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The yield, flavor, and texture of ripened cheese result from numerous interrelated microbiological, biochemical, and physical reactions that take place during ripening. The aims of the present study were to propose a 2-compartment first-order kinetic model of cheese weight loss over the ripening period; to test the variation in new informative phenotypes describing this process; and to assess the effects on these traits of dairy farming system, individual farms within dairy system, animal factors, and milk composition. A total of 1,211 model cheeses were produced in the laboratory using individual 1.5-L milk samples from Brown Swiss cows reared on 83 farms located in Trento Province. During ripening (60 d; temperature 15°C, relative humidity 85%), the weight of all model cheeses was measured, and cheese yield (cheese weight/processed milk weight, %CY) was calculated at 7 intervals from cheese-making (0, 1, 7, 14, 28, 42, and 60 d). Using these measures, a 2-compartment first-order kinetic model (3-parameter equation) was developed for modeling %CY during the ripening period, as follows: [Formula: see text] , where %CYt is the %CY at ripening time t; %CYi and %CYf are the modeled %CY traits at time 0 d (%CYi = initial %CY) and at the end of a ripening period sufficient to reach a constant wheel weight (%CYf = final %CY after 60 d ripening in the case of small model cheeses); kCY is the instant rate constant for cheese weight loss (%/d). Cheese weight and protein and fat losses were calculated as the % difference between the model cheeses at 0 and after 60 d of ripening. The variation in cheese pH was calculated as the % difference between pH at 0 and after 60 d. Dairy system, individual herd within dairy system, and the cow's parity and lactation stage (tested with a linear mixed model) strongly affected almost all the traits collected during model cheese ripening. Milk fat, protein, lactose, pH, and somatic cell score also greatly affected almost all the traits, although kCY was affected only by milk protein. After including milk composition in the linear mixed model, the importance of all the herd and animal sources of variation was greatly reduced for all traits. The proposed model and novel traits could be tested, first, with the aim of establishing new monitoring procedures enabling the dairy industry to improve milk quality-based payment systems at the herd level and, second, with a view to exploring possible genetic improvements to dairy cow populations.

The genetic variant A1 of bovine β-casein (β-Cn) presents a His residue at a position 67 of the mature protein. This feature makes the Ile66-His67 bond more vulnerable to enzymatic cleavage, determining the release of the peptide β-Cn f(60-66), named β-casomorphin 7 (BCM7). BCM7 is an opioid-agonist for μ receptors, and it has been hypothesized to be involved in the development of different non-transmissible diseases in humans. In the last decade, studies have provided additional results on the potential health impact of β-Cn A1 and BCM7. These studies, here reviewed, highlighted a relation between the consumption of β-Cn A1 (and its derivative BCM7) and the increase of inflammatory response as well as discomfort at the gastrointestinal level. Conversely, the role of BCM7 and the effects of ingestion of β-Cn A1 on the onset or worsening of other non-transmissible diseases as caused or favored by still need proof of evidence. Overall, the reviewed literature demonstrates that the "β-Cn A1/BCM7 issue" remains an intriguing but not exhaustively explained topic in human nutrition. On this basis, policies in favor of breeding for β-Cn variants not releasing BCM7 and consumption of "A1-like" milk appear not yet sound for a healthier and safer nutrition.

Milk lactose, pH, somatic cell count (SCC), bacterial count and NaCl are indirect markers of the mammary gland status; they can be used to screen milk quality and its technological properties. The variability of milk composition and coagulation properties from 1272 individual goat milk samples as a function of the udder health indicators was investigated. High lactose concentrations were associated with reduced coagulation time, but weakened curd firmness traits. High pH values impaired coagulation, while high SCC had delayed coagulation time but reduced curd-firming rate. Samples with high bacterial count were characterised by softer curds, but had faster curd-firming and larger syneresis rates. High concentrations of NaCl were associated with reduced fat, protein, and casein content, and impaired coagulation traits. These results show that the concurrent analysis of these markers can be highly informative and suitable to monitor the quality of milk destined for cheese-making.

