Effects of extruded corn on milk yield and composition and blood parameters in lactating dairy cows

According to a 2x2 cross over design, fourteen Holstein dairy cows at 99±55 DIM were fed two diets containing 21.5% DM of either ground corn (GC) or extruded corn (EC). Performance and metabolic profile were detected during the third week of each experimental period. DMI and milk yield were not affected by dietary treatments. Milk fat and protein percentage of EC diet were significantly (P<0.10) lower than those of GC diet. Probably the higher rumen degradability of starch from EC thesis modified the synthesis of specific fatty acids leading to a milk fat depression event. Diets did not influence blood parameters, except for lower values of total protein and glucose content in EC diet-fed cows. Results suggested that the dietary inclusion of extruded corn should not be used at the tested level of substitution

Effect of the partial replacement of fish meal and oil by vegetable products on performance and quality traits of juvenile shi drum (Umbrina cirrosa L.)

A four-month growth trial was carried out in order to evaluate performance and quality traits of juvenile shi drum fedwith two isonitrogenous and isoenergetic diets having different amounts of vegetable products (Vegetable diet vs. Controldiet). Compared to the Control diet, the Vegetable diet was formulated by increasing the replacement of fish meal (14%)with soybean and cereal products, and fish oil (12%) with a mixture of vegetable oil. On June, 4 groups of 225 fish (2replicates per dietary treatment) were sorted according to live weight and reared in fibreglass tanks over a four- monthlong experimental period. Fish were hand fed to apparent satiety. Offered feed, growth parameters and feed efficiencywere recorded as productive performance. At the end of the trial (October) biometric, chemical and reological traits wereexamined to assess fish quality. The dietary treatments showed similar productive performance. The relatively high inclusionof vegetable sources led to a significant modification of body shape, mesenteric fat and viscera weight. Among qualitytraits, Vegetable diet-fed fish demonstrated a significantly lower whole body and fillet crude protein content.Yellowness value of the cooked fillet was significantly lower in the Control diet-fed fish, whereas fillet texture was similar.The results of this research showed that shi drum is a suitable candidate for Mediterranean marine aquaculture andits dietary formulation might include at least the amount of vegetable sources used in this trial

Effect of non-forage roughage replacement on feeding behaviour and milk production in dairy cows

The objective of this study was to determine whether the partial replacement of roughage from forage with non-forage fiber sources, in a total mixed ration (TMR), could reduce feed sorting by dairy cows without modifying behaviour and milk production. Twelve Holstein cows were fed two TMR maize silage based diets in a cross-over experiment. Compared to the control diet (C-diet), experimental diet (E-diet) was formulated by replacing 8% neutral detergent fibre (NDF) from straw and alfalfa hay with soybean hulls and wheat bran. E-diet had a lower physical effectiveness factor (pef) (0.37 vs 0.34; P<0.001) and physical effective NDF (peNDF) (15.5 vs 14.6%; P<0.01). Feeding and sorting behaviour, ruminal activity, milk yield and composition and blood metabolites were measured. The results indicated that dry matter intake was not affected by diet. Cows fed the experimental TMR spent less time eating (192 vs. 178 min/d; P<0.05) but showed the same number of meals per day. C-diet fed cows sorted against peNDF in a greater extent (98.3 100.9%; P<0.05). Treatments did not affect cows time budget of general behaviors, with particular regard to ruminating activity. Despite different forage sources in TMR, no significant differences in milk yield and quality were detected

Effect of dietary fat level on carcass traits and flesh quality of European Sea Bass (Dicentrarchus labrax) from mariculture

The study aimed at evaluating the effect of the reduction of dietary fat on juvenile European sea bass nutritional value and quality traits. Fish were reared in floating cages (Trieste Gulf, Italy) from July (11) to October (10). Two isoproteic diets were compared: LF (low fat, EE = 19.4%) vs. HF (high fat, EE = 24.6%). No significantly different growth performance was observed. LF diet-fed fish were characterized by the reduction of celomatic fat (not edible fraction) and by the increase in dressing percentage. The tested dietary fat level also affected both fillet and epiaxial white muscle proximate composition, resulting in a significantly lower fillet lipid concentration in LF diet-fed fish. Dietary treatment influenced cooked fillet colour and texture probably as a consequence of the different intramuscular fat deposition. Fillet from HF-fed fish, in fact, presented higher lightness (L*) value and lower instrumental strengthness

