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Fievez, V., Piattoni, F., Mbanzamihigo, L. and Demeyer, D. 1999. Reductive acetogenesis in the hindgut and attempts to its induction in the rumen—A review. J. Appl. Anim. Res., 16: 1–22. Hindgut fermentation differs from rumen fermentation by a lower methane production and the presence of reductive acetogenesis (RA). Moreover, it has been shown that with ageing RA is replaced completely (rumen) or partially (hindgut) by methanogenesis (M). In some animals, as well as in humans, the importance of M has been related to a genetic predisposition, although from results obtained with rabbit caecal contents, this remains questionable. Former results suggested the importance of easily fermentable substrate for RA, more specific recent data suggest a promoting effect for homoacetogenic growth. In a second part of the paper attempts to induce RA in the rumen are reviewed. Neither addition of free amino acids, mucins, hydrogenotrophic substrates or bile salts were able to stimulate RA during batch incubatio...

Effects of bromoethansulfonic acid (2-BES) and monensin (M) on caecal fermentation pattern of fasted (F) and non-fasted (NF) rabbits (14 in total), were studied using in vitro batch incubations. In the first experiment, caecal contents were collected from 4 F (24 h) and 4 NF conventional rabbits (70–77 days old). They were incubated for 24 h at 39°C under 100% CO 2 or 50% CO 2 +50% H 2 atmosphere with 2-BES (1–20 mM) and monensin (50 mg/kg) and net production of volatile fatty acids (VFA) and methane (CH 4 ) was measured and hydrogen recoveries (2Hr) calculated. In fasted rabbits, 2-BES addition (1 mM) caused a slight decrease in CH 4 (14%) without changing the fermentation pattern whereas M caused a decrease in CH 4 (51%) accompanied by a decrease in total VFA production (29%), mainly butyrate (B) (37%) and acetate (A) (33%). In NF rabbits, 2-BES (20 mM) depressed CH 4 (93%) while M induced a surprising increase in CH 4 (56%) coupled to a decrease in total VFA (16%), mainly B (34%). The consequent increase (31%) in the calculated hydrogen recoveries (2Hr) was hypothesized to be due to a decrease in acetogenic and reductive acetogenic bacteria. In the second experiment, hydrogen gas addition to caecal contents from 3 NF rabbits increased total VFA production (12%), mainly butyrate (32%) and monensin induced an increase in CH 4 production (33%) and changed the fermentation pattern towards lower total VFA, lower B and higher P. As microbial counts did not reveal a decrease in acetogenic and reductive acetogenic bacteria when monensin was added, it was hypothesized that the increase in CH 4 was due to a depression of their autotrophic activity, leaving more H 2 available for methanogenesis and reductive acetogens survived than heterotrophically.

In order to study the age dependent variation of caecal contents composition, a young rabbit was slaughtered out of 6 conventional litters at the age of 22; 25; 28; 32; 36; 42 and 56 days. Rabbits were fed a standard diet before and after weaning (at 28 days of age). Daily growth and caecum size were determined. Caecal contents were analyzed for dry matter (DM), pH, crude protein (CP), neutral detergent fibre (NDF), ribonucleic acid (RNA), lactate, ammonia nitrogen and volatile fatty acids (VFA). Between 22 and 25 days of age, a highly significant drop in CP content was found, associated with an increase in NDF content. RNA values tended to decrease with age, but it is striking that the RNA/CP ratio suggests that about 50% of CP is microbial N, very early in the development (22 days). No significant changes of ammonia nitrogen concentration with age were observed, and lactic acid concentration showed some significant changes, suggestive of a decrease after weaning. Total VFA concentration is suggestive of a progressive and significant (P < 0.01) increase reaching a plateau after 42 days (83.7 mmoles/kg). Molar proportions of propionate and butyrate varied significantly (P < 0.001) and inversely with age. Propionate drops by nearly 50% while butyrate proportion doubles between 22 and 56 days of age. The shift from a propionic to a butyric pattern occurs already at day 25. Correlation analysis revealed significant associations between CP-NDF and RNA. The significant negative correlation between pH and daily weight gain reflects the relation caecal pH-animal health. PH was correlated with lactate and VFA concentration.

[EN] Caecal contents were collected from six 16h fasted (F) and six non fasted (NF) rabbits, sacrificed between 9 and 1 Oam. They were incubated for 24h/39ºC and net productions of volatile fatty acids (VFA) and methane were determined. In a separate preliminary experiment, caecal contents obtained from a F and a NF rabbit were incubated with starch, cellulose or pectins. In F animals, total VFA concentration was lower (P, [FR] Des contenus caecaux de six lapins él jeún (F) depuis 16h et six autres ayant re

The inverse form of recessive dystrophic epidermolysis bullosa is a rare genodermatosis characterized by a smouldering course of integumental blistering with improvement of lesions in adulthood, preferential localizations of lesions in flexural areas, severe oral and esophageal mucosal involvement and nail dystrophy. We describe a 41-year-old patient showing all the typical features of this form of epidermolysis bullosa. Ultrastructural findings in specimens obtained from perilesional and healthy skin were similar to those usually observed in the Hallopeau-Siemens form of epidermolysis bullosa. The patient has been treated with phenytoin for a period of 9 months with considerable improvement of the skin manifestations.

