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In the present study we estimated the genetic parameters of enteric methane emissions (EME) traits predicted from milk fatty acid profile (FA) and those of their predictors in 1,091 Brown Swiss cows reared on 85 farms in order to assess the potential of using EME-related phenotypes in selective breeding. Univariate and bivariate genetic models were fitted in a Bayesian framework. The means of the marginal posterior distribution of intra-herd heritability ranged from 0.12 for estimated methane production (g/d/cow) to 0.24 for estimated methane yield (g/kg dry matter intake [DMI]), with intermediate values for estimated methane intensity, increasingly higher when expressed per kg of corrected milk (0.13), fresh cheese (0.16), or cheese solids (0.20). Regarding the correlations, the milk quality traits and percentage cheese yields were generally moderately correlated with the estimated EME traits, and were variable in terms of sign. Daily milk and cheese yield traits were, as expected, all highly positively correlated with estimated daily methane production. In contrast, they were negatively correlated with estimated methane yield and intensity, the estimates being large in the case of phenotypic and herd correlations, and low in the case of additive genetic and residual correlations. With the exception of the negative correlations with daily methane production, EME traits exhibited trivial correlations with body size and BCS of cows, which, in turn, were negatively correlated with milk yield. Although the results should be validated on a larger population and different breeds, our study demonstrate the presence of additive genetic variation of EME traits, which could be exploited in breeding programmes for the improvement in both milk production and the ecological footprint of dairy farming.Highlights Enteric methane emissions (EME) of dairy cows can be estimated on the basis of milk fatty acid profile. EME exhibited exploitable genetic variation. Genetic selection could be preferentially based on predicted methane intensity per kg of milk, or per kg of cheese in countries where milk production is used mainly for cheese-making.

Authentication of dairy systems is of growing interest for the dairy industry and we investigated the potentiality of using volatile fingerprinting of ripened cheeses by proton transfer reaction time-of-flight mass spectrometry. A total of 1,075 individual model cheeses made from milk of individual Brown Swiss cows of 72 farms were analysed. Using a linear discriminant analysis, cows and herds were assigned to 3 or 5 dairy systems differing in management, available facilities, and diets. We obtained variable discrimination abilities (up to 77% of correct classification of cheeses and 70% of farms with cross-validation). We found m/z 61,028 (acetic acid), 109,070 (pyrazine), and m/z 137,132 (terpene) characterising model cheeses from traditional dairy systems and m/z 71,086 (3-methyl-butan-1-ol, 3-methyl-3-buten-1-ol, pentan-1-ol), m/z 101,097 (hexan-2-one, hexanal), m/z 123,117 (nonenal), m/z 129,127 (octan-1-one, octanal), and two unidentified peaks m/z 83,071 and m/z 93,090 characterising model cheeses from the modern farms. In conclusion, it seems possible to discriminate between a range of dairy systems using fast volatile fingerprinting of ripened cheeses but a proper validation of results obtained is needed.Highlights Mass spectrometry technique (PTR-ToF-MS) was able to discriminate between dairy systems. We found m/z 61,028 (acetic acid), 109,070 (pyrazine), and m/z 137,132 (terpene) characterising model cheeses from traditional dairy systems. We found m/z 71,086 (3-methyl-butan-1-ol, 3-methyl-3-buten-1-ol, pentan-1-ol), m/z 101,097 (hexan-2-one, hexanal), m/z 123,117 (nonenal), m/z 129,127 (octan-1-one, octanal), and two unidentified peaks m/z 83,071 and m/z 93,090 characterising model cheeses from the modern farms.

Survival analysis methodology was applied in order to analyse sources of variation of preweaning survival time and to estimate variance components using data from a crossbred piglets population. A frailty sire model was used with the litter effect treated as an additional random source of variation. All the variables considered had a significant effect on survivability: sex, cross-fostering, parity of the nurse-sow and litter size. The variance estimates of sire and litter were closed to 0.08 and 2 respectively and the heritability of pre-weaning survival was 0.03.