Dairy cattle breeds have been exposed to intense artificial selection for milk production traits over the last fifty years. In Italy, where over 80% of milk is processed into cheese, selection has also focused on cheese-making traits. Due to a deep-rooted tradition in cheese-making, currently fifty Italian cheeses are marked with the Protected Designation of Origin (PDO) label as they proved traditional land of origin and procedures for milk transformation. This study aimed to explore from a genetic point of view if the presence of such diverse productive contexts in Italy have shaped in a different manner the genome of animals originally belonging to a same breed. We analyzed high density genotype data from 1000 Italian Holstein cows born between 2014 and 2018. Those animals were either farmed in one of four Italian PDO consortia or used for drinkable milk production only. Runs of Homozygosity, Bayesian Information Criterion and Discriminant Analysis of Principal Components were used to evaluate potential signs of genetic divergence within the breed. We showed that the analyzed Italian Holstein cows have genomic inbreeding level above 5% in all subgroups, reflecting the presence of ongoing artificial selection in the breed. Our study provided a comprehensive representation of the genetic structure of the Italian Holstein breed, highlighting the presence of potential genetic subgroups due to divergent dairy farming systems. This study can be used to further investigate genetic variants underlying adaptation traits in these subgroups, which in turn might be used to design more specialized breeding programs.

Natural variations in milk minerals, their relationships, and their associations with the coagulation process and cheese-making traits present an opportunity for the differentiation of milk destined for high-quality natural products, such as traditional specialties or Protected Designation of Origin (PDO) cheeses. The aim of this study was to quantify the effects of the native contents of Ca, P, Na, K, and Mg on 18 traits describing traditional milk coagulation properties (MCP), curd firming over time (CFt) equation parameters, cheese yield (CY) measures, and nutrient recoveries in the curd (REC) using models that either included or omitted the simultaneous effects of milk fat and casein contents. The results showed that, by including milk fat and casein and the minerals in the statistical model, we were able to determine the specific effects of each mineral on coagulation and cheese-making efficiency. In general, about two-thirds of the apparent effects of the minerals on MCP and the CFt equation parameters are actually mediated by their association with milk composition, especially casein content, whereas only one-third of the effects are direct and independent of milk composition. In the case of cheese-making traits, the effects of the minerals were mediated only negligibly by their association with milk composition. High Ca content had a positive effect on the coagulation pattern and cheese-making traits, favoring water retention in the curd in particular. Phosphorus positively affected the cheese-making traits in that it was associated with an increase in CY in terms of curd solids, and in all the nutrient recovery traits. However, a very high P content in milk was associated with lower fat recovery in the curd. The variation in the Na content in milk only mildly affected coagulation, whereas with regard to cheese-making, protein recovery was negatively associated with high concentrations of this mineral. Potassium seemed not to be actively involved in coagulation and the cheese-making process. Magnesium content tended to slow coagulation and reduce CY measures. Further studies on the relationships of minerals with casein and protein fractions could deepen our knowledge of the role of all minerals in coagulation and the cheese-making process.

Simple Summary It is well known that cattle breeds can produce milk with significant differences in casein and fat contents that are reflected in higher or lower cheese yields. However, the different cheese-yielding ability also involves some particular breed-related molecular characteristics that are not yet considered in milk quality payment systems, due to difficulties in their measurement. The aim of this research was to propose a method for the comprehensive quantification of the effect of milk characteristics on the cheese-making efficiency, including those connected to molecular peculiarities, in terms of casein units. In particular, the method was applied to Parmigiano Reggiano cheese by comparing two different cattle breeds, Italian Friesian and Italian Brown. Under the same processing conditions, the cheese-making efficiency of Italian Brown was higher than that of Italian Friesian. The study concluded that the added value of Italian Brown milk can be expressed in terms of +0.20 g/100 g casein. The method developed could be easily used at the dairy farm level. Abstract Milk from different cattle breeds can present different casein and fat contents, which are reflected in different cheese yields (CY). However, CY is also related to some breed-related molecular characteristics. The aim of the present work was to quantify the effect of these characteristics by comparing a series of Parmigiano Reggiano (PR) cheese-making trials made with milks from Italian Brown (IB) and Italian Friesian (IF) cattle herds. Twelve trials were carried out in a cheese factory in one year (one trial per month), each one consisting of four vats processed in parallel: three vats contained milk from three different IF cattle herds (IF1, IF2 and IF3) and one contained milk from a single IB cattle herd. A 24-h CY prediction formula was developed with data from IF1, IF2 and IF3 trials (calibration) and successively validated by applying it to 12 PR trials made with IF milk in six different cheese factories (external validation). The predicted values of 24-h CY were no different to the actual ones in both calibration and external validation. Finally, the formula was tested on trials made with IB milk. In this case, the predicted values were lower than the actual ones. The quantity of IF milk casein necessary to give the same CY of IB milk was 0.20 g/100 g.

