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El objetivo de este estudio fue determinar la composición química, la energía bruta, la digestibilidad de la materia orgánica (DMO), el valor nutritivo y el contenido de amino ácidos del lupino blanco (Lupinus albus L.) durante su ciclo de crecimiento. Las muestras de plantas se recolectaron cuatro veces en etapas morfológicas progresivas desde la etapa de yema tardía hasta la de vaina verde joven. Se realizaron dos réplicas en cada etapa y todos los datos fueron valores medios de los análisis triplicados realizados para cada muestra. La variabilidad en las características de la calidad de las muestras se analizó para su significación estadística mediante el análisis de varianza para comprobar el efecto de la etapa de crecimiento. La materia seca (MS) y las fracciones fibrosas se incrementaron durante la maduración. No se encontraron diferencias significativas en la materia orgánica (MO), la ceniza y el extracto etéreo. La energía bruta osciló entre 17.3 y 17.7 MJ/kg de MS, mientras que la proteína bruta, la DMO y la energía neta para la lactación disminuyeron con el avance de la maduración desde 140 hasta 130 g/kg MS, desde 693 hasta 615 g/kg MO y desde 5.5 hasta 4.9 MJ/kg MS, respectivamente. Las proporciones relativas de los aminoácidos (AA) individuales y totales no fueron afectadas por la fecha de cosecha. Los ácidos aspártico y glutámico fueron los AA más abundantes en la planta durante el crecimiento. El lupino blanco cosechado en la etapa de florecimiento suministra forraje de buena calidad para los rumiantes y puede ayudar a mejorar la autosuficiencia de las granjas en términos de forrajes proteicos domésticos. Se necesitan más estudios para determinar el rendimiento de MS de este cultivo y el consumo de este forraje por los rumiantes.

The chia was grown in the Po valley, northern Italy. The chia growth was characterised by a rapid dry matter (DM) accumulation in the herbage during development and the DM content increased from 84 to 224 g/kg fresh matter (FM). Significant differences were observed in the pH, that range from 6.0 to 6.2. The water soluble carbohydrates (WSC) content increased from 86 to 213 g/kg DM, while the buffering capacity (BC) decreased from 689 to 416 meq/kg DM with increasing growth stage. The soluble nitrogen (SN) ranged from 105 to 174 g/kg TN. Four types of silage were prepared with no additives (cut silage and wilted silages at three levels of wilting) at budding stage to investigate the effects of wilting on the chemical composition and fermentation characteristics of the silage. The results of ensiling indicate that the fermentation of chia is characterized by the presence of some alcohols and volatile fatty acids and a lack of lactic acid. The variability in the herbage quality characteristics harvested at five different stages of maturity and the variability in the silage characteristics were analysed for their statistical significance via analysis of variance (ANOVA) to test the effect of the growth stage and wilting level, respectively. No significant differences were found in TN, gross energy, pH or the fermentation characteristics, with the exception of isobutyric acid, which decreased with increasing wilting level. The good results obtained in lab-scale silos, with silage characterised by a restricted fermentation and a lack of butyric acid at the three high wilting levels, would seem to suggest that chia has the potential for large scale ensiling, if it is harvested at budding stage and wilted to a DM level of more than 285 g/kg FM. Further research is required to define the conservation quality in farm scale silos or in lab silos with additives that improve silage fermentation when chia is ensiled at cut or at low wilting levels.

This study was set up to evaluate the effect of the inclusion of Curcuma longa (CL, 3 g kg-1) in rabbit diets on the apparent digestibility of mixed feeds with 40 g kg-1 palm oil (PO) and 4 g kg-1 corn oil (CO). Forty weaned nine week old crossbred rabbits were randomly assigned to four groups of 10. The animals were housed individually under standard conditions. Four isoproteic and isoenergetic diets were formulated with CO, CO+CL, PO, and PO+CL. After 1 week for adaptation to the diets and cages, the animals were fed ad libitum for 24 days. The apparent digestibilities of the four diets were determined in the last week. The faeces were collected over a period of five days using a nylon net placed under the cages of each trial, to avoid urine contamination. The dietary and faecal samples were analysed to determine dry matter, crude protein, ash, ether extract, neutral detergent fibre, acid detergent fibre, gross energy and acid insoluble ash (AIA). The digestibility coefficients were calculated according to the indirect digestibility method using AIA as an inert marker. The analysis of variance was used to evaluate the effects on the digestibility of the four different rabbit diets. The means were compared with a Duncan test and the significance level was set at P