This study aimed to estimate trends of heterosis for milk yield traits and somatic cell score (SCS) in the Dutch dairy cattle. First lactation data on 305-d milk, fat, and protein yield, and on average 305-d SCS recorded on pure Holstein Friesian (HF), Dutch Friesian (DF), Mosa Reno Yssel (MRY), and F1 crossbreds (DFxHF and MRYxHF) were considered. According to cows’ year of calving, productive records from animals calving from 1980 to 2004 were divided in five periods, while SCS records from animals calving from 1990 to 2004 were divided in four periods. Data were processed using analysis of variance (ANOVA) according to a linear model which included effects of herd, season of calving, age at calving, and the genotype by period of calving interaction effect. Moreover, a linear covariate of sire’s estimated breeding value (EBV) for 305-d milk yield was added to the model for yield traits. Heterosis values for productive traits were positive but decreased over time. For 305-d milk yield these values changed from 7.5 to 3.0% in the DFxHF crossbreds, and from 9.0 to 1.0% in the MRYxHF crossbreds. Average heterosis for SCS (-1.2%) was small and negative with a favourable trend over years.

Several local sheep breeds of the Alpine regions are in danger of extinction as a result of mountain farms being abandoned. Three fattening trials were carried out on 4 breeds of the Veneto region (Foza, Lamon, Alpagota, and Brogna) on a total of 115 ewes and suckling lambs, weaned lambs and heavy lambs slaughtered at 1356 ± 267, 104 ± 24, 219 ± 26, and 342 ± 14 d of age, respectively. The results confirmed that the adoption of total mixed diets resulted in good in vivo and post mortem performances of culled ewes (64 kg slaughter weight, 48% dressing percentage), suckling lambs (21 kg, 50%), weaned lambs (30 kg, 42%) and heavy lambs (61 kg, 48%). Carcass compactness and fatness increased with the age of the lambs, whereas the proportions of lean meat and bone decreased. Meat lightness and cooking losses decreased with age, whereas redness and chroma increased. The meat quality of culled ewes was like that of heavy lambs. Carcass conformation and composition (aside from size traits), and the quality of the meat differed little among the four Alpine breeds. These results show that local breeds are potentially valuable sources of lamb and mutton meat across different seasons, paving the way for strategies to develop and promote the meat with the involvement of high-quality restaurants and meat retailers.Highlights Compared to outdoor grazing, the adoption of indoor diets resulted in good in vivo and post-mortem performances of ewes, suckling lambs and heavy lambs. Autochthonous Alpine breeds are potentially valuable sources of high-quality lamb and mutton across different seasons of the year. This potential could be exploited in developing a prestigious product aimed at high quality restaurants and butchers. The subsequent demand for the product would, in turn, contribute to the survival of the local sheep breeds of Alpine regions.

To promote local food products could be a valuable strategy for preserving autochthonous sheep breeds. A total of 115 lambs and ewes of local sheep breeds (Alpagota, Bogna, Foza and Lamon) of the Veneto region were used to evaluate the effect of different feeding systems on the production and quality of lambs and mutton meat. We carried out three fattening trials involving 24 ewes and their 31 suckling lambs, 24 weaned lambs, and 24 heavy lambs, fed indoor diets with or without a rumen-protected conjugated linoleic acids (rp-CLA) supplement (C18:2c9,t11 and C18:2t10,c12) to improve the nutritional value of the meat. Controls were a group of 12 pasture-fed weaned lambs. The weaned lambs at pasture had good fattening performances (33 kg live-weight at slaughter, 45% dressing percentage), whereas lambs fattened indoors on hay and some concentrates had lower weight (28 kg) and dressing percentages (41%), and require improvements to their feed. Feeding the animals on total mixed diets resulted in good in vivo and post mortem performances of culled ewes (64 kg slaughter weight, 48% dressing percentage), suckling lambs (21 kg, 50%) and heavy lambs (61 kg, 48%), showing that valuable supplies of lamb and mutton meat can be obtained across different seasons. Supplementing indoor diets with rp-CLA does not modify the animals’ performances nor the organoleptic traits of meat.Highlights Intensive indoor fattening allows to obtain suckling, weaned and heavy lambs and mutton from culled ewes all-year-round beyond the seasonal supplies of traditional feeding system. The supplementation of indoor diets with rp-CLA does not modify the animals’ performances, slaughter traits or meat organoleptic traits.

