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Forages dry matter (DM) could vary among batches and in particular when silages are fed. These variations could modify nutrients composition of total mixed ration and affect cows performance. The aim of this study was to evaluate the effect of application of a precision feeding system (PFS) based on a near infra-red scanner, on metabolic conditions and milk yield in lactating dairy cows. The study was performed in 7 farms where PFS was installed on feed mixer to perform a weight-adjustment of DM measured in real time on feeds. A cross-over (14 weeks periods) was applied, PFS was switched on (PF-ON) in three herds and off in the other four (PF-OFF) during 1st period, and vice versa in 2nd period. At the end of two periods, in each herd 7 early and 7 mid lactation cows, for a total of 196 cows, were checked for: blood parameters, milk yield and composition. During the study deviation of DM of target diet (calculated on amount of feed in recipe and applying the DM determined in laboratory) and diets really distributed to cows tended to be lower with PF-ON vs. PF-OFF (0.06 vs 0.12 kg, p =.12). In early lactating cows, lower blood urea (4.63 vs 4.88 mmol/L, p =.115) indicated a better feed protein utilisation in PF-ON vs. PF-OFF. Milk yield and composition were not affected. The use of PFS meliorated the consistency of TMR, which could determine a better efficiency of nutrients utilisation and a reduction of production costs.Highlights Near infra-red (NIR) technology can be advantageously applied at farm level within a precision feeding system for dairy cows. The system allowed a more constant daily supply of nutrients with a reduction of metabolic alterations and a higher efficiency of feed protein utilisation. Utilization of NIR technology at farm level can be economically sustainable.

Hail affects yield and quality of maize crops, and consequences also depend on the growth stage at which the injury occurred. Whole-plant maize (WPM) silage is often used within the same farm for cattle feeding and biogas production. The present study aimed to verify the effects of hail damage, simulated by artificial defoliation, on yield and chemical and nutritional features, as well as on biochemical methane potential (BMP) of maize forage. In a randomized block design with three replicates, four defoliation levels (0%, 33%, 66% and 100% of leaf area removal respectively) have been applied at either the V12 (12th leaf), R1 (silking) or R3 (milk) stages for two consecutive years. WPM yield, chemical and nutritional features, and BMP were measured. Dry-matter (DM) yield per hectare was progressively reduced (p < 0.001) with increasing levels of defoliation and with application at V12 in comparison with R1 or R3 (1.26 vs. 1.39 and 1.46 kg ha −1 for V12 vs. R1 and R3; p < 0.003). Nutritive value and BMP per unit of product were less altered than dry-matter yield per hectare by defoliation. Anticipating defoliation reduced net energy for lactation (5.26 vs. 5.46 MJ kg −1 DM for V12 and R3 respectively; p = 0.02). Total defoliation resulted in an accumulation of nitrates (NO 3 ) compared to the other treatments (3.98 vs. 1.53 g NO 3 kg −1 DM; p < 0.001). BMP was mainly reduced by early and complete defoliation. Equations were developed to estimate the effects of defoliation on yield, composition, and nutritive and energetic values of WPM.

Ruminant production has been an essential part of human activities worldwide since ancient times. The expected increase in world population and per capita income, with an increase in the amount and prevalence of animal products in human diet, urbanization, with a concentration of population in urban areas and an increase in losses in the supply chain, and the growing concern over the environmental impact of animal farming require a long-term global strategy for a more intensive and sustainable ruminant production. Therefore, solutions to increase the supply of high-quality products of ruminant origin, without harming human health, animal welfare, and environment, should consider the following interconnected issues discussed in this review: a) effects of meat, milk and dairy products consumption on human health, focusing on the imbalance caused by their insufficient consumption, and the alleged increased incidence of certain diseases due to their consumption; b) importance of the sustainable intensification of ruminant production systems (e.g. better feed conversion and higher production output per unit of input introduced into the farming system); c) environmental impact of ruminant production; d) improvement of animal performance by improving animal welfare; e) adaptation of ruminants to climate change; f) sustainable ruminant feeding (e.g. precision feeding techniques, optimization of grazing systems, and use of unconventional feeds); g) challenges posed by production intensification to animal breeding and conservation of animal biodiversity; and h) strategies to increase ruminant production in developing countries, thus achieving food security in vast areas of the planet affected by fast growth of human population.

The aim of this study was to evaluate the use of Fourier transform mid-infra-red (FT-MIR) spectrometry to analyse blood biochemical parameters of the horse. For this purpose, mid infrared transmission spectra were acquired from plasma samples from 72 healthy horses. Each sample was also analysed using reference clinical chemical methods, and these results were used as calibrating values to develop predictive models by partial least squares method. The validation was carried out using external validation method. The coefficient of determination (R2) and the ratio of prediction to deviation (RPD) showed high values for parameters regarding energy and protein metabolism. Among energy parameters, an excellent prediction model was developed for total cholesterol (R2 = 0.94; RPD = 4.40) and triglycerides (R2 = 0.96; RPD = 5.0) while fair results were obtained for cholesterol fractions (R2 range: 0.75–0.80; RPD range: 2.0–2.3). Among protein metabolism parameters, excellent prediction models were developed for total protein, albumin, globulin (R2 range: 0.96–0.99; RPD range: 5.40–9.30) and good prediction model for urea (R2 = 0.90; RPD = 3.2), confirming previous results with the plasma of dairy cows. Our results highlight that FT-MIR spectrometry offers an accurate measurement of important plasma biomarkers for the evaluation of energy (cholesterol and triglycerides) and protein metabolism (urea), as well as for health status (albumin/globulin ratio). Our results may open an interesting perspective of a more cost-effective approach to monitoring the metabolic status and health conditions of the horse, with the future possibility to predict some blood biomarkers by the practitioner in field.Highlights FT-MIR potential to measure blood parameters in horses was explored; Infra-red spectrometry can be used in horse’s clinical chemistry; Fast and cost-effective metabolic status evaluation in horses; Accurate FT-MIR predictions for plasma protein and lipid fractions in horses.