An important problem in mountain areas is the abandonment of pasture. This trend can be combated by the valorisation of typical dairy products, such as &ldquo, Formaggella della Valle di Scalve&rdquo, a semi-cooked traditional cheese made from whole milk in a mountain area in Italy. The aim of the present research was to compare the fatty acid (FA) profile and the sensory properties of this cheese as manufactured under different conditions: i) from the milk of cows grazing on mountain or valley pasture or fed indoors, ii) from the milk of cows fed hay or fed silage. In the first case, five cheesemaking trials were conducted during two years for each of the following situations: mountain pasture (A), pasture at the bottom of the valley (P) (about 1000m asl), stall (S). In the second case, three cheesemaking trials were conducted for each of the following situations: cows fed silage (I), cows fed hay (F). S cheese was richer in medium-chain FAs, while long-chain FAs were higher in P and A cheeses. On the other hand, long chain fatty acids (LCFA) were more abundant in P and A cheeses than in S. In general, MUFA, PUFA and, consequently, total unsaturated FA (UFA), were significantly higher in the P and A cheeses than S (UFA: 36.55 and 38.34, respectively, vs 31.13, p &lt, 0.001), while SFA showed higher values in S (68.85 vs 63.41 and 61.68 in P and A, respectively, 0.001). Conjugated linoleic acid isomers (CLA) were more represented in the P and A samples (1.86 in P and 1.52 in A, vs 0.80 in S, 0.001), Omega 3 fatty acids, and in particular &alpha, linolenic acid, were more abundant in P than in S cheese. In winter, the I sample (silage) presented higher percentages of myristic (C14), myristoleic (C14:1) and omega 6 acids, whereas F cheese (hay) contained higher concentrations of CLA. The triangular test of sensory analysis showed that, in general, F cheeses were judged as &ldquo, sweeter&rdquo, than I, with aromatic profiles characterized by higher content of 2- butanol and ethyl capronate.

The aim of this study was to assess the influence of the amounts of the αS1-, αS2-, β-, and κ-casein (CN) and the α-lactalbumin and β-lactoglobulin protein fractions on the efficiency of the cheese-making process independently of their genetic polymorphisms. The study was carried out on milk samples from 1,271 Brown Swiss cows from 85 herds classified into 4 categories according to management, feeding, and housing characteristics (traditional and modern systems). To assess the efficiency of the cheese-making process, we processed the milk samples according to a laboratory cheese-making procedure (1,500 mL/sample) and obtained the following measures: (1) 3 percentage cheese yields (%CYcurd, %CYsolids, %CYwater), (2) 2 daily cheese yields obtained by multiplying %CY (curd and total solids) by daily milk yields (dCYcurd, dCYsolids), (3) 4 measures of nutrient recovery in the curd (RECfat, RECprotein, RECsolids, RECenergy), and (4) 2 measures of cheese-making efficiency in terms of the ratio between the observed and theoretical %CY (Ef-%CYcurd, Ef-%CYsolids). All the aforementioned traits were analyzed by fitting 2 linear mixed models with protein fractions as fixed effects expressed as percentage in the milk (model M-%milk) and as percentage of the total casein content (model M-%cas) together with the effects of total casein content (only in model M-%cas), daily milk yield (only in model M-%milk; not for dCY traits), dairy system, herd (random effect), days in milk, parity, and vat. The efficiency of overall cheese yield (Ef-%CYcurd) was mostly positively associated with β-CN content in the milk, whereas Ef-%CYsolids was greater with higher amounts of κ-CN and αS1-CN (M-%milk) due to the strong influence of both fractions on the recovery rate of milk components in the curd (fat and total solids, protein with αS1-CN only) when expressed as percentage of milk and of total casein; only β-CN was more important for RECprotein. In contrast, we found β-lactoglobulin to be highly negatively related to all the traits related to the cheese-making process and to the daily cheese yield per cow, whereas α-lactalbumin was positively associated with the latter traits. Additional research on this topic is needed, with particular focus on the genetic and genomic aspects of the role of protein fractions in the cheese-making process and on the associations between genetic polymorphisms in milk protein and milk nutrient recovery in the curd.