This study aimed at investigating the effects of growth rate (GR) on live performance, carcass and dressed green ham (DRHAM) traits of finishing heavy pigs managed in accordance with the regulations governing the production of Protected Denomination of Origin (PDO) dry-cured hams. Data were obtained from 233 crossbred pigs restrictively fed from 90 to 165 kg BW. Individual BW, daily feed intake, and weights of carcass and main cuts were recorded. Thighs were measured for subcutaneous fat thickness, analysed for fatty acid composition of subcutaneous fat, and dry-cured hams were weighed. Records were classified according to GR quartile, calculated using the residuals of a statistical model that included the effects of pen, sex and diet. Data were analysed using the same model with the addition of the effect of GR quartile. Average GR ranged from 578 in the first quartile to 748 g/d in the fourth. Final BW and weights of carcass, DRHAM and dry-cured ham increased as the GR quartile increased (p

The milk Fourier-transform infra-red spectrometry (FTIRS) can be used to predict the enteric methane emissions (EME) at population level. In this study, the variability in FTIRS predicted EME traits due to the breed of cow, farm, the production level of individual cows within herds, and their interactions were evaluated. A dataset obtained from milk recordings, which covered four breeds (Holstein, Brown Swiss, Simmental and Alpine Grey), 6,430 herds, 115,819 cows, and 1,759,706 test-day milk/spectra records was used. The herds were stratified into 5 production levels considering their average daily milk energy production; individual cows within herd were similarly stratified considering their individual production levels. The EME traits were predicted directly from milk FTIR spectra or indirectly from six informative milk FA predicted from milk spectra. The statistical model included, separately for each trait and method, breed, herd intensiveness level, cow production level, and their interactions, year, month, parity, and lactation stage. The direct and indirect methods yielded similar results in predicting CH4 yield per kg of DMI and CH4 intensity per kg of fat-protein corrected milk. The indirect method was reliable in predicting daily EME production per cow, the indirect one did not. EME was affected by the breed x herd production intensiveness interaction, and to a lesser degree, by the breed x cow production level interaction. A better understanding of the complex interactions influencing EME in dairy herds was achieved. This would be useful for the genetic improvement, the environmental certification of farms, and for setting prices in milk payment schemes. Causes of variation of the FTIR predicted EME were studied at population level using data from 6,430 herds and 1,759,706 milk spectra records Reliable daily EME estimates were achieved from 6 six informative fatty acids predicted from milk spectra EME was influenced by the interaction breed × level of herd intensiveness and, to a lesser extent, by the individual production level [ABSTRACT FROM AUTHOR]