This study investigated the potential application of Fourier transform mid-infrared spectroscopy (FT-MIR) for the determination of titratable acidity (TA) in cow’s milk. The prediction model was developed on 201 samples collected from cows in early and late lactation, and was successively used to predict TA on samples collected from cows in early lactation and in samples with high somatic cell count. The root mean square error of cross-validation of the model by using external validation dataset was 0.09 Soxhlet-Henkel/50 mL. Applying the model on milk samples from cows in early lactation or with high somatic cell count, the root mean square error of prediction was 0.163 Soxhlet-Henkel/50 mL, with a RER and RPD of 23.9 and 5.1, respectively. Our results seem to indicate that FT-MIR can be used in individual milk samples to accurately predict TA, and has the potential to be adopted to measure routinely the TA of milk.

Background Although a metabolic profile represents a valid tool utilized in dairy herds to determine abnormalities in blood chemistry related to an increased risk of production diseases, there are no studies on application of Fourier Transform mid-infrared (FT-MIR) spectroscopy. This study assesses the potential application of FT-MIR to analyze the main blood biochemical parameters included in the metabolic profile of dairy cows. Infrared transmission spectra were acquired for 35 plasma samples (two replicates on each sample) of Italian Friesian dairy cows (14 primiparous and 21 pluriparous), all without clinical events, and at different stages of lactation, although mainly in the transition phase. Each sample was also analyzed independently using accepted reference clinical chemical methods and these results were used as calibrating values to perform predictive models by PLS method using cross validation. Results Measured blood parameters concentrations were all within the reference ranges reported for healthy dairy cows. The number of extracted factors with the PLS procedure for each prediction model ranged between 3 and 7. The coefficient of determination (R2) of the prediction models ranged between 0.1 to values close to 1. R2 values greater than 0.9 were observed for the prediction models of total cholesterol, total protein, globulin, and albumin; values between 0.75 and 0.9 were observed for urea, NEFA, and total bilirubin, while values of R2 lower than 0.6 were observed for all minerals and for enzyme activity. The range error ratio (RER) and prediction to deviation (RPD) ranged from 5.1 to 43.8 and from 1 to 13.8 for RER and RPD, respectively. Values of RPD greater than 5 were observed for total cholesterol, total protein, albumin, and globulin. RPD ranged between 2 and 5 for the prediction models of urea, NEFA, and total bilirubin, while RPD and RER were low for minerals and enzyme activities. Conclusions Although the results of this study require further v

Milk coagulation properties are used to evaluate the cheesemaking aptitude of milk samples. No international standard procedure exists, although laboratories often mimic the production of a full-fat fresh cheese for milk coagulation properties. Questions have arisen about the predictability of such a procedure for different types of cheese production. The aim of this study was to establish a procedure mimicking the production conditions of a long-ripened hard cheese, taking Protected Designation of Origin Grana Padano as a case study. With respect to the traditional conditions (standard procedure; SP), the Grana Padano procedure (GP) modifications were the use of standardized milk, coagulation lower temperature, previous milk acidification, lysozyme addition, and rennet type. Each modification was tested in turn versus the SP and also all together in the GP. Another 3 tests were carried out: SP on naturally creamed milk, SP with double the quantity of rennet, and a simplified GP on a full-fat milk sample. The 10 procedures were tested on 2 subsamples with 2 replicates each and were repeated using individual milk samples from 15 dual-purpose Simmental cows in 4 sessions for a total of 600 tests. Two Formagraph instruments (Foss Electric A/S, Hillerød, Denmark) measuring curd firmness every 15 s were used, prolonging test duration to 60. min to obtain 5 traditional single-point milk coagulation properties and 3 parameters of the curd firming model using all 240 points recorded for each replicate. The 8 traits of each replicate were analyzed according to a mixed model with fixed effects of 4 sessions, 10 treatments, 2 instruments, and 16. microvats, and random effects of 15 animals and 300 subsamples. Compared with the SP, the coagulation and curd firming was slowed by low temperature and was accelerated by acidification and by adding a double amount of rennet; natural creaming, fat standardization, and rennet with 5% pepsin affected only some traits, whereas lysozyme

Plasma concentration of fructosamine (Fr) has been proposed as a way to monitor retrospective undernutrition in dairy cows during the transition period. The objective of this study was to evaluate, under standard feeding conditions, the variation of plasma Fr in dairy cows during the transition phase and its relationship with biomarkers of energy metabolism and inflammatory conditions. The trial was carried out with 24 Italian Friesian dairy cows from the last month of pregnancy through the first 2 months of lactation. Diet characteristics and dry matter intake (DMI) were continuously monitored, and energy balance was evaluated on a weekly basis. Milk yield, body weight, body condition score and health status were also monitored. Blood samples were taken two times a week throughout the experimental period and daily in the week before and after calving. Concentrations of Fr together with biochemical indicators related to energy, protein and mineral metabolism; markers of inflammation; and liver enzymes were measured in plasma. Cows were categorized into three groups according to the average concentration of plasma Fr observed at 28, 35 and 42 days in milk (DIM) (cows with lowest [LF], intermediate [IF] and highest [HF] concentrations of Fr, respectively). The LF cows reached an average maximum milk yield (MY) of 51.7 kg/d, whereas IF and HF cows produced 48.9 and 47.2 kg/d, respectively. During the first month of lactation, the DMI was 17.4, 18.2 and 18.7 kg/d in LF, IF and HF, respectively. In the first month of lactation, Fr was not correlated with MY, but had a positive correlation with DMI (P < 0.05) and energy balance (P < 0.05). In the same period, the average plasma glucose was greater (P < 0.05) in HF (3.71 mmol/L) and lower in LF (3.34 mmol/L). During the first month of lactation, plasma Fr was positively related (P < 0.05) to plasma glucose and albumin concentrations over the previous 1–3 weeks. The Liver Activity Index, used to measure the consequences of

