Monica Isabella Cutrignelli

Influence of pasture on fatty acid profile of goat milk

The effect of pasture on the fatty acid profile of milk was evaluated using 30 pluriparous goats, which were divided into two homogeneous groups (H and P) of 15 goats each after kidding. Group H (control) goats were housed in a stall and received alfalfa hay, while group P was led to pasture. The goats of both the groups received the same concentrate. Average milk yield did not differ statistically between the groups. The goats of the P group had significantly higher fat content in milk than those of group H (53.7 vs. 61.5 g/day, p < 0.01), while lactose content was significantly higher for group H (66.2 and 61.4 g/day, for groups H and P, respectively, p < 0.05). Among milk fatty acids, pasture significantly affected the percentages of C18:1 cis9, C18:1 trans11, octadecadienoic acid, mono-unsaturated fatty acid and polyunsaturated fatty acid. Pasture highly influenced the c9 t11 conjugated linoleic acid (CLA) (0.778 and 0.513 g/100 g of fat, for group P and H, respectively, p < 0.01), t10 c12 CLA (0.046 vs. 0.029 g/100 g of fat: p < 0.01, for group P and H, respectively, p < 0.01) and SigmaCLA (0.84 vs. 0.56 g/100 g of fat for group P and H, respectively, p < 0.01) concentrations of milk.

Fermentation kinetics of sainfoin hay with and without PEG

The in vitro gas production technique was applied to evaluate the biological activity of tannins in sainfoin (Onobrychis viciifolia Scop.) hay cut at four progressive phenological stages. The buffalo (Bubalus bubalis) rumen fluid was used as inoculum, polyethylene glycol (PEG) was added as specific binding agent and an alfalfa hay (AH) was used as control. All samples were analysed for chemical composition and condensed tannin (CTs). According to the phenological stage of sainfoin, crude protein gradually decreased [from 219 to 122 g/kg dry matter (DM)] and neutral detergent fibre (NDF) increased (from 391 to 514 g/kg DM). Condensed tannins showed the highest value at the first phenological stage [31.5 mg catechin equivalents (CE)/g DM], and their level significantly decreased at the subsequent growth stages. Gas production and fermentation rate were significantly affected by substrate type and PEG addition. The first stage of sainfoin showed the lowest value of gas and volatile fatty acids production and the slowest fermentation kinetics compared with the other samples, when incubated without PEG, because of the CTs effect. The incubation with PEG improved the fermentation process of the first stage of sainfoin, but no effect was registered on AH, where CTs were not detected. Among the sainfoin samples, the slowest kinetics with PEG was observed in the hay harvested at the fourth stage, probably due to its chemical composition. The use of PEG allowed to verify the effect of tannins on the in vitro fermentation characteristics of sainfoin hay.

In vitro fermentation characteristics of diets with different forage/concentrate ratios: comparison of rumen and faecal inocula.

BACKGROUND The aim of this trial was to evaluate the replacement of rumen fluid with faeces as inoculum in studying the in vitro fermentation characteristics of diets for ruminants using the in vitro gas production technique. Six iso-protein diets with different forage/concentrate ratios were incubated with rumen fluid (RI) or faeces (FI) collected from sheep. RESULTS Most of the fermentation parameters were influenced by diet and inoculum (P < 0.01). With both inocula, organic matter degradability (dOM), cumulative gas production (OMCV) and maximum fermentation rate (R(max) ) increased as the amount of concentrate in the diet increased. R(max) was lower with FI vs RI (P < 0.01); dOM was higher with FI vs RI and the diet × inoculum interaction was significant. As expected, with both inocula, R(max) increased as the neutral detergent fibre content of the diet decreased. Significant correlations were obtained using both inocula between OMCV/dOM and gas/volatile fatty acid (VFA), while the correlation VFA/dOM was significant only with FI. The microbial biomass yield calculated by stoichiometric analysis for all diets was higher with FI vs RI. With FI the organic matter used for microbial growth showed an overall decreasing trend as the amount of concentrate in the diet increased. CONCLUSION The results indicate that both faeces and rumen fluid from sheep have the potential to be used as inoculum for the in vitro gas production technique.

Physical and chemical quality of ostrich eggs during the laying season.