Scopo di questo lavoro è stato quello di determinare il valore nutritivo di orzo trattato tecnologicamente per migliorarne l'assimilabilità da parte del cavallo. Sono state pertanto effettuate sei prove di digeribilità, di cui tre realizzate nel 2004 con razioni costituite da solo fieno, da fieno più orzo schiacciato e da fieno più orzo fioccato e tre svolte nel 2005 con razioni costituite una da solo fieno e due da fieno più orzo fioccato di due differenti ditte. Il periodo sperimentale di ciascuna prova è stato di 6 giorni, preceduto da un periodo di adattamento di 14 giorni. La digeribilità apparente di sostanza secca, sostanza organica, energia grezza, proteina grezza, fibra resistente al detergente neutro (NDF) e fibra resistente al detergente acido (ADF) è stata determinata attraverso il metodo delle ingesta/excreta utilizzando una sacca con imbracatura (horse diaper) per la raccolta totale delle feci. La digeribilità apparente dell'orzo è stata calcolata a partire dalle digeribilità dei due fieni e delle quattro razioni impiegate. I risultati mostrano che l'impiego di orzo tecnologicamente trattato migliora la digeribilità della razione rispetto ad una dieta a base di solo fieno di prato stabile al primo taglio ed in particolare la fioccatura aumenta la digeribilità dell'orzo rispetto alla semplice schiacciatura. Esistono tuttavia sensibili differenze nella digeribilità dei tre orzi fioccati esaminati, dovute probabilmente alle diverse condizioni, in particolare di temperatura, impiegate nel processo di fioccatura.

The objective of this study was to determine the effects of the inclusion of dehydroepiandrosterone (DHEA) and Spirulina platensis (SP) in low fat (LF) and high fat (HF) diets on the morpho-biometrical parameters, apparent digestibility and longissimus dorsi (LD) muscle composition of New Zealand White rabbits. The trial was carried out on 24 rabbits that were randomly allocated to six groups of four animals each, kept in individual cages. The three LF diets and the three HF diets (control, with 0.02% DHEA and with 1% SP, respectively) differed on the basis of the level of fat (3% and 13%, respectively). The experimental period lasted 3 months and the faeces were collected during the last week. The measured parameters were the initial and final weight, waist circumference and length, digestibility of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), and gross energy (GE). At the end of the experimental period, the rabbits from each group were slaughtered without fasting and the longissimus dorsi (LD) muscles were collected to the determine chemical composition and GE. The results show that the DHEA supplementation in rabbits fed high fat diets decreases EE digestibility, while the SP supplementation increases CP digestibility of low and high fat diets. The DM, OM, and GE digestibilities, morpho-biometrical parameters and meat composition were not significantly affected by the type of antioxidant, in either the rabbits fed low fat diets or in the rabbits fed high fat diets.

Saffiower (Carthamus tinctorius L.), which is grown as a high-quality forage crop for dairy cattle and dairy sheep in Mediterranean conditions, has been studied to determine the chemical composition, in vitro organi c matter digestibility (IVOMD), gross energy (GE) and fatty acid (FA) profile ofthe plant during growth. Herbage samples were collected five times at progressive morphological stages rrom the late vegetative to the early flower stage. The dry matter, organic matter, fibrous rractions and GE content increased with increasing growth stage, while the ash, crude protein and IVOMD decreased during growth. Linoleic and a-linolenic acid were the two main FAs in the saffiower plant during the growth cycle and theyranged rrom 158 to 188 glkg and 521 to 586 glkg ofthe total FA, respectively. The quality and IVOMD of saffiower, like other forages, depends on the development ofthe plant and decreases with increased maturity. A forage with a good nutritive value can be obtained by harvesting saffiower at the early flowering stage.

Galega (Galega officinalis L.) is one of the least investigated perennial leguminous herbs. It is usually present in natural pastures, grazed by animals, in Mediterranean areas and in the Italian Alps and Apennines below 1000 m. The aim of this study was to investigate the effect of the stage of maturity on the ensilability characteristics and to evaluate the fermentation quality of silage produced from first cut and regrowth of G. officinalis in the Po valley, northern Italy. The growth of G. officinalis was characterised by a rapid Dry Matter (DM) accumulation in the herbage during development and the DM content increased from 111-157 g kgG1 Fresh Matter (FM), while at the regrowth stage it was 180 g kgG1 FM. No significant changes were observed in the pH or Water Soluble Carbohydrates (WSC) content. The Buffering Capacity (BC) was lower at the regrowth than at the other three first cut stages, while Total Nitrogen (TN) and Soluble Nitrogen (SN) were low at the budding stage. Three types of silage without additives, wilted silage 1 day after wilting at the budding stage, wilted silage 2 days after wilting at the budding stage and wilted silage 1 day after wilting at the regrowth stage were prepared to investigate the effects of wilting on the chemical composition and characterstics of silage fermentation. The results of ensiling indicate that the fermentation of pure G. officinalis is characterized by the presence of alcohol and acetic acid and a lack of lactic acid and butyric acid. The good results obtained in lab-scale silos would seem to suggest that G. officinalis has the potential for large scale ensiling, if galega is harvested at the budding stage or during regrowth and then wilted to a DM level of >350 g kgG1 FM.