The use of sexed semen to produce replacement heifers in dairy farms allows many cows to be inseminated with bulls of beef breeds with the aim of improving meat production. The major dairy and beef breeds are undergoing rapid genetic improvement as a result of more efficient selection methods, necessitating evaluation of the quality of meat produced by beef × dairy crosses obtained using current genetics. As part of a larger project, we carried out quantitative and qualitative evaluations of the veal and beef produced from crossbred calves produced by dairy farms that use sexed semen to obtain purebred replacement heifers. A total of 231 bull-calves were reared in the dairy farms or in specialised fattening farms, slaughtered, and sampled for meat quality analysis. These comprised: 104 crossbred calves, mainly from Belgian Blue sires and Holstein dams, which were intensively fattened for veal production; 84 beef × dairy crossbred calves, destined for beef production on the dairy farm of origin (12 calves) or in a specialised intensive fattening centre (72 calves); 26 purebred Charolais and 17 beef crosses from suckler cows, included for comparison, which were fattened in the same fattening centre and fed the same diet as the beef × dairy crosses. Veal and beef meat differed in all quality traits; the beef produced by dairy farmers was better than the beef produced by specialised fatteners in terms of cooking losses and tenderness, even though these animals were much older and weighed less at slaughter. There were minor differences in the quality traits of veal between the various beef × dairy breed combinations. In the case of intensive beef production, minor differences were observed between Belgian Blue-sired crosses from Brown Swiss cows (lipid content and shear force of meat) and Belgian Blue-sired crosses from crossbred cows (haem iron, lightness, yellowness, and hue) in comparison with crosses from Holstein cows. The beef of young bulls from suckler cows (Charolais and crosses) had a lower pH, dry matter and lipid contents, slightly higher cholesterol and haem iron contents, and higher cooking losses than meat from beef × dairy crosses. Taking into account the results from the entire project, we conclude that the combined use of sexed semen for pure-breeding and conventional beef semen for terminal crossbreeding improves meat production from dairy herds, both quantitatively and qualitatively. The meat from beef × dairy crossbred calves was found to have valuable qualitative characteristics. With regard to veal production, the meat quality characteristics of crossbred calves did not differ appreciably between breed combinations. With regard to intensive beef production, the meat from beef × dairy young bulls had greater quality than that from suckler cows. Crosses fattened by dairy farmers grew slower than those by specialised fatteners, but their beef was better in terms of cooking losses and tenderness. [ABSTRACT FROM AUTHOR]

Aim of this study was to estimate the sire effect on market value (€/calf) of crossbred calves from Belgian Blue sires and Brown Swiss dams. The dataset accounted for 11,300 calves, progeny of 12 Belgian Blue bulls. Data on live weight (kg), price (€/kg), and market value were analysed with a model that included fixed effects of herd of origin, sire, sex, and age of the calf fitted as a linear covariate, and year and month of auction. Live weight, price, and market value averaged 68.6kg, 6.35€/kg, and 437€/calf, respectively. The market value of male exceeded that of female calves by 82€. Progeny of the worst and the best sire averaged 404 and 452€/calf, respectively. Results of this study shared that the choice of beef bulls should be carefully evaluated to optimize the benefits from crossbreeding.

The aims of this study were to predict beef quality traits (BQ: colour, shear force, drip and cooking losses) of Piemontese cattle using near-infrared spectroscopy (NIRS) and to estimate genetic parameters for measured BQ and their predictions by NIRS. Heritabilities and genetic correlations for measured BQ and their predictions based on NIRS were estimated through bivariate Bayesian analyses. Heritability estimates for measured BQ were of intermediate magnitude (from 0.10 to 0.63) and similar to those for NIRS predictions. The genetic correlations between BQ measures and their predictions by NIRS were very high for colour traits, high for drip loss, and nil for shear force and cooking loss. NIRS predictions can be proposed as indicator traits in breeding programs for enhancement of colour traits and drip loss.

An outbreak of coccidiosis occurred in red-legged partridges is reported. At the post-mortem examination the birds showed a mucous haemorrhagic enteritis, mostly in the duodenal intestinal tract. Direct microscopic examination of intestinal content revealed the presence of a high number of oocysts. After incubation, on the basis of the morphological features, two species of coccidia were identified: Eimeria kofoidi and E. legionensis.

