental, Grigio Alpina, Piedmontese, Chianina, Romagnola, Marchigiana, Swedish Red and White and Danish Red. Allele E1 was identified in Italian Brown, Rendena, Grigio Alpina, Piedmontese, Swedish Red and White and Danish Red. The recessive allele e, known to cause red coat colour, was fixed in Reggiana and almost fixed in Italian Simmental. This allele was observed also in Italian Holstein, Italian Brown, Rendena, Jersey and Modenese albeit with low frequency. Moreover, this allele was detected in Valdostana, Pezzata Rossa d’Oropa, Piedmontese, Romagnola, Swedish Red and White, Danish Red, Charoleis and Salers. In the case of the Reggiana breed, which is fixed for allele e, the MC1R locus is highly informative with respect to breeds that carry other alleles or in which allele e is at very low frequency. In theory, using the MC1R locus it is possible to identify the presence of milk from some other breeds in Parmigiano Reggiano cheese labelled as exclusively from the Reggiana breed. This possibility was practically tested by setting up protocols to extract and analyse polymorphisms of the MC1R locus in several dairy products, including Parmigiano Reggiano cheese cured for 30 months. The lower detection limit was estimated to be 5% of non expected DNA. This test can represent a first deterrent against fraud and an important tool for the valorisation and authentication of Parmigiano Reggiano cheese obtained from only Reggiana milk.