The aim of the present study was to examine the effects of Dehydroepiandrosterone (DHEA) on the perirenal fat and Longissimus Dorsi (LD) muscle Fatty Acid (FA) profile of rabbits fed diets with low (3%) and high fat (13%) contents. DHEA was given in the diet (0-0.02%) to 15-week-old male New Zealand White rabbits for 3 months. At the end of the experimental period, the rabbits from each group were slaughtered without fasting and the perirenal fat and LD muscle were collected to determine the FA profile. The results show that DHEA, at the experimental dosage, does not influence the FA profile of perirenal fat or LD muscle of rabbits fed different fat content diets.

È stato valutato lo stato di conservazione di mangimi per conigli con 0%, 8% e 16% di semi di lino. I tre mangimi sono stati esposti all'aria o ad aria + luce per verificare l'andamento dello stato di conservazione. A distanza di 31 e 64 giorni di conservazione sono stati valutati: il numero di perossidi ed il potere antiossidante. L'impatto dell'esposizione ad aria + luce durante il periodo di conservazione del mangime è risultato notevolmente superiore rispetto alla sola esposizione all'aria. I mangimi esposti all' aria e alla luce infatti hanno sviluppato un elevato numero di perossidi raggiungendo un picco al 31° giorno di conservazione. L'attività antiossidante dei mangimi è risultata bassa e non in grado di contrastare il processo di irrancidimento.

A properly running gut is a key point for the welfare of the horse. In particular the use of prebiotics and probiotics for the modulation of the large intestine fermentations is very important in many field situations. Structural carbohydrates such as cellulose and hemicelluloses cannot be digested by the horses digestive enzymes, but can be fermented by fermentative micro organisms in the large intestine, thus providing volatile fatty acids (VFA) that are used as a fuel source by the horse. The use of prebiotics and probiotics association increases the beneficial effects of these compounds in the gut, thus obtaining a symbiotic effect: in this way there is an increase of the fermentative microorganisms survival with an important positive effect on the fermentations. The main objective of this study was to evaluate the effect of a new symbiotic supplement, containing prebiotics, probiotics, L-glutamine and herbal extracts, on the digestibility of a poor quality hay, typical feeding basis of Italian stables. The supplement we tested, fed at a 48 g/horse/day level to horses fed hay only, increased the apparent digestibility of dry matter, organic matter, energy and fiber fractions (NDF and ADF).

The objective of this study was to determine the effects of different levels of golden flax (Linus usitatissimum L.) seeds (GFS) on rabbit performance and nutrient utilisation. The trial was carried out on 30 crossbred rabbits that were randomly allocated to 3 groups each with 10 animals (5 male and 5 female rabbits each), kept separate in individual cages. Three diets were formulated with increasing levels (0, 8, or 16%) of GFS. The experimental period lasted 5 weeks and the faeces were collected during the last week. No obvious health problems were encountered during the experiment. The measured parameters were growth performances and digestibility of Dry Matter (DM), Organic Matter (OM), Crude Protein (CP), Crude Fibre (CF), Ether Extract (EE), Nitrogen Free Extract (NFE), Neutral Detergent Fibre (NDF), Acid Detergent Fibre (ADF) and Gross Energy (GE). The weight gain and food intake did not differ significantly (p>0.05) among the dietary treatments. The digestibility coefficients were calculated according to standard procedures following the indirect digestibility method, using acid insoluble ash as an inert marker. The apparent digestibility of the mixed feed with a GFS inclusion level of 16% was higher than those of the other 2 diets. It can be concluded that golden flaxseed can be given to rabbits at levels of up to 16% in the diet without any adverse effects on growth performance and with a better digestibility than the control diet.

BAKGROUND: The quality of forages changes according to the morphological stage and it is important to define the nutritive characteristics and fatty acid (FA) content of the crop during growth. That allows a choice of cutting time in order to optimise the uilisation of the forages and to identify new sources of polyunsatured fatty acids (PUFAs) for ruminants. Our aim was to study changes in the chemical composition, in vitro organic matter digestibility, gross energy, and FA content, of linseed (Linum usitatissimum L.) samples collected from the stem extension to the mature seed stage. RESULTS: The development of linseed quality during growth is characterised by a progressive increase in the fibrous fractions and a decrease in crude protein, ether extract, ash, and in vitro organic matter digestibility (IVOMD). The FA profiles in the plant were characterised by four dominant FAs: palmitic acid (PA, 16:0), stearic acid (SA, 18:0), linoleic acid (LA, 18:2n-6) and ±-linolenic acid (ALA, 18:3n-3). PA, SA and LA increased from the visible bud stage to mature seed stage, while ALA decreased, consequently the n-6/n-3 polyunsaturated FA ratio of the plant increased during growth. CONCLUSION: The chemical composition and FA profile of linseed is closely connected to the development of the plant. Forage with a good nutritive value and with a content of unsaturated FA that is suitable for herbivorous feeding is still obtained by harvesting green linseed at the brown capsule stage.