This study investigated the application of mid-infrared spectroscopy for the prediction of protein composition in individual milk samples (n=1,336) of Simmental cows. Protein fractions were quantified by RP-HPLC and MIR data were recorded over the spectral range from 4,000 to 900 cm-1. Models were developed by partial least squares regression using untreated spectra. The most successful predictions were for protein, casein, αS1-casein, whey protein, and β-lactoglobulin contents. The models could discriminate between high and low values of protein composition (R2=0.50 to 0.58). The root mean square errors of cross-validation were 3.11g/l for protein (range 39.91g/l), 2.76g/l for casein (range 35.16g/l), 1.07 g/l for αS1-casein (range 12.82g/l), 0.51 g/l for whey protein (range 4.97g/l), and 0.43 for β-lactoglobulin (range 4.37). Application of MIR spectroscopy is possible for the routinely assessment of protein, casein, αS1-casein, whey protein, and β-lactoglobulin and its implementation might be in future a tool for improving protein composition of bovine milk through breeding programs.

Aim of this study was to characterize the buffalo production in the Veneto region of Italy. Test day records of milk production traits (milk yield, protein, fat, and somatic cell count) of 845 buffalo cows from two herds were analyzed using a linear model. The effects included in the model were herd-test-day, days in milk, and parity. Days in milk was the most important source of variation for milk yield, protein, and fat. The patterns of milk yield traits across lactation followed the typical trend of buffalo cows. Results allowed a preliminary characterization of buffalo production in north of Italy.

An outbreak of coccidiosis occurred in red-legged partridges is reported. At the post-mortem examination the birds showed a mucous haemorrhagic enteritis, mostly in the duodenal intestinal tract. Direct microscopic examination of intestinal content revealed the presence of a high number of oocysts. After incubation, on the basis of the morphological features, two species of coccidia were identified: Eimeria kofoidi and E. legionensis.

In the present study we estimated the genetic parameters of enteric methane emissions (EME) traits predicted from milk fatty acid profile (FA) and those of their predictors in 1,091 Brown Swiss cows reared on 85 farms in order to assess the potential of using EME-related phenotypes in selective breeding. Univariate and bivariate genetic models were fitted in a Bayesian framework. The means of the marginal posterior distribution of intra-herd heritability ranged from 0.12 for estimated methane production (g/d/cow) to 0.24 for estimated methane yield (g/kg dry matter intake [DMI]), with intermediate values for estimated methane intensity, increasingly higher when expressed per kg of corrected milk (0.13), fresh cheese (0.16), or cheese solids (0.20). Regarding the correlations, the milk quality traits and percentage cheese yields were generally moderately correlated with the estimated EME traits, and were variable in terms of sign. Daily milk and cheese yield traits were, as expected, all highly positively correlated with estimated daily methane production. In contrast, they were negatively correlated with estimated methane yield and intensity, the estimates being large in the case of phenotypic and herd correlations, and low in the case of additive genetic and residual correlations. With the exception of the negative correlations with daily methane production, EME traits exhibited trivial correlations with body size and BCS of cows, which, in turn, were negatively correlated with milk yield. Although the results should be validated on a larger population and different breeds, our study demonstrate the presence of additive genetic variation of EME traits, which could be exploited in breeding programmes for the improvement in both milk production and the ecological footprint of dairy farming. Enteric methane emissions (EME) of dairy cows can be estimated on the basis of milk fatty acid profile. EME exhibited exploitable genetic variation. Genetic selection could be preferentially based on predicted methane intensity per kg of milk, or per kg of cheese in countries where milk production is used mainly for cheese-making. [ABSTRACT FROM AUTHOR]