Little is known about the complex process of cheesemaking at the individual level of dairy goats because of the difficulties of producing a high number of model cheeses. The objectives of this work were (1) to study the cheesemaking ability of goat milk; (2) to investigate the variability of cheesemaking-related traits among different farms; (3) to assess the effects of stage of lactation and parity; and (4) to compare 6 breeds of goat (Saanen and Camosciata delle Alpi for the Alpine type; Murciano-Granadina, Maltese, Sarda and Sarda Primitiva for the Mediterranean type) for their cheesemaking ability. For each goat (n = 560) we studied (1) 8 milk quality traits (fat, protein, total solids, casein, lactose, pH, somatic cell score, and bacterial count); (2) 4 milk nutrient recovery traits (fat, protein, total solids, and energy) in curd; (3) 3 actual cheese yield traits (fresh cheese, cheese solids, and cheese water); (4) 2 theoretical cheese yield values (fresh cheese and cheese solids) and the related cheesemaking efficiencies; and (5) daily milk yield and 3 daily cheese yield traits (fresh cheese, cheese solids, and water retained in the curd). With respect to individual animal factors, farm was not particularly important for recovery traits or actual and theoretical cheese yield and estimates of efficiency, whereas it highly influenced daily productions. Parity of goats influenced daily cheese production, whereas DIM slightly affected recovery as well as percent and daily cheese yield traits. Breed was the most important source of variation for almost all cheesemaking traits. Compared with those of Alpine type, the 4 Mediterranean breeds had, on average, lower daily milk and cheese productions, greater actual and theoretical cheese yield, and higher recovery of nutrients in the curd. Among Alpine type, Camosciata delle Alpi was characterized by greater nutrients recovery than Saanen. Within the 4 Mediterranean types, the 3 Italians produced much less milk per day, with much more fat and protein and greater recovery traits than the Murciano-Granadina, resulting in greater actual cheese yield. Within the Italian breeds, milk from Sarda and Sarda Primitiva was characterized by lower daily yields, higher protein and fat content, and greater recoveries of nutrients than Maltese goats. These results confirmed the potential of goat milk for cheese production and could be useful to give new possibilities and direction in breeding programs.

This Research Communication investigated the potential of mid-infrared spectroscopy to predict detailed mineral composition of bovine milk. A total of 153 bulk milk samples were analysed for contents of Ca, Cl, Cu, Fe, K, Mg, Na, P and Zn. Also, soluble and colloidal fractions of Ca, Mg and P were quantified. For each milk sample the mid-infrared spectrum was captured and stored. Prediction models were developed using partial least squares regression and the accuracy of prediction was evaluated using both cross- and external validation. The proportion of variance explained by the prediction models in cross-validation ranged from 34% (Na) to 77% (total P), and it ranged from 13% (soluble Mg) to 54% (Cl−) in external validation. The ratio of the standard deviation of each trait to the standard error of prediction in external validation, which is an indicator of the practical utility of the prediction model, was low and never greater than 2. Results from the current study supported the limited usefulness of mid-infrared spectroscopy to predict minerals present in low concentration in bulk milk. For major mineral components, results from the present research did not match previous findings demonstrating the need for further studies using larger reference datasets.

Ca, P and Mg content and distribution between soluble and colloidal phases of donkey milk (DM) were investigated in 62 individual milk samples collected from 9 Ragusano donkeys followed from the second to the ninth month of lactation. Ca (69%) and P (64%) were mainly associated with casein, while Mg was largely found in the soluble form (69%). Only 25% of the colloidal P was present as phosphorylated residues of caseins (casein-P). The colloidal contents of Ca, casein-P, inorganic P (as a constituent of the colloidal calcium phosphate; CCP) and Mg were 1.84, 1.30, 0.45 and 0.15 mmol g casein −1 , respectively, revealing a high level of mineralisation of DM casein micelle. The colloidal Ca to colloidal inorganic-P ratio was 1.51, suggesting that most colloidal Ca was in the form of CCP. All parameters were affected by the period of lactation, except casein level in milk and its level of phosphorylation.