Near infrared (NIR) spectroscopy methods are now widely used in animal science to predict the chemical composition of forages and other foods, including silage. NIR is a convenient and rapid alternative to chemistry methods, which are expensive and time consuming. However, silage analysis using NIR has so far been limited to oven-dried samples, because volatile compounds are lost during the drying process. The development of NIR techniques for fresh silage would improve efficiency by eliminating the drying and grinding processes and would prevent volatile losses. The aim of this study was to examine the feasibility of predicting fermentation characteristics in fresh silage using an NIR spectrometer or an electronic nose. Silage samples were taken from 19 Italian stock farms and were analysed for dry matter (DM), pH, buffering capacity (BC), total N, soluble N, ammonia N, alcohols, lactic acid and volatile fatty acids (VFA). The wide range of variation observed in the conservation quality seemed adequate to cover a wide variation in Italian farm silages. NIR analyses of the 33 silage samples were carried out with a Lab-SPEC PRO (ASD) in a 350-2500 nm spectral range......

Purslane is an excellent source of omega-3 fatty acids, amino acids, and vitamins. The aim of this research was to study the effect of different nitrogen levels and NO3--N/NH4+-N ratios in the nutrient solution on the yield and on the oxalic acid content and fatty acid profile in purslane grown in a soilless culture system. Two experiments were carried out to test different levels of nitrogen: 1) 8-12-16 mmol L-1; 2) 0-12-24-36 mmol L-1. A third experiment was carried out maintaining the N level fixed (12 mmol L-1) but varying the NO3--N/NH4+-N ratio: 60/40, 40/60, 0/100. The results indicated that plants grew increasing nitrogen level up to 36 mmol L-1. Nitrogen supplied in both forms NO3- and NH4+ produced bigger plants compared to N supplied in NH4+ form only. Nitrogen did not significantly influence the polyunsaturated fatty acid content in the canopy. Significant trends were found for a-linolenic acid (LNA; 18:3 n-3) and linoleic acid (LA; 18:2 n-6) indicating a favourable accumulation of omega-3 fatty acid with increasing N; palmitic acid decreased by increasing N and by switching NO3-/NH4+ ratio toward NH4+ level in the nutrient solution, but using 0/100 NO3-/NH4+ decreased plant quality. Increasing N lowered oxalic acid production and palmitic acid content enhancing purslane nutritional quality. Keeping high N level in the nutrient solution with a 40/60 NO3-/NH4+ ratio would give the best results in terms of yield, oxalic acid concentration and fatty acid profile.

The digestibility of horse feeds and rations can be determined using different techniques such as calculations based on the chemical composition, in vivo or in vitro methods. The marker methods overcome difficulties like discomfort for the animals and longer experimental times encountered using the ingesta/egesta method. In field conditions, a natural indigestible marker like acid-insoluble ash (AIA), with no changes in the normal ration, could be a very useful tool for digestibility trials. A group of six standardbred horses was used in a set of seven apparent digestibility trials. The diets were based on a first-cut meadow hay added to three different cereals (barley for trials 1 and 2; oats for trials 3 and 5 and corn for trials 6 and 7), the hay : concentrate ratio being 60 : 40 or 70 : 30 on a dry matter basis. Feedstuffs and faeces were analysed to determine the AIA content, using 2N HCl or 4N HCl technique. No differences about AIA concentration were found between the two methods for means and accuracy in each diet. Digestion coefficients for each diet did not differ with AIA method, even if in some trials interfering factors consistently lowered the overall values. Consequently, the AIA 2N HCl can be considered the easier and cheaper method to state apparent digestibility in field conditions, and a good tool for digestibility trials in horses fed hay-based diets.

The aim of this research was to study the effect of different nitrogen levels and nitrate/ammonia ratio on the yield and the oxalic acid content and fatty acid profile in purslan grown in soilless culture system.

The apparent digestibilities of hay or hay plus concentrate (60:40) rich in by-products including soja hulls were determined by means of two in vivo digestibility trials, each performed on 6 saddle horses weighting about 506 kg and 503 kg, respectively, over a 6 day faeces total collection period with a previous 14 day adaptation period. The diets were based on first cut meadow hay, whose digestibility was estimated in the first trial, and on the same hay with a mixed feed in the second trials at a feeding level close to maintenance. The apparent digestibility of the dry matter, organic matter, gross energy, crude protein, NDF and ADF were measured by the ingesta/excreta procedure using a suitable device. The apparent digestibility of the concentrate was calculated from the above data. The data from two of the six horses resulted aberrant and, consequently, the paper refers to the results coming from four horses only. The results showed that the addition of the mixed feed to the hay improves the digestibility of the ration only for the crude protein, while the digestibilities of NDF and ADF were lower than those of hay alone and digestibilities of dry matter, organic matter and gross energy were steady. These results could mainly be ascribed to a negative effect of some by-products on the microflora activity in the large intestine.