Over recent decades, there was a substantial evolution in the productive management of dairy animals worldwide with a consequent boost in individual milk yield. This evolution positioned the milk production as the central metabolic priority around which all other physiological functions are coordinated and partially minimised. This shift underscores the crucial role of effectively managing stressful phases in intensive dairy farming systems, also highlighting the resilience exhibited by the animals. Indeed, monitoring the nutritional and health status becomes paramount, aiming for an early detection of (sub)clinical health impairments. Given the mammary gland’s centrality in high-yielding dairy breeds, it’s unsurprising that the milk matrix provides insights about udder itself but also systemic metabolic function. The emerging field of milk phenomics explores links between milk components and animal health, holding great promise for studying dairy cow resilience. The use of infrared spectroscopy on milk to predict indicators and complex traits at the herd level is a promising approach. In the dairy sector, the available infrared instruments mainly implement the Fourier transform infrared (FTIR) spectroscopy. This method is widely employed in milk recording schemes worldwide for animal monitoring and breeding purposes. In addition, visible and near-infrared (NIR) spectroscopy is increasingly integrated into milking systems for daily on-farm monitoring of milk quality and animals’ physiological status. This review examines the topic of milk phenomics together with potential and challenges of infrared spectroscopy to predict indicators and complex traits related to health and nutritional disorders exploiting the biological bonds that exist between milk and blood in dairy animals.HIGHLIGHTS Milk is a valuable source of information for assessing nutritional and health proxies in dairy animals. Infrared spectroscopy is used within routine milk recording systems for the determination of major components, but other useful applications exist. This review summarises research on milk phenomics carried out by mean of infrared spectroscopy to predict complex traits related to animals’ health and nutritional disorders.

This study aimed at evaluating the environmental impact (EI) of herds representative of the Italian heavy pig production system to investigate the EI variation associated with farm management (FM), diet formulation (DF) and animal response (AR) variables. Data originated from 8 breeding farms, which included the sows and preweaning piglets (Site1) and the post-weaned piglets (7.5–30 kg body weight – BW, Site2) and 10 growing–fattening farms, dealing with 30–170 kg BW pigs (Site3). A cradle-to-farm gate Life Cycle Assessment was used, with 1 kg BW gain (BWG) as functional unit. Impact categories were global warming (GWP), acidification (AP) and eutrophication (EP) potentials and land occupation (LO). Whole-production cycle EI (Site123, 0–170 kg BW) was obtained summing up EIs of 0–30 and 30–170 kg BW animals. Impacts were analysed with one- or two-way PERMANOVA to test the effect of FM, DF and AR variables. The Site123-related EI averaged nearly 3.1 kg CO2-eq (GWP), 50 g SO2-eq (AP), 22 g PO4-eq (EP) and 4.9 m2/y (LO) per kg BWG. Site3 contributed nearly 80% of the whole impact. Regarding Site1, GWP resulted mitigated by increasing sow productivity. Site2 EI resulted mitigated by decreasing feed conversion ratio and increasing average daily gain, whereas Site3 EI by increasing feed self-sufficiency and decreasing dietary crude protein and mortality. In perspective, given the relevance of Site3 on the whole-pig system EI, a deeper integration between the farm agronomical management and the growing–finishing pigs’ diets formulation would support the environmental sustainability of heavy pig operations.

The milk Fourier-transform infra-red spectrometry (FTIRS) can be used to predict the enteric methane emissions (EME) at population level. In this study, the variability in FTIRS predicted EME traits due to the breed of cow, farm, the production level of individual cows within herds, and their interactions were evaluated. A dataset obtained from milk recordings, which covered four breeds (Holstein, Brown Swiss, Simmental and Alpine Grey), 6,430 herds, 115,819 cows, and 1,759,706 test-day milk/spectra records was used. The herds were stratified into 5 production levels considering their average daily milk energy production; individual cows within herd were similarly stratified considering their individual production levels. The EME traits were predicted directly from milk FTIR spectra or indirectly from six informative milk FA predicted from milk spectra. The statistical model included, separately for each trait and method, breed, herd intensiveness level, cow production level, and their interactions, year, month, parity, and lactation stage. The direct and indirect methods yielded similar results in predicting CH4 yield per kg of DMI and CH4 intensity per kg of fat-protein corrected milk. The indirect method was reliable in predicting daily EME production per cow, the indirect one did not. EME was affected by the breed x herd production intensiveness interaction, and to a lesser degree, by the breed x cow production level interaction. A better understanding of the complex interactions influencing EME in dairy herds was achieved. This would be useful for the genetic improvement, the environmental certification of farms, and for setting prices in milk payment schemes.HIGHLIGHTS Causes of variation of the FTIR predicted EME were studied at population level using data from 6,430 herds and 1,759,706 milk spectra records Reliable daily EME estimates were achieved from 6 six informative fatty acids predicted from milk spectra EME was influenced by the interaction breed × level of herd intensiveness and, to a lesser extent, by the individual production level