The trial was carried out to investigate the effects of adding to the diet of rabbits vitamin E (40; 300; 500 ppm) and C (0; 500 ppm), on vitamin E deposition in the muscles and organs, on the oxidative stability of muscular lipids, and on various meat quality characteristics. The α-tocopherol content in muscles and organs was roughly doubled by feeding the highest levels of vitamin E; it was also increased by giving 500 ppm of vitamin C, but only in those muscles of rabbits receiving 40 ppm of vitamin E. The α-tocopherol content in tissues was negatively correlated with TBARS values of the longissimus dorsi (LD) at days 6 and 8 post mortem (p.m.). Five hundred parts per million (ppm) of vitamin C increased lipid stability of the LD at both 6 and 8 days p.m., though its effect was significant only with 40 ppm of vitamin E. Moreover, 500 ppm of vitamin C resulted in the lowest L(*) and highest pH values at all p.m. times, when the dietary vitamin E was equal to 40 ppm, and in the highest L(*) and lowest pH values when the vitamin E was equal to 300 ppm. Conversely, weight losses of the LD were the lowest, at days 6 and 8 p.m., in the group fed the highest levels of both vitamins.

We present a very extensive family tree, who includes six generations and 17 women and 9 males affected by ectodermal Dysplasia. The clinical symptomatology is more serious in the males than in the females. In our family the syndrome manifests a segregation that suggests a semi-dominant X-linked heredity.

A sample of the Italian population was investigated to determine the CHE1*u, CHE1*a and CHE1*f allelic variants at the polymorphic locus CHE1 for the serum cholinesterase enzyme. We examined 4051 serum samples from schoolchildren of Milan and estimated the following allelic frequencies for the CHE1 locus: CHE1*u = 0.9636; CHE1*a = 0.0263; CHE1*f = 0.0101. These allelic frequencies are compared with those from other Italian, European, North African and Middle-Eastern countries. Our study confirms the validity of Garry's method in discriminating between the "usual" genotype and the "atypical" and "fluoride-resistant" ones.

In vivo CH4 production from four rumen-fistulated sheep fed fresh ryegrass-white clover (Lolium perenne – Trifolium repens) diets ad libitum was monitored using C2H6 as a tracer gas. Treatments comprised mixed pastures at two different fertilisation rates (0 vs. 150 kg N ha–1 yr–1) and at two periods in the growing season (early, June–July vs. late, August–September). Higher crude protein (CP) [22.5% dry matter (DM)] in late vs. early season (13% DM) was associated with increased importance of protein fermentation, as suggested by higher rumen concentrations of iso-acids [3.7 ± 1.0 vs. 2.4 ± 0.9% total volatile fatty acids (VFA)]. However, rumen CH4 production (25.8 ± 5.0 L kg–1 DMI) was not affected, probably because of compensatory seasonal changes in the chemical composition of the pasture, su0 as reduced water-soluble carbohydrates (WSC) (13.0 ± 2.6 vs. 4.9 ± 1.4% DM) or increased neutral detergent fibre (NDF) (48.5 ± 6.1 vs. 57.4 ± 4.6% DM). Although clover saponins might have a defaunation and CH4 inhibitory effect, considerable seasonal or fertiliser-induced changes in clover proportion did not affect rumen protozoal concentrations (8.8 ± 1.6 ×105 mL–1 rumen contents, early season), rumen methanogenesis or microbial growth as suggested from urinary excretion of purine derivatives (6.7 ± 1.7 mmol d–1). In contrast, however, a clear animal effect was found: on average, one animal produced less CH4 than the three others (20.3 vs. 27.6 L kg–1 DMI). Key words: Ryegrass, clover, N fertilisation, season, rumen, methane Mbanzamihigo, L., Fievez, V., da Costa Gomez, C., Piattoni, F., Carlier, L. et Demeyer, D. 2002. Les émissions

Le piante ornamentali esercitano un ruolo sempre più importante nella nostra vita legata ad una società tecnologica e sono diventate elementi indispensabili per migliorare la qualità dell’esistenza dell’uomo.

Hypogeous fungi are common in arid and semi-arid areas of the Mediterranean basin and, in particular, they are found in Italy, Spain, northern African countries (especially in Morocco, Algeria, and Tunisia), and in the Middle East. These fungi and, in particular, some species belonging to the genus Tuber and the desert truffles (Terfezia spp. and Tirmania spp.) form ascomata of considerable economic value. In this review, a panorama of hypogeous fungal diversity and information on their ecology in Mediterranean arid and semi-arid ecosystems have been reported; their economical importance and cultivation potential are also underlined.

Results of field trials using natural compounds to control Bremia lactucae, the downy mildew of lettuce, on two different cultivars (Trocadero and Iceberg) cultivated in two different periods (June and August-September), are reported. Tannino C, Sulfex, PS05_13, SAM_TSN and Xedafos resulted to be the best ones; also Agricolle and Micoplan provided better results than the traditional cupric, although to a lesser extent than the first group. In terms of increase in plant vigour, in both trials the best results were observed with Micoplan, Sulfex, Tannino C, PS05_13, PS06_13, S1, EM Bokashi 2/5 + EM5 and Xedatim.