The aim of this work was to evaluate the urinary and faecal losses in horses fed three diets differing for forage/concentrate ratio (diet 1:100 % hay, diet 2: 75% hay + 25% of a mixed feed, diet 3: 50% hay + 50% of the same mixed feed) at a feeding level close to maintenance. The trials were performed on 4 saddle horses weighting about 550 kg, over a 6 day faeces and urines total collection period after a previous 14 day adaptation period. A horse diaper was utilised for the fecal and urine collection. Food consumption was recorded daily. Before analysis, the faecal and urinal samples were freeze-dried and ground. Analyses on all samples for dry matter and N were carried out according to the standard methods of Association of Official Analytical Chemists 1990 . The gross energy was determined with an adiabatic calorimeter bomb (IKA C7000, Staufen, Germany). The percentages of nitrogen retention and nitrogen digestibility, the metabolisable energy (ME) and digestible energy (DE) percentages on gross energy were measured by the ingesta/excreta procedure and by taking into account the urinary losses for all the rations. The nitrogen digestibility and retention increased (P < 0.01) with increasing amounts of the mixed feed in the ration; the same trend, even if not significant, was found for the metabolizable energy and digestibility of gross energy percentages. The urine energy was very low. The digestible crude protein of the diet 1 (100 % hay) determined by difference between nitrogen intake and nitrogen in the faeces was compared with the data obtained with the regression equations formulated by Martin-Rosset (1994), the result were found to be similar. The digestibility of energy of the diet 1, determined from digestibility of organic matter by the equations and the ME/DE ratio was also near to the one measured in the trial.

In Molise Region (Italy) wild horses named "Pentro horses" (autochthonous population) are still bred. The breeding area is a natural pasture. It is 2200 ha extended including a broad plane surrounded by wooden hills. This paper is part of a research project concerning the study of the nutritional characteristics of all the area over a two years period. The aim is to improve the management of the herd and to define the stocking rate in order to prevent the risk of extinction of the equine population without compromise botanical features of the area. This paper shows the variation of the chemical composition of the grass during the grazing period (May to October) over two following years. The forage samples were collected from 5 experimental areas that represent the prevalent land typology (2 for the pasture system and 3 for grazing meadow system) according with the Corral and Fenlon method (1978). Dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL) and gross energy (GE) were determined. Data were analyzed with a one-way ANOVA test using month and area as factors. The results show that seasonal and yearly climatic variations significantly affect chemical composition of the pasture. In particular, the most influenced parameters are DM, CP, ADF and to a less extent NDF, while OM, ADL and GE show smaller differences during the observed period. The differences among the areas have to be ascribed to the different botanical composition and to the different draining capacity of the soil and also in this case the greatest variations are for DM, CP and ADF. Since these parameters are those that more influence the nutritive value of the pasture, it seems possible that during the most critical months (July-September) the requirements of the herds could be unsatisfied. For this reason, in that period a different management of the herd (hay integration, pasture rotation) should be examined to avoid pasture and soil degradation.

A data set of 551 samples of grass and legume harvested at different locations and at different stages of maturity were examined to develop and evaluate some prediction equations for the gross energy of Mediterranean forages. The sample set covered a broad range of forage species including 339 samples of lucerne (Medicago sativa), 103 samples of Italian ryegrass (Lolium multiflorum Lam.), 72 samples of sulla (Hedysarum coronarium L.), 27 samples of sainfoin (Onobrychis viciifolia Scop.), and 10 samples of red clover (Trifolium pratense). These samples were collected and analysed for crude protein (CPo) and gross energy (GEo), expressed per kg of organic matter (OM) in order to eliminate the influence of the ash contents. Of all the regression equations derived from the data for the prediction of GEo, the following one in particular gives a good prediction: GEo (kcal/kg OM) = 4354 + 2.131 CPo ± 14 (r = 0.81; n = 551). Its use represents an immediate system for predicting the energy content of Mediterranean forages and it is a valid alternative to the direct determination using an adiabatic bomb calorimeter.

Aim of the research was to test the effect of different housing systems, organic and intensive, on meat quality of a rabbit local breed/population of Tuscany, characterized by low growing. 60 rabbits of this local rabbits breed/populations were housed in colony cages, at open air (Group A) under organic system, according to an official organism of certification which states the esclusive use of local strains; 60 rabbits of the same local breed/populations (Group B) and 60 hybrids (Group C) were housed in colony cages under conventional system. The rabbits were ad libitum fed with an organic diet (alfa-alfa hay and pellet). At the same live weight (2400 g) but at different ages (local population: 102 days; hybrids: 90 days) 30 animals of each group were slaughtered. For each group samples of Longissimus Dorsi (LD) were taken to evaluate pH, colour, Water Holding Capacity (WHC) (n=25), nutritional value, fatty acids composition and lipid oxidation (n=4). Meat of animals belonging to Group A (local genotype, reared under organic system), showed different physical meat properties compared with the other groups. In Group A the lowest muscular acidification and the highest value of WHC were found (pHu=5.79 vs 5.59 and 5,63, WHC: 52.3 vs 47.8 and 47.9, for Group A, B and C, respectively, P