1H NMR Metabolic Profile to Discriminate Pasture Based Alpine Asiago PDO Cheeses

The study was carried out in an alpine area of North-Eastern Italy to assess the reliability of proton nuclear magnetic resonance 1H NMR to fingerprint and discriminate Asiago PDO cheeses processed in the same dairy plant from upland pasture-based milk or from upland hay-based milk. Six experimental types of Asiago cheese were made from raw milk considering 2 cows' feeding systems (pasture- vs. hay-based milk) and 3 ripening times (2 months, Pressato vs. 4 months, Allevo_4 vs. 6 months, Allevo_6). Samples (n = 55) were submitted to chemical analysis and to 1H NMR coupled with multivariate canonical discriminant analysis. Choline, 2,3-butanediol, lysine, tyrosine, and some signals of sugar-like compounds were suggested as the main water-soluble metabolites useful to discriminate cheese according to cows' feeding system. A wider pool of polar biomarkers explained the variation due to ripening time. The validation procedure based on a predictive set suggested that 1H NMR based metabolomics was an effective fingerprinting tool to identify pasture-based cheese samples with the shortest ripening period (Pressato). The classification to the actual feeding system of more aged cheese samples was less accurate likely due to their chemical and biochemical changes induced by a prolonged maturation process

Effect of unsaturated fatty acid supplementation on performance and milk fatty acid profile in dairy cows fed a high fibre diet.

The influence of unsaturated fatty acid (UFA) supplement on productive performance, physiochemical properties and fatty acid (FA) profile of milk, was investigated in lactating dairy cows fed with high fibre diets. According to a cross-over design, twelve cows were assigned to two experimental settings characterized by different FA profiles. Cows received a high fibre diet (~42% NDF on DM basis) supplemented with soybean based mixtures with these FA compositions: 92.0% of saturated FA (SFA), 2.8% of monounsaturated FA (MUFA) and 5.2% of polyunsaturated FA (PUFA) in the control diet (C-diet); 19.1% of SFA, 20.9% of MUFA and 60.0% of PUFA in the experimental diet (E-diet). The E-diet did not affect dry matter intake nor milk yield. Milk composition and coagulation traits resulted similar between treatments, except for the lactose level, which was lower in the E-diet (5.0 vs 4.8%; P<0.05) and the freezing point (-0.546 vs -0.535 °C; P<0.05). As respects the milk FA profile, the E-diet significantly increased the percentage of UFA because of their greater amount in the ration; however the "transfer" of UFA in milk was limited by the high level of FA biohydrogenation (BH) at the ruminal level. UFA showed low values of carry over in milk (67.5 vs 39.7%; P<0.001) due to the saturation process; on the contrary SFA had a threefold increment (124 vs 323%; P<0.001), mostly due to a peak in the production of stearic acid. In this study, the percentage of CLA in milk (0.50 vs 0.62%; P<0.05) was quite low for both diets, if compared with other studies, and this was probably due to a low vaccenic acid supply at duodenal level

Effects of axial and ceiling fans on environmental conditions, performance and rumination in beef cattle during the early fattening period

The aim of this study was to assess the effect of two air stirring systems (ceiling fans vs. axial fans) on environment, performance, rumination and activity of beef cattle during the first period after the arrival to the fattening unit. One group of 106 charolais bulls was raised from August to October in a roofed, loose housing facility with straw bedding. Animals were randomly assigned to pens equipped with one of two types of fans: ceiling fans and axial fans. The trial lasted 70 days, and was divided into 3 periods. In the first and third periods fans were in operation, whereas in the second they were switched off. Animals were evaluated for average daily weight gain, cleanliness, dry matter intake, rumination time, activity level and health condition. The temperature-humidity index and the comprehensive climate index were continuously calculated and pens were periodically checked for the dry matter of the bedding. The average temperature-humidity index was lower in the third period (65.5) compared to the first (74.4) and second (75.3) periods (P < 0.001), but was not affected by the air stirring system, while on the contrary the comprehensive climate index was higher in AF than in CF during the first period (27.1 vs. 24.9 °C; P < 0.05). Ceiling fans led to higher dry matter of the bedding in the first (30.6 vs. 45.1%; P < 0.01), second (29.4 vs. 34.3%; P < 0.05) and third periods (22.2 vs. 31.3%; P < 0.05) and to cleaner bulls at the end of the trial. Animals raised with ceiling fans showed higher average daily weight gain (1.20 vs. 1.36 kg/day; P = 0.039), higher daily rumination time in the first period (431 vs. 475 m; P < 0.01) and patterns of rumination and activity compatible with a lower level of heat stress. Based on these results, it appears that ceiling fans are promising tools to be used to reduce heat stress and optimize performance of beef cattle

use of rumination and activity data as health status and performance indicators in beef cattle during the early fattening period