Avian Pneumovirus (APV) is the casual agent of Turkey Rhinotracheitis (TRT), and also causes a respiratory infection inchickens, which can result in Swollen Head Syndrome. A survey of APV infection in Italian turkey and broiler farms, in ahighly populated area of Northern Italy (Verona Province) is reported. Nine turkey farms and 6 broiler farms were sampled.Sixteen birds from each group were doubly swabbed from the choanal cleft for virus isolation on tracheal organ cultures(TOC) and RT nested PCR (A and B type specific) using extracted RNA. At the same time blood samples were collectedfor a blocking ELISA serological assay. The broiler samples for virological assays were treated with infectious bronchitisvirus (IBV) antiserum raised against serotypes prevalent in the areas sampled, thus avoiding competitive growthof IBV on TOC. Ciliostasis on TOC was taken as the indicator of the presence of the virus, and confirmation was by indirectimmunofluorescence. APV was isolated and detected by RT-PCR in 19 day-old turkeys, and in 34, 42 and 48 day-oldbroilers. All APV strains were found to be type B. All turkeys of more than 4 weeks old were APV positive by ELISA. APVinfection was found to be widely spread in the area sampled and the protocol used for virus isolation was shown to beeffective. Turkey rhinotracheitis first appeared in Italy in the late 1980s, and the APV isolates involved were subsequentlycharacterised as B types. Our results confirm APV B type to be present in Italy, but the limited findings to date need tobe extended by further surveys of other Italian regions.

This study aimed to analyse the sources of variation of milking speed assessed through automatic computerised devices included in milking machines, to study the relationships between this trait and milking speed assessed through stopwatch and to develop statistical procedures useful for converting automatic device milking time into stopwatch milking time in order to obtain a fast, simple and cheap collection of milking time records for genetic evaluation purposes. A total of 571 records of stopwatch milking time (SMT), device milking time (DMT) and milk yield at milking were collected in 23 herds of the Trentino Alto Adige region in Italy equipped with two types of automatic milking devices. After log-transformation of SMT (lnSMT) and DMT (lnDMT) and a preliminary analysis of sources of variation of lnDMT, dataset was partitioned into two mutually exclusive subsets: a calibration one, used for statistical analysis, and a validation one, used as test set to validate the prediction models. This procedure was replicated 6 times in order to repeat the cross validation accordingly. Three conversion models have been compared, based on different combinations of the effects of lnDMT, milking device and herd within milking device on lnSMT. Solutions of the models have been applied for each replicate to the validation dataset for estimating lnSMT and the soundness of conversion equations have been evaluated considering the correlation between estimated and actual lnSMT and bias and precision of estimates. Milking time assessed through different procedures resulted in differences between methods for both mean and distribution, and these suggested the need of developing statistical procedures aimed to the conversion of DMT into SMT before their use in sire evaulation. The soundness of the models tended to slightly increase with the increase in the number of effects considered. The correlation between estimated and actual SMT was in the range of 0.80 to 0.86, the estimated bias was close to 0 for all models and the precision, i.e. the average standard deviation of the difference between estimated and actual SMT, in the range of 8-9% of the mean of actual SMT. In conclusion, conversion equations proposed for joining the two sources of information performed satisfactorily, giving rise to SMT accurate estimates, which were not distorted and fairly precise. The use of such equations can support the integration of automatically acquired milking time records into breeding schemes, which is advisable for increasing the number of sires progeny tested and the accuracy of breeding values estimated.