Vengono riportati i risultati di una prova di campo con sostanze naturali, saggiate secondo tre diverse modalità d’impiego (solo concia del seme; concia del seme + trattamenti fogliari; solo trattamenti fogliari.) contro i patogeni fungini di frumento duro (cv. Latinur) e tenero (cv. Bologna). Tutti i prodotti hanno influenzato positivamente la vigoria vegetativa ma solo alcuni hanno manifestato un buon controllo della gravità e dell’incidenza delle malattie riscontrate (ruggini da Puccinia recondita e P. graminis) sul tenero. In particolare, si è evidenziato che alcuni prodotti esercitano un miglior controllo dell’incidenza della malattia se utilizzati come concianti; tra questi: Agricolle, Micosat F, Mycostop e Curex. Per quanto riguarda la gravità della malattia alcuni prodotti (Agricolle, Micosat F e Micoplan) hanno controllato l’insorgenza sia di ruggine bruna che nera. L’emergenza del duro è stata fortemente penalizzata dal particolare andamento climatico e inoltre sulle colture non si sono riscontrate malattie fungine.

Le recenti decisioni della commissione consultiva UE sulla limitazione dei fitofarmaci in agricoltura stanno costringendo gli stati europei ad un utilizzo sempre minore di sostanze chimiche di sintesi. Prove da noi condotte negli ultimi anni (Bianchi et al., 1997; Zechini D’Aulerio et al., 1998, 2002, 2004, 2008) hanno dimostrato buona azione antifungina di rameici a basso dosaggio e sostanze naturali di diversa origine, soprattutto contro le peronospore. Si è pertanto ritenuto di estendere la sperimentazione di tali prodotti contro Peronospora destructor su cipolla (cultivar ‘Tropea’) in un campo sperimentale situato a Selva di Imola (BO) e gestito da Astra Innovazione e Sviluppo. Sono stati confrontati prodotti rameici a basso dosaggio [solfato di rame tribasico complessato con peptidi ed aminoacidi (Peptiram TBCS); gluconato di rame 8% (Labicuper); ottanoato di rame 10%] ed altri di origine naturale o biologica [bicarbonato di potassio 85% (Armicarb 100); alginato 28% (Agricolle); un fertilizzante a base di P 26% e K 17% (Micoplan); un biostimolante contenente Al 1%, Fe 0,2%, Zn 0,2%, Mn 0,2% (Microsil 500); un biofungicida a base di Streptomyces griseoviridis (Mycostop)]. Si è utilizzato solfato di rame 20% (Poltiglia Bordolese Disperss) come testimone chimico. I trattamenti sono stati effettuati con pompa a spalla ogni 7 giorni, da metà giugno a fine agosto 2009. I sintomi della malattia sono stati quantificati secondo una scala di gravità con classi percentuali di superficie fogliare colpita. Materiale vegetale infetto è stato campionato per l’identificazione, al microscopio ottico, del patogeno coinvolto, che è risultato essere P. destructor. I risultati finali hanno evidenziato minore presenza di malattia nelle tesi trattate con poltiglia bordolese Disperss (22,2%), Microsil 500 (30,2%), Peptiram TBCS (30,5%), Armicarb 100 (31,1%) e Labicuper (33,3%), rispetto al 67,9% delle parcelle testimoni. Risulta, quindi, confermata l’efficacia di rameici complessati e di alcune sostanze naturali anche nella lotta contro la peronospora della cipolla.

In Italy Fusarium oxysporum f.sp. melonis induces an important disease of muskmelon. Four races of this pathogen are currently known, i.e. 0, 1, 2 and 1-2. Varietal resistance of the only reliable approach for preventing wilt induced by race 0, 1 and 2, which were studied in this work. Investigations carried out between 2008 and 2010 aimed first at verifying the resistance of the cultivars certified as "resistant" by seed companies. To this aim, 3 "resistant" cultivars (Bingo, Giusto and Sweetness) were compared with three susceptible ones (Cantalupo, Harper and Retato degli Ortolani), by infection plants with each of the three pathogenic races (spore suspension: 106 conidia/ml). Among the resistant cultivars, one resulted totally resistant (Bingo) whereas Giusto and Sweetness showed a partial resistance (disease severity: 10%). Similar differences were observed among the susceptible cultivars for disease severity which was close to 100% in Retato whereas for Cantalupo and Harper it ranged between 80 and 85%. Differences in pathogenicity were also observed among the pathogenic races tested: race 0 and 2 caused the highest disease severity in Bingo and Retato. Attempts were made to investigate the mechanisms involved in plant resistance. We found that root exudates did not affect neither conidia germination rate nor mycelial growth. Currently, studies on the development of promycelium are carried out. Further investigations will aim at highlighting possible differences between resistant and susceptible cultivars in post infection root morphological modifications, by means of fluorescence and microscopy techniques.