The use of a diet based on silages or haylages is becoming increasingly more important in the prevention and control of some pathologies that affect the breathing apparatus of horses. The present knowledge concerning conservation quality and the nutritive value of some of the most commonly used grass silages is studied in depth in this work. In order to evaluate the conservation quality of silages, a series of determinations is necessary that ranges from the dry matter to the chemical composition, from the gross energy to the pH and to the dosage of the fermentation products (lactic and butyric acid, ammonia, etc). The nutritive value of silages is often better than that of the corresponding hays due to the earlier stage of the grass at harvesting and to the minor loss of leaves, in particular for legumes. The use of silages could therefore be a valid alternative to hay, on condition that these products are well conserved, have kept a nutritive value that is similar to that of the original grass, are without risks for the health of the horses (listeriosis, botulism and aflatoxin) and are available in different sizes according to the requirements of the stables. In conclusion, grass silages have proven to be useful for feedstuff for horses, in function of their quality and of the working procedures that their use would imply for the stables. An analytical evaluation of the quality of the product, before their use, is essential for a correct insertion in the rations and to prevent the most important intestinal problems that affect horses.

BACKGROUND. Italian ryegrass (Lolium multiflorum Lam.) is a high yielding crop, that is widely grown in Italy as a winter crop preceding maize for silage in the same year, and is well suited for soil conservation and prevention of groundwater pollution. This research studied the effect of weather conditions, plant maturity, ploidy, and rate of application of fertilizer N on the variation in dry-matter (DM) content, water-soluble carbohydrates (WSC), buffering capacity (BC), crude protein (CP) and nitrate content of Italian ryegrass grown in winter and spring as a double crop with maize METHODS. The research was conducted between 1991 and 1996 in the Po Valley, Italy. A data set of 160 observations was available for regression analyses. A multiple regression analysis was used to correlate the DM content, WSC, BC, CP, and nitrate content to the weather and crop variables. RESULTS. The DM content was inversely related to the nitrogen application. It was high in the very early stages of crop maturity, decreased quickly to reach a minimum around the middle period of stem elongation and then increased with increasing maturity, varying from 101 to 326 g kg-1 fresh matter. The diploid cultivars resulted to have a DM content of 22 g kg-1 FM higher than the tetraploid over the whole growth cycle. The WSC content showed a great variability, ranging from 94 to 474 g kg-1 DM. The factors that negatively affected the WSC content were higher night temperatures in the three days before harvesting, the rate of application of N fertilizer applied in spring, and the advancing stage of development. The BC was observed to have a high variability with no significant relationship to the measured climatic and plant variables. CONCLUSIONS. For ensiling purposes, it is necessary to select diploid cultivars and to take particular care of application of fertilizer as a N top dressing especially when a large amount of organic N is applied to the preceding maize crop in order to avoid herbage with too low DM and WSC contents at cutting.

CommercialIy mixed feeds for light horse feeding are being used ' more and more and, in recent times, a particular role has been played by mixed feeds characterized by high fibre percentages together with pre-biotic or pro-biotic supplements. Consequently, more data about these new feeds is required. The apparent digestibility of two commercialIy mixed feed was determined by means of four in vivo digestibility trials (hay n.l; hay n. l + mixed feed n.l; hay n.2; hay n.2 + mixed feed n.2) each performed on 4 or 5 saddle horses weighting about 550 and 535 kg respectively over a 6 day faeces total colIection period with a previous 14 day adaptation periodo The diets were based on first cut meadow hay and two mixed feed at a feeding level close to maintenance. The two mixed feed were rich respectively in by-product of citrus fruits industry (citrus pulp) and in by-product of apple fruits industry (apple pectin pulp). The forage to concentrate ratios were 100:0 and 50:50, respectively, in the four trials. The apparent digestibility of the dry matter, organic matter, gross energy, crude protein, NDF, ADF and crude fibre were measured by the ingesta/excreta procedure for alI the rations and the hays. The apparent digestibility of the two concentrates were calculated from the above data. The results showed that the addition of the first mixed feed to the hay improves lightly the digestibility ofthe ration with the exception offibre fractions (crude fibre, NDF, ADF) that was lower; in the case ofthe second by-product the comparison with the digestibility values obtained with the hay only showed lower values for dry matter, organic matter, energy and NDF and negative values for crude fibre and ADF. These results could mainly be ascribed to a negative effect of these by-products on the microtlora activity in the large intestine, mainly of the cellulosolytic one. Nevertheless, it could be supposed the addition of preservati ve substances to the fibrous part of the raw materials that could negatively intluence the fermentation activity.