The objective with this research was to compare milk quality parameters among herds characterized by different levels of milk production. The research involved 1080 bulk milk samples collected from 30 dairy herds, which produce milk for Parmigiano Reggiano cheese, during three years. Each milk sample was analysed for fat, crude protein, titratable acidity, total bacterial count, somatic cells, coliform bacteria, and Clostridia spores. Least mean values were obtained by ANOVA using milk production intervals from 6000 to 7999 (L-group), from 8000 to 9999 (M-group), and from 10000 to 12000 kg/cow/lactation (H-group) as fixed milk production classes. Increased milk production was associated with a reduction in milk fat content (from 3.54 in the L-group milk to 3.29 g/100 g in the H-group milk). An improvement in the hygienic-sanitary quality of milk was observed with increasing milk production. In fact, a progressive decrease in the total bacterial count (from 95 in the L-group milk to 45 103 cfu/mL in the H-group milk), number of coliforms (from 2294 in the L-group milk to 1342 cfu/mL in the H-group milk), and somatic cell number (from 382 in the L-group milk to 209 103 cells/mL in the H-group milk) was observed with the increase in milk production level. Finally, it appears that higher milk yield is connected with significant positive effects on the lactodynamometric properties of milk.

Donkey milk is increasingly being proposed as a natural alternative milk for various categories of consumers, especially infants and the elderly population. However, its potential production, gross, and mineral composition have not been deeply investigated yet. Sixty-two individual milk samples were collected monthly from nine Ragusano donkeys reared in a specialized dairy farm. Milk yield as well as chemical and mineral composition, including macro and micro elements, were investigated over an entire lactation, from the second to the ninth month of milking. Milk yield averaged 1.64 kg/day, which highlights good aptitude of the Ragusano breed for the production of milk. Gross composition was characterized by low content of dry matter (8.19%), a high amount of lactose (6.07%), low protein (1.34%), and very low-fat content (0.16%). Whey proteins represented 58% of the total protein, and proteose-peptones accounted for 0.35 &plusmn, 0.07 g per 100 g. Total ash content was 0.36 g per 100 g and represented 4.40% of the dry matter. The most abundant element was K, which was followed by Ca, Na, and P. As expected, the micro elements Fe, Zn, and Cu were found in low amounts or in traces. Dry matter, fat, whey proteins. The total ash, Ca, P, Mg, and mineral ratios were significantly affected by the lactation stage.

The assessment of the efficiency of the cheese-making process (ECMP) is crucial for the profitability of cheese-factories. A simple way to estimate the ECMP is the measure of the estimated cheese-making losses (ECL), expressed by the ratio between the concentration of each constituent in the residual whey and in the processed milk. The aim of this research was to evaluate the influence of the season and cheese factory on the efficiency of the cheese-making process in Parmigiano Reggiano cheese manufacture. The study followed the production of 288 Parmigiano Reggiano cheese on 12 batches in three commercial cheese factories. For each batch, samples of the processed milk and whey were collected. Protein, casein, and fat ECL resulted in an average of 27.01%, 0.72%, and 16.93%, respectively. Both milk crude protein and casein contents were negatively correlated with protein ECL, r = &minus, 0.141 (p &le, 0.05), and r = &minus, 0.223 (p &le, 0.001), respectively. The same parameters resulted in a negative correlation with casein ECL (p &le, 0.001) (r = &minus, 0.227 and &minus, 0.212, respectively). Moreover, fat ECL was correlated with worse milk coagulation properties and negatively correlated with casein content (r = &minus, 0.120, p &le, 0.05). In conclusion, ECLs depend on both milk characteristics and season.

This study examined the milk quality of the autochthonous cattle breed Modenese (MO) in comparison with Italian Friesian (IF), at peak and mid lactation, with the aim to support the interest in sustainability of the local cattle breeds in Europe. Forty-eight individual milk samples were collected from 11 MO and 14 IF pluriparous cows, housed in a free stall barn under similar conditions of feeding and management, at 8 and 21 weeks post-calving; daily milk yield (MY) and body condition score (BCS) were individually recorded. Breed differences were observed, being MY lower in MO cows, but BCS, titratable acidity, freezing point, casein (MC), total calcium (Ca), total phosphorus (P) and colloidal P contents were higher compared to IF cows. Time affected BCS, MY, milk protein (MP), MC, urea, casein P and the micellar content of colloidal Ca and colloidal inorganic P. A factorial analysis was performed and four common factors were obtained with a cumulative explained variance of 77.7% of the total original. MO milk showed a nutritionally interesting mineral profile and processing properties suitable for the production of typical cheese that could be interesting for improving the interest in the conservation of animal genetic resources.