High temperature influences rumen and gut health, passage rate, and diet digestibility, with effects on fermentative processes. The main aim of the study was to investigate the effect of hot season on hindgut fermentation, the occurrence of Clostridium tyrobutyricum spores in bovine feces, and on their relationship with metabolic conditions in dairy cows producing milk used for Grana Padano cheese. The study was carried out on 7 dairy farms located in the Po Valley (Italy), involving 1,950 Italian Friesian dairy cows. The study was carried out from November 2013 till the end of July 2014. Temperature and relative humidity were recorded daily by weather stations. Constant management conditions were maintained during the experimental period. Feed and diet characteristics, metabolic conditions, and fecal characteristics were recorded in winter (from late November 2013 to the end of January 2014), spring (from April to May 2014), and summer (July 2014) season. In each season, blood samples were collected from 14 multiparous lactating dairy cows per herd to measure biochemical indices related to energy, protein, and mineral metabolism, as well as markers of inflammation and some enzyme activities. Fecal samples were also collected and measurements of moisture, pH and volatile fatty acids (VFA) were performed. The DNA extracted and purified from fecal samples was used to detect Clostridium tyrobutyricum spores in a quantitative real-time PCR assay. The daily mean temperature-humidity index was 40.7 ± 4.6 (range 25 to 55), 61.2 ± 3.7 (range 39 to 77), and 70.8 ± 3.2 (range 54 to 83) in winter, spring, and summer, respectively. Total VFA concentration in feces progressively decreased from winter to summer. The seasonal changes of acetate and propionate followed the same trend of total VFA; conversely, butyrate did not show any difference between seasons, and its molar proportion was greater in summer compared with winter. A greater occurrence of Cl. tyrobutyricum spor

The main objective of this experiment was to monitor the rumination pattern during the summer season in lactating dairy cows and to investigate its relationships with metabolic conditions and physiological markers of heat stress. The study was carried out in an experimental freestall barn located near Piacenza, Italy (45°01′N, 9°40′E; 68 m above sea level), and involved 21 Italian Friesian cows (11 primiparous and 10 multiparous) during the summer season. Rumination time (RT) was recorded by using an automatic system and data were calculated and summarized in 2-h intervals. Microclimatic conditions (temperature and relative humidity) inside the barn were recorded during the trial, and the temperature-humidity index (THI) was calculated. Breathing rates and rectal temperatures were recorded following stable meteorological periods characterized by lower and higher temperatures. At the same times, blood samples were collected to assess biochemical variables related to energy, protein, and mineral metabolism, as well as markers of inflammatory conditions and enzyme activity. Daily milk yield, body weight, nutritional condition, and health status were also recorded. The average RT was 501 min/d, with no significant differences between primiparous and multiparous cows. According to the microclimatic conditions and physiological markers of heat stress, the cows suffered mild to moderate heat stress during the summer. A negative relationship between daily maximum THI and RT was observed (r = -0.32), with a reduction of 2.2 min of RT for every daily maximum THI unit over the threshold of daily maximum THI of 76. Most of the rumination occurred during the night (on average the nighttime RT was 63.2% of daytime and nighttime RT); moreover, the proportion of nighttime RT slightly but significantly increased as THI increased. Rumination time throughout the trial was negatively related to breathing rate and positively related to milk yield. Daily maximum THI was negatively correl

The main objective of this experiment was to monitor the rumination pattern during the summer season in lactating dairy cows and to investigate its relationships with metabolic conditions and physiological markers of heat stress. The study was carried out in an experimental freestall barn located near Piacenza, Italy (45°01′N, 9°40′E; 68 m above sea level), and involved 21 Italian Friesian cows (11 primiparous and 10 multiparous) during the summer season. Rumination time (RT) was recorded by using an automatic system and data were calculated and summarized in 2-h intervals. Microclimatic conditions (temperature and relative humidity) inside the barn were recorded during the trial, and the temperature-humidity index (THI) was calculated. Breathing rates and rectal temperatures were recorded following stable meteorological periods characterized by lower and higher temperatures. At the same times, blood samples were collected to assess biochemical variables related to energy, protein, and mineral metabolism, as well as markers of inflammatory conditions and enzyme activity. Daily milk yield, body weight, nutritional condition, and health status were also recorded. The average RT was 501 min/d, with no significant differences between primiparous and multiparous cows. According to the microclimatic conditions and physiological markers of heat stress, the cows suffered mild to moderate heat stress during the summer. A negative relationship between daily maximum THI and RT was observed (r = -0.32), with a reduction of 2.2 min of RT for every daily maximum THI unit over the threshold of daily maximum THI of 76. Most of the rumination occurred during the night (on average the nighttime RT was 63.2% of daytime and nighttime RT); moreover, the proportion of nighttime RT slightly but significantly increased as THI increased. Rumination time throughout the trial was negatively related to breathing rate and positively related to milk yield. Daily maximum THI was negatively correl