Abstract The aim of this study was to measure the level of activity and rumination in young bulls and to assess whether these data can be used as indicators of health status and average daily weight gain (ADG). Two groups of animals (period 1: n = 108 animals; period 2: n = 106 animals) were fitted with sensors to measure daily activity and rumination, were weighed on arrival and at the end of the trial (70 days) and were checked twice daily to verify their health condition. Any clinical signs and therapies were recorded. The dishomogeneity index of rumination (DR), and the daily dishomogeneity indices of activity (DDA) and rumination (DDR), were calculated. Bulls had an ADG of 1.42 ± 0.38 kg/day and showed an average duration of daily rumination of 404 ± 63 min and an average activity of 474 ± 46 bits, respectively. Animals characterised by low ADG had lower values of minimum daily rumination ( P = 0.01) and DDA ( P 0.001), and a greater rumination range ( P = 0.007) and DR ( P = 0.003). Bovine respiratory disease and lameness were detected 31 and five times, respectively; among affected animals, the average daily activity, rumination and DDA were lower ( P 0.05) at 3–6 days before the onset of visible clinical signs, whereas DDR increased compared to the values when individuals were apparently healthy. The use of individual sensors appears promising for the early diagnosis of disease in beef cattle and for improving herd management

Lecithin: a by-product of biodiesel production and a source of choline for dairy cows

The aim of the present study was to compare the effects of soy lecithins (L), a by-product of the biodiesel production process, and choline chloride microencapsulated with hydrogenated vegetable oils (C) on dry matter intake, milk yield, milk quality traits, milk choline and haematological profile of dairy cows. A total of 12 mid-lactating Holstein Friesian cows were assigned to one of two experimental groups and fed according to cross-over design (2 diets x 2 periods). Diets were isoenergetic, isofibrous and isonitrogenous and had the same content of choline. Dry matter intake was not affected by the diet, but L led to lower milk choline (P<0.05) and to a significantly higher milk yield (P<0.05), although the 3.5% fat-corrected milk (FCM) did not change owing to the higher content of fat in the milk of the C-diet group (P<0.01). The remaining milk components were unaffected by the supplements, except for the milk urea, which was lower in the L-diet group (P<0.01), reflecting a more effective use of degradable proteins by the micro-organisms present in the rumen. With regard to the haematological profile, L led to lower urea (P<0.001) and to higher values of glucose (P<0.01) and non-esterified fatty acids (NEFA)/Cholesterol ratio (P< 0.05), but all of the values fell within the physiological range of lactating dairy cows. Results indicated that soy lecithins can be used as an available and cost-effective source of choline in mid-lactating dairy cows

Blood Parameters Modification at Different Ruminal Acidosis Conditions

This study evaluated the reliability of various blood parameters to assess the ruminal acidosis in cattle. Six whole heifers were fed three experimental rations in a 3 x 3 Latin square design. The diets had different starch levels: high (HS), medium (MS) or low (CT). Ruminal pH values were continuously measured using wireless sensors. To evaluate the severity of ruminal acidosis, the amount of time per day that the pH was below 5.8, 5.5 and 5.0 was recorded. Blood samples were analyzed for complete blood count, venous blood gas and biochemical profile at 8:00 and 12:00 h. The data were analyzed according to a mixed model. Feeding on CT, MS and HS led to significant differences in DMI (7.7 vs. 6.9 vs. 5.1 kg/d; P < 0.01) which modified the amount of time per day that the pH was below 5.0 (0 vs. 12 vs. 92 min; P < 0.10). Feeding MS and HS diets led to inflammation as indicated by the significant increment of white blood cells when compared to the CT ones and to blood concentration due to the osmotic pressure at ruminal level. Furthermore a significant decrease of bicarbonate level, CO2 partial pressure and oxyhemoglobin was observed as consequence of the activation of metabolic processes aimed to prevent metabolic acidosis. No differences were observed on blood sampling time, suggesting that one daily blood sample was enough to evaluate the metabolic variations related to ruminal acidosis