Lactococcus lactis subsp. lactis 68, Streptococcus thermophilus 93 and Lactobacillus rhamnosus BT68, previously isolated from Traditional Mountain (TM) cheese, were tested for the production of four experimental mountain cheeses, with the aim to assess their effectiveness in leading the TM-cheese-making process. Lactococcus lactis subsp. lactis 68 and Streptococcus thermophilus 93 were used as starter cultures, whereas Lactobacillus rhamnosus BT68 was used as non-starter culture. Three control (CTRL) cheeses were manufactured without adding any starter, according to the traditional cheese-making process; nine, cheeses were produced inoculating the vat milk with the starters (ST), starter and low concentration of non-starter culture (STLC), starter and high concentration of non-starter culture (STHC). Samples of vat milk, cheese after 24 h and 7 months ripening were processed for microbiological counts. Mesophilic cocci were dominant in all 24 h-cheese samples, while a dominance of both cocci and lactobacilli was observed after 7 months ripening. The total genomic DNA was extracted, and a fragment of V1-V3 region was amplified and pyrosequenced. Lactococci and streptococci were the most abundant species, and Lc. lactis ssp. lactis 68 affected the proliferation of milk-resident Lc. lactis ssp. cremoris, during the early fermentation. Lb. rhamnosus BT68 showed to be responsible in reducing the abundance of other Lactobacillus species. Moreover, it likely competed against Sc. thermophilus 93 for the same energetic sources, when added in concentration higher than 5 × 103 CFU/mL milk. The sensorial and fatty acid (FA) composition analysis were performed on cheese samples at the end of ripening, demonstrating that the inoculated cheeses had better sensorial characteristics (aspect, smell, taste, texture) than CTRL cheeses, and that Lb. rhamnosus BT68 at high concentration is related to the increase of short chain fatty acids and conjugated linoleic acid in cheese after 7 months ripening.

The mammary gland inflammation process is responsible for an increased number of somatic cells in milk, and transfers into the milk of some blood components, this causes alterations in the chemical composition and physico-chemical properties of milk. For this reason, somatic cell count (SCC) is one of the most important parameters of milk quality, therefore, European Union (EU) Regulation no 853/2004 has stated that it must not exceed the limit value of 400,000 cells/mL. The research aimed to compare chemical composition, cheese yield, and cheesemaking losses of two groups of vat milks used for Parmigiano Reggiano production, characterized by different SCC levels. During two years, ten cheesemaking trials were performed in ten different cheese factories. In each trial, two cheesemaking processes were conducted in parallel: one with low SCC milk (below 400,000 cells/mL, Low Cell Count (LCC)) and the other with high SCC milk (400,000&ndash, 1,000,000 cells/mL, High Cell Count (HCC)). For each trial, vat milk and cooked whey were analyzed, after 24 months of ripening, cheeses were weighed to calculate cheese yield. The HCC group had lower casein content (2.43 vs. 2.57 g/100 g, p &le, 0.05) and number (77.03% vs. 77.80%, 0.05), lower phosphorus (88.37 vs. 92.46 mg/100g, 0.05) and titratable acidity (3.16 vs. 3.34 &deg, SH/50 mL, 0.05) compared to LCC. However, chloride (111.88 vs. 104.12 mg/100 g, 0.05) and pH (6.77 vs. 6.71, 0.05) were higher. Fat losses during cheesemaking were higher (20.16 vs. 16.13%). After 24 months of ripening, cheese yield was 8.79% lower for HCC milk than LCC (6.74 vs. 7.39 kg/100 kg, 0.05).