The main objective of this experiment was to monitor the rumination pattern during the transition period in primiparous (PR) and pluriparous (PL) dairy cows and to investigate its relationships with metabolic conditions, milk yield and health status. The study was carried out in an experimental free-stall barn, and involved 32 Italian Friesian cows (9 PR and 23 PL) during the transition phase. The rumination time (RT) was recorded with an automatic system (HR-Tag) and data were calculated and summarized in 2-h intervals. Blood samples were collected during the transition phase to assess biochemical variables related to energy, protein, and mineral metabolism, as well as markers of inflammatory conditions and some enzyme activity. Daily milk yield, body weight, nutritional condition and health status were also recorded. The average RT before calving (-20 to -6 d) was 463 min/d in PR (range 270 to 620) and 522 min/d in PL (range 411 to 640). In the early lactation (15 to 40 DIM), the average RT was 504 min/d in PR (range 400 to 585) and 562 min/d in PL (range 414 to 685), and was positively correlated with milk yield (r = 0.36; P < 0.001). The RT reached the minimum at calving d (262 min/d in PR and 278 min/d in PL). Before calving the percentage of RT during the nighttime was 60% in PR and 62% in PL; while the values decreased after calving (55% in PR and 57% in PL respectively). During the first weeks of lactation, PR showed a lower RT than PL in the 2-h intervals that included milkings. Cows with lower RT before calving maintained lower RT after calving, and suffered a greater frequency of disease than cows with higher RT in late pregnancy. Moreover, cows characterized by mild inflammatory conditions, and without health disorders or only mild health disorders during the puerperium, showed a higher average rumination time (over 520 min/d) during the first ten days of lactation. Conversely, the lower level of rumination time (450 min/d) during the first few days of l

The aim of this paper was to evaluate the effects of three different feeding management (FM) schedules on physiological markers of heat stress (HS), metabolic conditions, milk yield and quality during hot season in dairy cows. The study involved 27 mid-lactating cows, subdivided in 3 homogeneous groups differing for feeding time and frequency: total mixed ration (TMR) delivered once daily in the morning (M); twice daily, half in the morning and half in the evening (ME); once daily in the evening (E). During the trial blood samples were collected in the morning (a.m.) and in the evening (p.m.), breathing rate (BR), rectal temperature (RT), and milk yield were recorded and individual milk samples were collected. Microclimate data indicated that cows were subjected to mild-moderate HS. During the hotter days, cows in M treatment showed higher values of RT (38.97 °C vs. 38.68 °C and 38.62 °C, in ME and E) and BR (71.44 vs. 66.52 and 65.26 breaths min-1, in ME and E), a.m. plasma glucose was lower in M (3.69 vs. 3.83 and 3.83 mmol L-1, in ME and E) and a.m. plasma urea was lower in E (4.82 vs. 5.48 and 5.35 mmol L-1, in M and ME). Milk yield was unaffected by FM, as well as milk composition and cheese-making properties. Only milk protein content and yield were higher in M (3.42 vs. 3.36 and 3.27%; and 1.11 vs 1.08 and 1.02 kg d-1, for ME and E). Our results on cow physiology indicate how M seems the less suitable FM to match cow welfare during the summer season.

The aim of the present experiment was to verify if average daily gain (ADG) can affect body growth and development, fat deposition, metabolic profile and, by interacting with age at first calving (AFC), also milk production in first lactation. A total of 141 Italian Friesian heifers, in two experimental herds, were allotted to 2 feeding regimens formulated for a moderate (M, 0.7 kg/d) or an accelerated (H, 0.9 kg/d) ADG diet from 5 to 15 mo of age. Half of the heifers on M were programmed to be bred at 15 mo (ME), and half at 18 mo (ML) of age; heifers on H were programmed to be bred at 15 mo of age (HE). Every 28 d, body weight (BW), wither height (WH), hip height (HH), body length (BL), and hearth girth (HG) were measured; in those moments and each week from –14 to 70 d after calving (only in one herd), the body condition score was evaluated. In one herd only, metabolic profile was assessed at 9 and 15 mo of age. Growth curve parameters were estimated for BW, HH, BL, and HG for each heifer. Metabolic profiles from both ages (9 and 15 mo) were processed by Principal Components Analysis. At first calving, milk production and composition were recorded. The BW of M heifers grew slower (0.74 vs. 0.83 kg/d) than H heifers, and this difference was reflected also in a faster HG gain in H than M heifers (0.176 vs 0.165 cm/d). The BCS of heifers fed on H diet grew faster than that of heifers fed on M diet by 9 mo of age. At this age, plasma concentration of urea, Ca, Na, albumin, and -glutamyl transferase activity were greater in H than in M heifers. At 15 mo of age, plasma concentration of bilirubin and alkaline phosphatase activity were lower in H heifers than M heifers. At 9 mo, plasma urea concentration was correlated with HH and HG curve parameters. At 15 mo, plasma glucose concentration was correlated with BW curve parameters. Plasma ceruloplasmin concentration was correlated with HH curve parameters at both ages, and with BW curve parameters at 15 mo. The main resul

This summer study aimed to evaluate the effect on dairy cows, kept in a free stall barn equipped with fans and sprinklers in the feeding area, of the delivery rate of misters in a cooling system in rest areas with different bedding materials. Thirty cows were divided into two homogenous groups according to milk yield and kept in two pens: one had beds with sand (SAMM) while the other had straw (STLM). Each pen was equipped with 2 fans (Ø 70 cm, 0.50 kW) and 2 misters (delivery rate of 11.2 and 22.5 L/h in STLM and SAMM, respectively) in the rest area. Microclimatic parameters, rectal temperature (RT), breathing rate (BR), milk yield, and some milk traits were recorded. Behavioural routines of the cows (standing and lying) were also continuously recorded during the hotter days. During the trial, two mild–moderate heat waves were observed. During these hotter periods, the daily maximum temperature recorded in the rest areas was 28.9 in SAMM and 31.2 in STLM, and the daily maximum THI was 78.2 in SAMM and 81.5 in STLM. In these periods, the cows in SAMM compared with those in STLM showed lower BR (P<0.05) and greater rest time (10.2 and 7.8 h/day in SAMM and STLM, respectively). The RT did not differ (38.89±0.29 and 38.88±0.33°C in STLM and SAMM r, espectively). In conclusion, our research suggests that the cooling system using fans plus misters with mild wetting in rest areas with sand as bedding materials reduces heat stress and improves cow comfort.