1. Fifteen ostrich females were monitored for a full breeding season. At 30, 70, 110, 150 and 210 d from the beginning of laying, one egg per female was taken to the laboratory to assess its physical and nutritive characteristics. 2. The average length was 15·4 cm, while the width was 12·9 cm. Average shell thickness ranged from 2·20 mm at the equator to 2·24 mm at the small pole. The three principal components of the egg (albumen, yolk and shell) amounted to 57·1, 23·3 and 19·6%, respectively. None of the above variables, despite showing some significant differences between sampling periods, showed a clear trend linked to the laying season. 3. In contrast, the dry matter of the albumen showed a correlation with the sampling period, increasing from 11·1% in the first period to 12·0% in the last. The crude protein content ranged from 47·7 to 48·2%, the fat from 43·8 to 44·2% and the ash between 5·2 and 5·5% of dry matter. 4. The fatty acid composition of the yolk showed the presence of C18:1 (from 122·0 to 136·4 mg/g), followed by C16:0 (from 40·8 to 46·0 mg/g), C18:0 (from 19·2 to 21·2 mg/g) and C18:2 (from 17·1 to 19·6 mg/g). The content of cholesterol/g of yolk was between 10·6 and 10·9 mg. 5. In conclusion, compared with the hens egg, the ostrich egg has similar chemical and nutritive characteristics, but a higher unsaturated/saturated fatty acid ratio and lower cholesterol content.

Rumen fermentation and degradability in buffalo and cattle using the in vitro gas production technique

An in vitro trial was conducted to investigate the effect of different inoculum sources (buffalo vs. cattle) on rumen fermentation and degradability. Incubations were carried out using rumen fluid obtained from buffalo or cattle fed the same diet [60% grass hay and 40% concentrate; 18 kg dry matter (DM)/day]. The fermentation kinetics of eight feeds commonly used in ruminant nutrition (alfalfa hay, barley meal, beet pulp, corn meal and silage, ryegrass hay and silage and soya bean meal s.e.) were studied with the in vitro gas production technique and rumen fermentation parameters (substrate disappearance, pH and volatile fatty acids production) were determined after 120 h of incubation. The linear relationship indicates that the microbial metabolic pathways of the two inocula for all the substrates were qualitatively similar, albeit often quantitatively different. In this in vitro study, a significant influence of rumen inoculum (buffalo vs. cow) on fermentation and degradability of the examined substrates was found. The differences in buffalo and cattle rumen fermentation can be explained with a different microbial activity of the two ruminant species, because of different amount of microbial population or microbial population constituted by different species of bacteria and protozoa.

Meat quality of buffalo young bulls fed faba bean as protein source

Sixteen Italian Mediterranean Buffalo young bulls were divided into two groups fed isoprotein and isoenergy diets and only differing for protein source of concentrate: faba bean (FB) vs soybean (SB). Animals were slaughtered at 350 kg BW. Meat from FB group showed significantly lower fat, protein, cholesterol and saturated fatty acids than SB group. Significant differences were also found between the three muscles analysed [Longissimus thoracis (LT), Semitendinosus (ST) and Iliopsoas plus Psoas minor (IP)]. ST showed the most favourable fatty acids profile: lower SFA, higher PUFA, MUFA, ω-3, ω-6, CLA and, consequently, lower values for both atherogenic and thrombogenic indexes. Results showed that faba bean can be used as a protein source alternative to soybean in the diet of young buffalo bulls for the production of high quality meat.

In vitro fermentation characteristics of different carbohydrate sources in two dog breeds (German shepherd and Neapolitan mastiff)

Few studies have been published on the normal intestinal biota of canines unlike the wealth of information regarding livestock animal species. The in vitro gas production technique (IVGPT) including measurements of accumulating gas during fermentation and end-product determinations allows obtaining a complete picture of microbial activity kinetics. The aim of this study was to study the in vitro fermentation characteristics of different carbohydrate sources using inocula from two dog breeds (German Shepherd and Neapolitan mastiff). Faeces sampled from rectum of two GS and NM adult dogs, fed the same dry food, were used as inocula. The samples, diluted and filtered, were incubated at 39 degrees C under anaerobic condition with nine substrates different for carbohydrate composition (rice, corn, potato, spelt, pure cellulose, beet pulp, wheat bran, inulin and fructo-oligosaccharide). Gas production was recorded 17 times using a manual pressure transducer. After 48 h, the fermentation was stopped and fermenting liquor was analysed for pH and volatile fatty acids (VFA). Organic matter digestibility (OMD) was calculated as difference after burning the residuals. OMD, gas production and end-products were significantly correlated with chemical composition of substrates, in particular carbohydrate fractions (total dietary fibre and starch), confirming the effectiveness of the IVGPT in evaluating dog feeds. Concerning the comparison between breeds significant differences (p < 0.01) were found for OMD, gas production, fermentation kinetic parameters and end-products, suggesting a different pathway of fermentation and consequently, a different anaerobic population.