In the aim to validate the NIRS technique for rapid characterisation of mountain cheeses made at "Stazione Sperimentale Alpina" (Sauze d'Oulx) during three trials [A=2002: compared winter feeding (Hay) vs. easter feeding (Grass); B=2003: winter feeding with hay vs. grass-silage); C=2004: as B] as compared with their fatty acid (FA) composition, thirty-nine cheeses (Toma Piemontese and Reblochon) were scanned by a PE FT-NIR IdentiCheck spectrometer. The trial C validated the previous NIRS equations with better results than cross-validation of A+B dataset: on av.ge 1-VR was 0.32 and resulted improved in FA>10% (from 0,07 to 0,32), then in FA 2?10% (from 0,18 to 0,27) and as expected in the low class FA

The use of a diet based on silages or haylages is becoming increasingly more important in the prevention and control of some pathologies that affect the breathing apparatus of horses. The present knowledge concerning conservation quality and the nutritive value of some of the most commonly used grass silages is studied in depth in this work. In order to evaluate the conservation quality of silages, a series of determinations is necessary that ranges from the dry matter to the chemical composition, from the gross energy to the pH and to the dosage of the fermentation products (lactic and butyric acid, ammonia, etc). The nutritive value of silages is often better than that of the corresponding hays due to the earlier stage of the grass at harvesting and to the minor loss of leaves, in particular for legumes. The use of silages could therefore be a valid alternative to hay, on condition that these products are well conserved, have kept a nutritive value that is similar to that of the original grass, are without risks for the health of the horses (listeriosis, botulism and aflatoxin) and are available in different sizes according to the requirements of the stables. In conclusion, grass silages have proven to be useful for feedstuff for horses, in function of their quality and of the working procedures that their use would imply for the stables. An analytical evaluation of the quality of the product, before their use, is essential for a correct insertion in the rations and to prevent the most important intestinal problems that affect horses.

The aim of this work was to comparatively assess, by performing three "in vivo" digestibility trials differing for forage / concentrate ratio, the usefulness of the two methods of total collection of faeces and acid insoluble ash (AIA) in the determination of the apparent digestibility coefficients. Dry matter, organic matter, energy and crude protein apparent digestibility were studied for concentrate. The differences between the apparent digestibility coefficients were found to be influenced by - and to increase with - the percentage of concentrate in the diet. Regression equations with good correlation coefficients, based on the AIA method, were proposed for the extrapolation of the apparent digestibility coefficients of the concentrate alone.

Un sistema foraggero basato sull'insilamento dell'erba sfalciata in stadi precoci permette di ottenere foraggi di più alto valore nutrizionale e dietetico in confronto al tradizionale sistema di conservazione mediante fienagione. La produzione di foraggi di più elevata qualità nutrizionale, senza complicare troppo i cantieri di lavoro e il livello di meccanizzazione aziendale, può rappresentare un grande vantaggio per l'economia dell'azienda zootecnica montana poiché permette di abbassare i costi di produzione, riducendo l'uso dei concentrati acquistati. La formazione delle scorte invernali con foraggi locali di elevata qualità permetterebbe inoltre di produrre formaggi anche durante il periodo invernale, di legare maggiormente il prodotto caseario al suo luogo di origine e, nel caso di allevamenti biologici, semplificherebbe in maniera sostanziale i problemi di reperimento di alimenti certificati, che come tali sono caratterizzati da prezzi molto elevati. Lo scopo di questo lavoro è stato quello di valutare, in una situazione aziendale a 1800 m di quota, le ricadute applicative sul sistema foraggero e sull'intera filiera lattiero-casearia, determinate dall'anticipo dell'epoca di esecuzione del primo taglio del prato permanente, dalla conservazione dell'erba mediante insilamento in rotoballe fasciate e dal suo utilizzo nella razione delle vacche da latte. La ricerca ha inoltre valutato, mediante la caseificazione separata di partite di latte ottenute da vacche alimentate con razioni a base di fieno o di insilato, le caratteristiche qualitative e organolettiche dei formaggi prodotti e l'insorgenza di problemi durante la caseificazione e la stagionatura degli stessi. Per quanto riguarda la filiera lattiero-casearia, si è ottenuta la caratterizzazione dei foraggi sia dal punto di vista del contenuto in acidi grassi sia della componente volatile che presiede al cosiddetto "aroma" dei formaggi. L'importanza di ottenere un foraggio finito di qualità rappresenta, soprattutto negli allevamenti montani, un elemento chiave nella gestione dell'azienda. Infatti avere a disposizione foraggi di elevata qualità può ridurre significativamente la quantità di concentrato da somministrare agli animali con un conseguente risparmio economico mantenendo un più stretto legame con il territorio. La prova sull'andamento della produzione e della qualità dei prati permanenti ha permesso di evidenziare la possibilità di ottenere foraggi altamente qualitativi anticipando il taglio di 20-30 giorni rispetto alla data tradizionale di fienagione. L'adozione dell'insilamento in sostituzione della fienagione permette inoltre di ridurre i tempi di permanenza in campo e i rischi legati all'andamento meteorologico. Dalle prove di alimentazione effettuate nei due anni si è evidenziata la possibilità di introdurre con successo l'insilato nella razione delle bovine durante il periodo invernale, in quanto le caratteristiche chimiche e microbiologiche del latte non si sono discostate da quelle di animali alimentati con il fieno. Inoltre i formaggi prodotti non hanno evidenziato segni di fermentazioni anomale nei mesi successivi di conservazione e maturazione. È importante comunque sottolineare che i lievi aumenti nelle cariche di spore clostridiche nel latte prodotto con insilati, richiede comunque una maggiore attenzione nella cura dell'igiene in tutte le fasi dalla mungitura in poi, soprattutto nel caso in cui si operino caseificazioni di formaggi a pasta dura conservati per più di 6 mesi. Infine si è evidenziato chiaramente che l'introduzione del fieno-silo nella filiera aziendale ha ricadute positive sull'economia aziendale solo quando venga abbinato a un deciso anticipo dell'epoca di taglio, come evidenziato nella prova del secondo anno di sperimentazione. Infatti oltre al risparmio di 1 kg di concentrato/capo/d gli animali hanno mantenuto, o addirittura aumentato, la produzione media giornaliera di latte rispetto agli animali alimentati con razione a base di fieno.