This study was conducted to determine the effects of either dietary selenium (Se) source or dose on a range of dairy cow metabolic and hematological profiles and their subsequent relationship with oxidative status and environmental temperature. Forty lactating cows, offered the same basal diet, were blocked by days in milk, milk yield and parity and then randomly allocated to 1 of 5 dietary treatments: negative control (CTRL; 0.098 mg Se kg− 1 DM), two levels of Se yeast (SY) supplementation (0.31 and 0.50 mg total Se kg− 1 DM), and two levels of sodium selenite (SS) supplementation (0.31 and 0.50 mg total Se kg− 1 DM). Whole blood samples were taken from all animals at the start of the study (23 March) and after 28, 56, 84, 112, 126, and 140 d. Whole blood samples were analyzed for total Se, glutathione peroxidase (GPX-1) and a range of hematological parameters. Plasma was analyzed for total Se, glutathione peroxidase (GPX-3), metabolites related to energy and protein metabolism, concentration of minerals, enzyme activities, positive acute phase proteins and oxidative status markers. Glutathione peroxidase activity and total Se in whole blood and plasma were greater (P<0.001) in Se supplemented cows than CTRL. The temperature humidity index (THI) values indicate that during the trial cows experienced a slight-mild heat stress. A negative effect of THI on plasma glucose, non-esterified fatty acids (NEFA), thiol groups, plasma Na and K, and leukocyte count was observed. Conversely, a positive effect of THI on aspartate aminotransferase (AST) activity and GPX-3 activity was observed. Lower values (P<0.05) of thiobarbituric acid reactive substances (TBARS) during the hotter period were observed in SY supplemented animals when compared with CTRL and SS. Furthermore, plasma total antioxidants were lower (P<0.05) in SY supplemented animals when compared with SS during the hotter period. Plasma reactive oxygen metabolites were also numerically lower in SY when compared to

Available data suggest that rumination is depressed during heat stress. The aim of our trial was to evaluate the effect of high temperatures on rumination time (RT) using innovative system. The Hi-Tag rumination monitoring system used in this study consists of rumination loggers positioned on the neck, stationary readers, and software for processing the electronic records. The system summarizes the RT in 2-h intervals. This study used 60 Italian Friesian cows in mid-lactation, raised in a private herd of 286 dairy cows, and fed TMR once daily. Data were collected during summer and the total daily RT, the daytime and nighttime RT were calculated. Daily minimum, mean and maximum temperature were recorded as well as individual daily milk yield (MY). The data were processed using mixed procedure for repeated measures as well as linear and quadratic regressions using RT as dependent variable and daily temperature, MY and DIM. During the trial two hotter periods (HP) were observed. During HP the daily maximum temperature ranged between 32.8 to 38.1° C and the daily minimum temperature ranged between 19.6 to 24° C. Overall total daily RT was 516 ± 87 min d-1 (281 ± 52 and 234 ± 48 min d-1 during nighttime and daytime, respectively). During HP the total daily RT and the daytime RT were significantly lower than the values observed before and after those periods. Overall MY was 21 ± 7 kg d-1 and daily MY was correlated with the total daily RT (r=0.30; P<0.001). A quadratic effect of daily temperature on total daily RT and on daytime was observed, but not on nighttime RT. The temperature, MY and DIM explain the 10% of the RT variability, highlighting that the decline of the RT was non considerable till to a minimum daily temperature of 18° C and to a maximum daily temperature of 28° C. In conclusion high temperatures impact negatively on RT, thus this effect has to be considered during summer to counteract the greater risk of digestive upsets.

The objective of this experiment was to evaluate the effect of the reduction of dietary crude protein (CP), to strictly cover the metabolizable protein requirement, on milk production and efficiency of N utilization. The study involved 28 mid-lactating Italian Friesian dairy cows and was conducted as a cross-over design comprising two periods of 28 d each. The cows were assigned (14 per treatment) to one of 2 isoenergetic dietary treatments (TMR based on corn silage): basal diet (B) and Low Protein diet (LP) containing 15.5 and 14.2 % of CP (DM basis), respectively. Average daily DMI and N intake of each treatment was calculated on a weekly basis. Individual milk yield was recorded daily, and milk samples were weekly collected and analyzed. Average daily secretion of N in milk (g/d) was calculated on a weekly basis. Equation based on urea clearance rate was used to estimate urinary N excretion on a weekly basis. Blood samples were collected at the end of each period and analyzed. Data were processed using mixed procedure for repeated measures. Neither milk yield nor milk protein content were negatively affected by the dietary CP. The urea content in milk and blood (22.4 vs 28.5 and 23.8 vs 30.7 mg/100 mL, in LP and B respectively; P<0.001) was affected by the dietary treatment. The estimated N urinary excretion (both as g d-1 and as percentage of N intake) was lower in LP than in B; conversely, the overall average efficiency of N utilization was greater in LP (33.8 vs 31.1% of N output with milk in percentage of N intake in LP and B respectively; P=0.05). In conclusion results highlighted that a dietary CP lower than the practice standard feeding does not reduce milk yield of mid-lactating cows, improves the efficiency of N utilization, and reduces N urinary excretion.