Urinary excretion of purine derivatives in dry buffalo and Fresian cows

Abstract Aim of this paper was to compare urinary purine derivatives (PD) excretion in Italian Mediterranean dairy buffaloes and Fresian dairy cows during dry period. Six buffalo and six dairy cows at about 60 days to delivery were housed in individual cages and fed the same diet. Feed intake was monitored daily. After a period of adaptation, total daily urine was collected, weighed, sampled in test-tubes and frozen up to HPLC analysis. During the urine recovery period the daily feed intake was higher for dairy cows (kg/DM 9.0 vs 7.6) even if differences were not significant due to the high individual variability. Urine excretion was significantly (P<0.01) higher in buffaloes than in cow. Total urinary excretion of PD in buffalo was 11% of that of dairy cow (23.707 mmol/l vs 2.711 mmo/l in dairy and buffalo cows, respectively), however the incidence of uric acid was similar in both species. In order to explain the low concentrations of PD in the urine of buffaloes, we investigated also the presence of allantoic acid, final product of purine degradation in several fish species. However it was not detected.

Fermentation characteristics of several carbohydrate sources for dog diets using the in vitro gas production technique

Fermentable carbohydrates are an important part of the canine diet. They can improve gastrointestinal health by modifying gut microbial population and metabolic activity. The present study compared the fermentation characteristics and kinetic patterns of 10 carbohydrate sources using the in vitro gas production technique (IVGPT) with dog faecal inoculum. The substrates tested were: pure cellulose (PC), carboxymethylcellulose (CMC), sugar-cane fibre (SCF), beet pulp (BP), wheat bran (WB), fructooligosaccharides (FOS), inulin, yeast cell wall (YCW), ground psyllium seed (PS), pea hulls (PH). All substrates were incubated at 39°C under anaerobic conditions with faeces collected from dogs as microbial inoculum. Gas production of fermenting cultures was recorded and after 48 h, pH, shortchain fatty acids (SCFA) and organic matter disappearance (OMD) were determined. The results confirm high fermentation by dog faecal bacteria of FOS and inulin that produced high amounts of propionate and that underwent very rapid fermentation. Three substrates (SCF, CMC and PC) were not able to support bacterial growth, with low gas and SCFA production, and high BCFA formation. The PH and BP showed moderate OMD and SCFA production. Wheat bran B underwent rapid fermentation and generated a high proportion of butyrate. Psyllium seeds underwent slow fermentation with delayed gas production, supporting a high formation of SCFA, with an adequate amount of butyrate for bacterial growth while YCW, which showed a delayed fermentation, gave moderate SCFA production. The fermentation characteristics of PS and YCW suggest their potential use in promoting a more distal fermentation on intestinal tract.

Effects of two protein sources and energy level of diet on the performance of young Marchigiana bulls. 2. Meat quality

Abstract The aim of this trial was to study the influence of two protein sources (faba bean-FB vs soybean meal s.e.-SBM) and two energy levels of diets given to young Marchigiana bulls on meat quality: water holding capacity (WHC), chemical composition, hydroxyproline and cholesterol contents, fatty acids profile of intramuscular, subcutaneous and perirenal adipose tissues. While chemical composition and WHC was determined only on muscle Longissimus thoracis (LT), hydroxyproline and cholesterol contents were evaluated also on muscles Semitendinosus (ST) and Ileopsoas plus Psoas minor (IP). Eighteen young bulls were divided into three groups. Until the slaughter weight (620 kg) was achieved, two groups, FB and SBM, were fed diets with similar protein and energy contents but differing in protein sources, and the third group was fed high energy (HE) diets. Protein sources did not affect meat nutritional characteristics; but meat of group SBM had high hydroxyproline content: 62.6 vs 60.0 mg 100g-1, respectively, for SBM and FB groups (P<0.05), while compression losses were higher for FB group (7.6 vs 5.7%, respectively, for FB and SBM groups; P<0.01). As respects the comparison among content of hydroxyproline in the different muscles: IP, corresponding to the tenderloin, showed significantly lower concentrations than the other muscles (55.2 vs 60.7 and 63.5 mg 100g-1 for IP, LT and ST, respectively; P<0.01). Feeding regimes did not affect muscular cholesterol content (average values of 53.6, 55.5 and 52.1 mg 100g-1 of fresh muscle for FB, SBM and HE, respectively) which was similar to the levels found in meat from specialised Italian beef breeds and lower than those from other breeds. As respects the differences in cholesterol contents among the muscles, IP showed lower contents than other muscles (50.9 vs 54.1, 56.0 mg 100g-1, respectively for IP, ST, LT; P<0.05). The higher energy diets induced higher concentration of saturated fatty acids, in particular of palmitic and of stearic acid, in intramuscular fat which worsened significantly atherogenic (AI) and thrombogenic (TI) indexes (AI: 0.67 vs 0.55, 0.50; P<0.05; TI: 1.98 vs 1.61, 1.32; P<0.01; for HE, FB and SBM groups, respectively), and lower content of hydroxiproline (60.0, 62.6 vs 56.8 mg 100g-1, P<0.01 for FB, SBM and HE groups, respectively). The fatty acid profile of subcutaneous and perirenal adipose tissues was not affected by any of studied factors. A part of feeding scheme adopted, from these results it is possible to formulate a favourable assessment of the nutritional characteristics of Marchigiana meat.