La ricerca in collaborazione con il Dipartimento Agroselviter dell'Università di Torino, l'Associazione Regionale Produttori Latte Piemonte e l'Istituto Superiore Lattiero Caseario di Mantova, si propone di migliorare la stabilità aerobica degli insilati di mais su scala aziendale studiando e definendo le modalità attuative delle diverse fasi di preparazione e utilizzazione degli insilati. Per lo studio dei vari aspetti interferenti sulla riuscita degli insilati verranno valutati, oltre che la qualità degli stessi, la qualità del latte e le ripercussioni sulla caseificazione e sulla stagionatura delle partite ottenute in alcune situazioni tecnologiche. Lo studio si attuerà attraverso due linee, una di indagine su numerose aziende per mantenere l'aderenza della ricerca alla realtà operativa locale, e una di carattere sperimentale volta ad approfondire il fenomeno di base del deterioramento aerobico e a prospettare e confrontare diverse soluzioni tecniche della sua prevenzione. Sono previste Indicazioni applicative per la conservazione dei foraggi e itinerari tecnici per la riduzione del deterioramento aerobico di insilati di mais e di erba da fornire ai tecnici delle associazioni di produttori e allevatori. Questi protocolli potranno contribuire, se applicati su larga scala aziendale, a migliorare la qualità del latte dal punto di vista microbiologico e a ridurre i problemi nel processo di caseificazione di formaggi tipici, quali il Grana Padano. La fattiva collaborazione delle aziende agricole coinvolte nel Progetto e dei responsabili del Caseificio Quaglia ha permesso di ottenere, in questi tre anni di ricerca, delle indicazioni importanti sulla gestione aziendale degli insilati al fine di contenere il deterioramento aerobico. Il deterioramento aerobico oltre ad essere una perdita diretta di prodotto, rappresenta anche un pericoloso sito di moltiplicazione di clostridi anticaseari e di accumulo delle principali micotossine. Da questa ricerca è emerso un chiaro aumento dei valori di zearalenone nelle aree dei sili soggette a deterioramento aerobico. Anche per quanto riguarda l'aflatossina B1 esistono evidenze relative ad un possibile aumento della tossina negli insilati di mais. Questo aspetto è di notevole importanza sia per la qualità del latte sia per i risvolti che questo può avere sulla salute umana: proprio per questo motivo l'argomento richiederebbe ulteriori approfondimenti sperimentali. Dalle prove di caseificazione a partire separate è emerso come gli insilati di mais soggetti a notevoli deterioramenti, possano influenzare i livelli di contaminazione del latte, determinando un netto aumento della presenza di microrganismi anticaseari. Vista l'estrema importanza e l'attualità delle problematiche trattate, nonché l'ampia diffusione del deterioramento aerobico in azienda, le unità operative coinvolte nel progetto hanno pensato di realizzare una guida pratica per la corretta gestione degli insilati aziendali. L'obiettivo è quello di fornire un supporto gestionale ai tecnici e agli stessi allevatori al fine di limitare e prevenire i danni che il deterioramento aerobico provoca sull'intera filiera produttiva.

Commercial mixed feeds for light horse feeding are more and more used and, in recent times, a particular role is played by mixed feeds characterized by high fibre percentages together with pre-biotic or pro-biotic supplements. Consequently, more data about these new feeds are required. The apparent digestibility of a commercial mixed feed containing about 14 % crude fibre (CF) as fed and lactulose 1% was determined by means of 3 in vivo digestibility trials each performed on 4 saddle horses weighting about 550 kg over a 6 days faeces total collection period with a previous 14 days adaptation period. The diets were based on a first cut meadow hay - whose digestibility was estimated in the first trial - and the mixed feed at a feeding level close to maintenance. The forage to concentrate ratio was, respectively, 100:0, 75:25 and 50:50 in the three trials. Apparent digestibility of dry matter, organic matter, gross energy, crude protein, NDF, ADF and CF were measured by the ingesta/excreta procedure. Data was processed by ANOVA; no significant differences were found between the digestibility trials