The cheese-making aptitude of milk depends on chemical composition, renneting properties, bacteriological and fermentability traits. The aim of our research was to study the relationships between dairy cows rearing conditions and milk cheese-making features, with particular attention to the natural aptitude of milk to be fermented by lactic acid bacteria (i.e. acidification rate; AR). This study was carried out on 12 dairy herds identified through a preliminary investigation on 56 herds: six characterized by slow (L) and six by fast (R) AR of bulk milk. Besides AR measurement on bulk milk of each farm, the following determinations were performed: fat, protein, casein, lactose, urea, somatic cell count, titratable acidity and rennet clotting properties. Furthermore, checks on feeds and diets as well as on DM and pH of the feces, collected from six cows per farm (3 in early and 3 in advanced lactation), were carried out. In L farms the rations had a greater content of concentrates, fermentable carbohydrates and crude protein and lower content of NDF. The pH of feces was lower (P<0.001) in L (6.06) compared with R (6.35). Greater milk protein content (3.40 vs. 3.23%; P=0.07) and casein (2.65 vs. 2.48%; P<0.05) were observed in L compared with R; conversely, worse rennet clotting features were observed in the former (clotting time: 22.1 vs. 17.8 min, P=0.06; curd firmness: 17.4 vs. 24.6 mm; P=0.08). Milk urea was greater (P=0.07) in L (34.6 mg/dl) compared with R (24.4 mg/dl). In conclusions the diets characterized by greater fermentable carbohydrates with low pH of the feces (i.e. effect of fermentation in the digestive tract), despite a probable positive contribution on milk protein content, seem negatively associated with the acidification rate and the rennet clotting features.

The milk cheese-making aptitude depends on physico-chemical, bacteriological and fermentability traits, including the natural aptitude of milk to be fermented by lactic acid bacteria (i.e. acidification rate; AR). This trial aimed to evaluate the effect of dietary carbohydrates composition and crude protein (CP) on milk traits, in particular on AR. The trial involved 6 Italian Friesian mid-lactating dairy cows reared in an experimental barn. A crossover (21 d per period) was used to compare B with L diet, characterized by different forage:concentrate ratio (respectively 52:48 vs. 62:38 DM basis), carbohydrate composition (23.9 vs. 20.3% starch; 34.8 vs. 37.5% NDF on DM) and CP content (15.5 vs. 15.1% on DM). Individual dry matter intake (DMI) and milk yield (MY) were measured daily. Milk samples were collected twice a week and analyzed for: fat, protein, casein, lactose, somatic cell count, urea, titratable acidity (SH), renneting properties and AR. Fecal samples were also collected at the end of each period and analyzed for pH and DM. Lower MY (27.9 vs. 30.6 kg/d; P<0.001) and lower DMI (21.2 vs. 23.2 kg/d) was observed in L compared with B. The fecal pH values indicate that digestive processes were not altered by the diets. High values of milk fat and protein content were observed, with lower protein (P<0.05) in L (3.59%) than B (3.66%), with effect on SH (3.61 in L vs. 3.70 °SH/50 mL in B; P<0.05) and curd firming rate (7.5 in L vs. 5.7 min in B; P<0.05). The diet did not modify milk AR, which was lower than the optimal value. Our results confirm that high fermentable diets, if well balanced, do not alter digestive functions and animal health. The reduction of dietary fermentable carbohydrate and CP slightly reduced protein content and SH, but did not modify milk AR.

The relationship between plasma glutathione peroxidase (GPX-3), inflammatory markers and oxidative status in plasma was investigated on 40 Italian Friesian dairy cows. The cows were subdivided in 5 groups: S3 and S5 contained Se yeast S. cerevisiae CNCM I-3060 (0.31 and 0.50 mg of total Se/kg DM respectively); N3 and N5 contained sodium selenite (0.31 and 0.50 mg of total Se/kg DM respectively); C as negative control (0.09 mg Se/kg DM). Before the start of the study and after 84, 126, and 140 d, blood samples were collected and plasma analyzed for GPX-3, Se, positive (+APP) and negative (-APP) acute phase proteins, reactive oxygen metabolites (ROM), thiobarbituric acid reactive substances (TBARS) and thiol groups (SHp). Data were processed using mixed procedure for repeated measures, and multiple stepwise regression using GPX-3 as dependent variable. Lower value (n.s.) of GPX-3 was observed in C (263 U/l) vs. organic Se (275 and 282 U/L in S3 and S5, respectively) and inorganic Se (305 and 304 U/L in N3 and N5, respectively). The GPX-3 was positively correlated with +APP (haptoglobin: P<0.001; ceruloplasmin: P<0.001), and negatively with albumin (P<0.001). Positive correlations between GPX-3 and ROM (P<0.001), and negative between GPX-3 and SHp (P<0.001) were observed. The GPX-3 variability was mainly explained (51.2%) by haptoglobin content; conversely the contribute of plasma Se was only 3.7%. A negative relationship between +APP/-APP ratio and SHp as well as between -APP/+APP ratio and TBARS was observed; these relationships were significant only in C, N3 and N5 diets. In conclusion our results highlighted that GPX-3 was greatly affected by inflammatory conditions, and also seem to suggest a lower oxidative stress in relation to the inflammatory conditions in Se yeast cows.