The careful monitoring of cows helps minimise pain and distress during calving, moreover, knowing the exact time of birth is important to ensure timely assistance and the adequate ingestion of colostrum by the calf. However, direct visual observation is time-consuming, and the continuous presence of an observer during stage two of calving can disturb cows. Video cameras or accelerometers recording the behaviour of cows can be integrated in systems using image analysis or locomotive activity to alert the farmer as to when calving is imminent. However, alerting systems require the input of benchmark information about behaviours and changes in behaviours that can be predictive of the time of calving. Eight cows in a calving barn were continuously video-monitored. The recordings of the 24 h before delivery were analysed by instantaneous time sampling to identify the behaviours associated with an imminent birth. The same were collected in an ethogram including lying, standing, walking, turning the head towards the abdomen, eating, ruminating, drinking, sniffing the ground, allogrooming, self-grooming, and posture-changing. In our conditions, the only behaviour that was significantly influenced by the distance to delivery was posture-changing (p &lt, 0.0001). Two h before the delivery, the proportion of posture changes was different from all of the hourly proportions measured from &minus, 24 to &minus, 3 h relative to delivery (p &lt, 0.005), resulting in 3.6 times the average of the previous 22 h relative to delivery. An increase of posture changes may be an indicator of calving approaching, but further studies are needed to input benchmark values in alerting systems.

The relationship between β-lactoglobulin (β-LG) serum concentration in sows during the last 8 weeks of gestation and subsequentpiglet performance was investigated in 10 Dunel gilts. Two classes of gilts were identified with low (or high (>150 ng/ml) average serum β-LG content. For both low and high content groups, equations were calculated todescribe trends in serum β-LG content, respectively y1=10.07e0.0237x (R2=0.3122) and y2=69.00e0.0201x (R2=0.6959), wherex is the number of days of gestation. Differences in serum β-LG content between the two groups were highly significantat all weeks (P(P>0.05) between groups were shown for total number of piglets born, born alive, stillborn or mummified and piglet survivalrates up until d 21 after farrowing. The group with high serum β-LG content during gestation showed higher litterweights at d 5 (Presults indicate that serum β-LG content during the final weeks of gestation could be used as an early indicator of reproductiveefficiency, and that gilts with high content could be selected to improve herd productivity.

Aim of this research was to study the effect of somatic cell count on mineral content and salt equilibria at the level of quarter milk samples. Ten Italian Friesian cows, in which two homologous quarters (front quarters in 1 cow, rear quarters in 6 cows and both rear and front quarters in 3 cows) were characterised by a milk SCC 400,000 cells/mL (HC-milk), respectively, were selected. Cows were milked at quarter level during the morning milking and a single sample was collected from each selected quarter, thus, 26 quarter milk samples were collected. Compared to LC-milk, HC-milk was characterised by a lower content of phosphorus and potassium and by a higher content of both sodium and chloride. The equilibrium of calcium, phosphorus and magnesium between the colloidal and soluble phase of milk and the mineralisation degree of the casein micelles, were not different between HC and LC milk.

The aim of this research was to evaluate the effect of the modification of diet starch content on milk composition and onits nitrogen and mineral fractions. Ten Italian Friesian primiparous cows were randomly assigned to two groups and feda basal total mixed ration, (BSD, basal starch diet, 24.9% starch/DM) until 42 days in milking (DIM). At 43 DIM, 5 animals(control group, CTR) continued to receive the same ration and the remaining 5 cows (experimental group, EXP)were fed a low starch diet (LSD, 21.0% starch/DM) until 65 DIM, followed by a high starch diet (HSD, 28.3% starch/DM)66 to 85 DIM. From 86 DIM until 94 DIM, cows of the EXP group returned to the BSD. Milk samples were collected at 37,50, 60, 70, 80, 94 DIM. Starch intake was lower for EXP at DIM 50, 60 and higher at 70 and 80 DIM (P < 0.01). Milkyield and fat corrected milk (FCM) did not vary between groups and times of sampling, but HSD caused a significant (P< 0.05) reduction of milk fat in the EXP animals. NPN and MUN contents were affected by dietary treatments at 80 DIM(P < 0.05), being higher in CTR and lower in EXP group in comparison to their basal values (37 DIM). The αs1-caseinpercentages at 80 and 94 DIM increased in the EXP but not in the CTR group, and a marked decrease of αs2-casein percentagefor the EXP group at 94 DIM was observed (P < 0.05). Milk sodium content decreased at 80 and 94 DIM and thesodium to potassium ratio was reduced after the return to the basal diet in the EXP group (94 DIM), indicating that dietarystarch variations can be involved in the control of epithelium integrity of mammary gland in early lactation.