This study was conducted to determine the effects of dietary Se source and dose on metabolic and hematological profiles, and their relationships with oxidative status in horses. Twenty-five mature horses were blocked by BW and randomly allocated to 1 of 5 dietary treatments: negative control (CTRL: 0.085 mg of Se/kg of DM), 3 different dietary concentrations of organic Se provided by Se yeast (SY02, SY03, and SY04 containing 0.2, 0.3, and 0.4 mg of total Se/kg of DM, respectively), and 1 positive control provided by sodium selenite (SS03 containing 0.3 mg of total Se/kg of DM). Horses were fed the same basal diet (6 kg of grass hay and 3 kg of concentrate per horse daily) and received their respective treatments for a continuous period of 112 d. Jugular venous blood samples were collected before the morning feed on d 0, 28, 56, 84, and 112. Whole blood was analyzed for hematological profile, and plasma was analyzed for metabolites of energy, protein, and mineral metabolism; enzymatic activities and metabolites related to liver and muscle damage; and markers of inflammatory and oxidative status. Plasma metabolites related to energy, protein, and mineral metabolism, acute phase proteins, and enzyme activities related to hepatocellular, hepatobiliary, and muscle damage were not affected by Se source or dose. There were no differences among treatments in either reactive oxygen metabolites or thiol group concentrations in plasma. However, a linear decrease (P < 0. 01) in plasma total antioxidants was observed with increasing Se yeast supplementation. Furthermore, total antioxidant concentrations were less in SY03 than SS03 horses (P < 0.05), and were less in SY03 and SY04 than CTRL horses (P < 0.05). These results could be interpreted as an improvement in the preventive antioxidant systems of horses fed Se yeast. Total white blood cell count was not affected by treatment. There was a tendency for horses receiving greater concentrations of Se yeast to have greater lymphoc

This study aimed to determine the effects of either dietary Se source or dose on dairy cow Se status, milk yield and subsequent milk characteristics. Forty lactating cows, offered the same basal diet, were blocked by DIM, milk yield and parity and then randomly allocated to 1 of 5 dietary treatments: negative control (CTRL; 0.098 mg of Se kg−1 DM), 2 Se yeast supplementation (SY03 and SY05, containing 0.31 and 0.50 mg of total Se kg−1 DM, respectively), and 2 sodium selenite supplementation (SS03 and SS05, containing 0.31 and 0.50 mg of total Se kg−1 DM, respectively). During the trial (lasted 140 d), whole blood, plasma, and milk were analyzed for total Se, and whole blood for glutathione peroxidase activity. The proportion of total Se as selenomethionine (SeMet) or selenocysteine (SeCys) in whole blood and milk samples was also determined. Milk constituent, SCC, technological properties and keeping quality were measured on milk samples. Neither source nor dose was seen to affect milk yield, SCC, or milk characteristics. Glutathione peroxidase activity was greater (Pb0.001) in Se supplemented cows than CTRL but no effect of source was observed. Total Se in whole blood, plasma and milk was greater (Pb0.001) in Se yeast than selenite, with higher asymptotic values in Se yeast, and also a greater ratio between Se in milk and Se in blood or plasma (Pb0.001). The time to asymptotic value of total Se in blood and milk was not affected by Se source, although time to asymptotic total Se in plasma was greater in Se yeast than selenite (Pb0.05). The 16.3% of supplemental Se was transferred into milk of SY05 animals whereas only 3.2% in SS05 supplemented animals. In blood SeCys was the main form of Se, and SeMet the main Se form in milk. In blood and in milk SeMet increased only in those animals supplemented with Se yeast, and at the end of the supplementation period values were greater in Se yeast animals than selenite (Pb0.001). These results demonstrate greater levels of S

This study aimed to determine the effects of dietary Se source on goat’s milk and blood Se status, and its subsequent effects on a number of milk characteristics. Ninety lactating dairy goats fed the same basal diet were randomly allocated to 1 of 3 dietary treatments: negative control (CTRL), containing background Se only (dietary concentration of 0.13mgSe kg−1 DM); selenium yeast (SY) as the Se supplement (0.26mgSe head−1 d−1 of Se–yeast individually offered); sodium selenite (SS) as the Se supplement (0.26mghead−1 d−1 of sodium selenite individually offered). The period of supplementation was 112 d. Jugular venous blood samples (before morning meal) and milk samples (a.m. milking) were taken from 10 goats/treatment on d 0, 28, 56, 84 and 112, and milk yields recorded. On d 84 three Italian fresh cheeses were manufactured from bulk milk taken from each treatment. Selenium content of whole blood, plasma, milk and cheese was determined and erythrocyte glutathione peroxidase (GPX-1) activity was also measured. The proportion of Se incorporated as selenomethionine (SeMet) or selenocysteine (SeCys) in pooled whole blood samples was determined on d 0, 56, and 112. Milk samples were analysed for fat, protein, lactose, somatic cell count, thiocyanate and lactoperoxidase activity. Keeping quality of pasteurized milk was measured using pH, clot on boiling and alcohol stability tests. Data were analysed as repeated measures. Both Se sources, when compared to CTRL, increased GPX-1 activity (P < 0.05), the Se content of blood (P < 0.001) and plasma (P < 0.05). However, there were no differences between sources neither on GPX-1 activity nor on the Se content of whole blood and plasma. Despite this lack of difference in total Se in whole blood there were greater increases in blood SeMet contents in SY supplemented animals when compared to CTRL and SS. Milk Se content was only numerically higher in SS when compared to CTRL but greater in SY when compared to both SS and CTRL (P

The assessment of herd welfare is a scientific discipline that is rapidly developing. The scientific community plays an important role in delivering appropriate, repeatable, valid and feasible models for this assessment. Unfortunately, there are different feelings regarding the welfare of animals and it is imperative for its assessment that certain agreement on the meaning of animal welfare is accepted. Then it is necessary to look at the goals of the models of welfare assessment because different goals require a different combination of welfare indicators. The different models for welfare assessment can be categorized broadly into research, legislative requirements, certification systems, and advisory/management tools. These models may have various goals: quantification of welfare, provision of welfare assurance or welfare management. However, it is widely accepted that welfare is best assessed with multiple different measures; therefore, a welfare assessment model for a livestock herd can include two types of measure: a description of the housing system and management (indirect indicators) and data recording on how the animals react to the system (direct indicators). The first type provides information on risk factors for welfare problems. Direct measures on the animals provide information on their response to the environment and are more direct measures of welfare than their counterparts, but direct welfare indicators alone do not point out the causes of impaired welfare. Because welfare is a complex construct, different approaches for the aggregation of the different aspects of welfare have been proposed, although the aggregation in an overall welfare value is not sufficient. The thresholds between acceptable and unacceptable welfare levels have to be included in the model of welfare assessment but it seems useful to set certain minimum standards for each single welfare aspect. Afterward, judging the validity of a common welfare assessment model is important. In

The aim of this study (research funded by Alltech EU Regulatory Affairs Department, trial ref. SEL/DAI/EFF/04/0107/IT; the authors would also like to give special thanks to Ryszard Lobinski, UT2A laboratories, for performing the selenium analyses) was to determine the effect of dietary Se source and dose on selenomethionine (SeMet) and selenocysteine (SeCys) content of milk in dairy cows. The study involved 40 Italian Friesian lactating cows in mid lactation in a randomized complete block design (5 treatments with 8 animals per group): during the 140-day experiment all animals received the same basal diet, which differed only in Se source and dose: SY3 and SY5 (0.31 and 0.50 mg total Se/Kg DM respectively) containing organic Se (Se yeast) produced by Saccharomyces cerevisiae CNCM I-3060 (Sel Plex®); SS3 and SS5 (0.31 and 0.50 mg total Se/Kg DM respectively) containing inorganic Se obtained from sodium selenite; CTRL as negative control (0.09 mg Se/Kg DM). Prior to the start of the study (T0), at 112 (T112) and 140 (T140) d, samples of milk were analyzed (one pooled milk of 8 samples per treatment at T112; two pooled milk of 4 samples per treatment at T0 and at T140) to determine the proportion of total Se comprised as SeMet and SeCys. At T140 the SeMet content of milk was greater (P<0.001) in Se yeast supplemented animals (234 and 366 ng Se/g DM in SY3 and SY5 respectively) than CTRL (93 ng Se/g DM), and than those receiving comparable doses of selenite (96 and 112 ng Se/g DM in SS3 and SS5 respectively). A dose effect with Se yeast was also observed. Conversely, the SeMet content of milk from selenite treatments at T140 did not differ from CTRL. Consequently the proportion of total Se present as SeMet was greater (P<0.05) in Se yeast (56 and 60% of total Se in SY03 and SY05 respectively) than selenite (37 and 40% in SS03 and SS05 respectively) and CTRL (44%). At T140 the SeCys content of milk was greater in Se yeast supplemented animals (44 and 51 ng Se/g DM in SY3

In two experimental herds 141 replacement heifers were reared with the aim of investigating the relationships between growth from 5 to 18 mo of age and metabolic parameters. The heifers of both herds were fed on a moderate ADG (MADG: 0.7 kg/d) or on an accelerated ADG (AADG: 0.9 kg/d) diet. Heifers’ BW, BCS, wither height (WH), hip height (HH), body length (BL), and hearth girth (HG) were recorded every 28 days. At 9 and 15 mo of age a blood sample was drawn for analysing metabolic profile. Data from body measurements were processed by analysis of variance and growth curve analysis, using Laird’s form of Gompertz curve. Metabolic profiles were processed by Principal Components Analysis (PCA), followed by Pearson’s correlation analysis between growth curve coefficients and PCs. The AADG heifers had greater actual ADG (0.83 vs 0.74 kg, P<0.001) and greater daily increase of HG (1.76 vs 1.65 mm, P<0.005) than MADG heifers. From 9 to 18 mo of age, BCS of AADG heifers diet was greater than BCS of MADG heifers (P<0.05). From the comparison of growth curve parameters between ADG groups, only the initial growth rate of HG was affected by diet, and no effect was found on maturation rate. The PCA showed a PC1 mainly composed of total protein and albumin (9 and 15 mo), Na and ceruplasmin (9 mo), glucose and Ca (15 mo). This component was positively correlated (P<0.05) with the maturation rate of the growth functions for BW, WH, HH, and HG.

This paper considers the relationships among growth curve parameters and plasma metabolites in dairy heifers. Sixty Italian Friesian heifers were randomly assigned on two experimental feeding groups to obtain a moderate (0.70 kg/d; M) or a high (0.90 kg/d; H) average daily gain from 5 to 15 mo of age. Every 28 d, heifers were weighed, scored for BCS, and measured for: wither height, hip height, body length, and heart girth. Blood samples were collected at 9 and 15 month of age, then at 14 and 7 days before calving, to be analyzed for plasma metabolites and enzymes. Laird’s growth function was estimated for body size measurements, and Pearson’s correlation coefficients were calculated between b1 (which reflects the initial specific growth rate), b2 (which reflects the maturation rate of the animal), and plasma metabolite concentrations during growth and before first calving. Among the explored blood metabolites and enzymatic activities at 9 and 15 mo of age, those with high correlation with growth curve parameters were glucose, urea, and ceruloplasmin. Both at 9 and 15 mo of age plasma cholesterol and ceruloplasmin concentrations were positively correlated with their respective values before calving (P<0.001). Plasma glucose at 15 mo was negatively correlated with plasma albumin before calving (P<0.001). The curve parameters from skeletal height measurement were correlated with prepartum plasma creatinine concentration, suggesting that this item was affected by the development of skeletal muscles. Before calving, plasma NEFA and BHBA were positively correlated with enzymatic activities and positive acute phase proteins, mainly related to liver function.