Milk Flow Traits Research Articles

Machine Milkability of Dromedary Camels: Correlation between Udder Morphology and Milk Flow Traits.

Simple SummaryThe relation among udder and teat characteristics and milkability traits in dairy animals is well investigated in dairy ruminants but very little knowledge is available on camels. In this experiment, milk flow curves were recorded along with udder and teats’ measurements for 32 dairy camels. This study revealed that machine milked camels had well developed teats and udders with large variability in size and shape. Daily milk yield, peak and average milk flow rates were highly and positively correlated with teat diameter and udder depth. However, selection scheme based on dairy potential only could lead to aversive udder drive and significant degradation of the external morphology of the udder. Thus, our study gave first elements for morphological selection based on machine milking characteristics.This study aims to measure mammary morphological traits with a functional influence on machine milking ability of Tunisian Camels (Camelus dromedarius) and their evolution according to the stage of lactation and parity. Udder and teat measurements were recorded before morning milking and associated with the measurement of milk emission kinetics parameters evaluated with Lactocorder® devices (WMB AG, Balgache, Switzerland) and observations. Three main teat shapes were recorded and their dimensions evolved with parity and stage of lactation. The milk flow curves were classified into three main types according to their maximum and average flow rates and they also evolve according to parity and stage of lactation. An average of 41% of the milk flow curves was bimodal. The correlations showed that some morphological traits were unfavorable to rapid milking and that these increase with parity. Therefore, this study provides the first elements for a morphological selection associated with an aptitude for mechanical milking which appears rather good in our dromedaries. Nevertheless, it will be necessary to monitor a possible negative evolution of the functional and anatomical traits of the udders during the career of the animals.

Can Milk Flow Traits Act as Biomarkers of Lameness in Dairy Cows?

We hypothesized that lameness has an impact on milk flow traits. The aim of the current study was therefore to investigate the relation between lameness and milk flow traits in dairy cows. For this study 73 healthy and 55 cows with lameness were selected. Lameness was diagnosed by a local specialized veterinarian, according to the standard procedure. The blood samples were collected during clinical examination. The milking properties of cows were evaluated twice in a row—during evening and morning milking. The selected cows in the current lactation did not receive veterinary treatment, and correct hoof trimming was not performed at least four weeks before the experiment. The measurements were taken by two electronic mobile milk flow meters (Lactocorder®®, WMB AG, Balgache, Switzerland). Milk flow data were processed using LactoPro 5.2.0 software (Biomelktechnik Swiss). Cortisol concentration was measured with the automated analyzer TOSOH®® AIA-360 (South San Francisco, CA, USA). We found out that milk flow traits can act as biomarkers of lameness in dairy cows. We determined that the milk yield in the first minute of healthy dairy cows was 1.77 kg higher than that of lame cows. The electrical conductivity during the initial time of milking of healthy cows was 0.24 mS/cm lower than that of the lame group. The milking duration of LA cows was 1.07 min shorter and the time of incline in milk flow from 0.5 kg/min till the reach of the plateau phase was longer. The risk of lameness was most clearly indicated by an increase in blood cortisol concentration; if its blood level in cows exceeds 1 µg/dL, the risk of identifying lameness increases 4.9 times.

Evaluation of automatic milking system variables in dairy cows with different levels of lactation stage and reproduction status.

In this study, we hypothesized that differences of automatic milking systems (AMS) variables in dairy cows during estrus and through diverse stages of lactation can be suggested as alternative indicators to support the pregnancy in dairy farms using automatic milking systems. The key objectives were: (1) to determine the variation of automatic milking system indicators during lactation and to estimate the relationship with reproduction status in dairy cows; (2) to test the hypothesis that milking traits of cows can be influenced by estrus and conceiving, and can be used as a predictor of the likelihood of reproductive success in dairy herds. Estrus synchronization was performed in 368 healthy Lithuanian Black and White cows. All cows (n = 368) were synchronized and inseminated for the first time on the 91st day in milk (DIM). Cows not pregnant (17.39%) were synchronized and inseminated again at 132 DIM. After the first insemination pregnant (n = 304) cows were identified as group 1, after the second insemination pregnant (n = 58) cows - as group 2. Overall, 12 01 713 records of udder quarters in cows from 5 to 305 DIM were evaluated. The results revealed the reduction in milk yield during estrus 11.05% on 91 DIM and 13.89% on 132 DIM (P < 0.001) and an increment in milk flow traits in cows after 91 DIM (P < 0.05), also a slight decline in milk flow traits on 132 DIM. Furthermore, milking frequency (MF) of cows decreased significantly (P < 0.001) after conceiving. The interval between milkings (MI) increased (40.30%) during estrus of cows in group 1 (P < 0.001), and thereafter gradually increased, however in group 2 there was a temporary increment (6.06%) on the 91 DIM and steady rise (42.13%) on 132 DIM was noticed. The results highlight that changes in AMS indicators of cows may be considered as an additional tool for improvement of reproductive management in dairy herds, but further research-based studies are necessary before practical application.

Factors affecting milking speed in Murciano-Granadina breed goats.

Milk flow during the first minute of milking was analyzed using data from 1,132 Murciano-Granadina breed goats belonging to 17 herds. During the individual lactations, 2 test days were scheduled for recording several milk flow traits, total milk, milk composition (fat and protein percentages), and somatic cell count. Average lag time from teatcup attachment to arrival of milk at the milk claw (T0) was 4.9 s and at the milk meter (T1) was 15.8 s. Average milk flow after 30 s (MF0.5) was 0.29kg/30 s (0 to 1.1kg/30 s) and milk flow at 60 s or milking speed (MF1) was 0.67kg/min (0.1 to 2.1kg/min). Repeatabilities of T0, T1, MF0.5, and MF1 were 0.45, 0.58, 0.62, and 0.68, respectively. The MF1 showed high phenotypic correlation withT1(-0.63) and MF0.5 (0.90), medium values withT0(-0.42) and total milk (0.22), and very low values (-0.04 to -0.12) with fat, protein, and somatic cell count. We found no differences between flows during the first 3 lactations, with a reduction as the lactation number increased. Months in milk since parturition affected MF1, being highest in the first 3mo (0.67-0.71kg/min) and decreasing until the end of lactation (0.58kg/min). The effect of herd-test day was significant for all traits. Inclusion of all these effects for the analysis of milk flow traits is considered necessary.

Effects of manual udder stimulation on milk partitioning and flow traits during the machine milking in dairy camels (Camelus dromedarius)

A total of 9 multiparous dromedary camels in late stage of lactation (287±8 DIM; 3.8±0.8 kg/d) were used to study the effect of manual udder stimulation on machine milking efficiency of dairy camels under intensive management condition. Experimental design consisted of 3x3 Latin square with 9 animals allocated randomly and equally to 3 treatment (T1=60 s, T2=90 s and T3=120 s). All camels were machine milked twice daily. Milk yield and milk flow parameters were recorded by Lactocorder® milk meters. Udder health was evaluated by California mastitis test (CMT) and somatic cell counts (SCC). Cisternal milk was determined 14 h after milking using Atosiban®. Volumes of machine milk (MM), machine stripping milk (MSM) and residual milk (RM) were recorded in duplicate. No subclinical mastitis was detected during the experimental period as indicated by the CMT ( 25%). The increase of udder stimulation from T1 to T3 decreased (p<0.05) the lag time (LT) (3.83 to 2.24 sec) in camels of G1 and the MSM (26.6 to 14.8%) as well as RM (46.1 to 31.4%) in camels of G2. Bimodal curves tended (P=0.08) to decrease from 43.6% to 28.1% when duration of udder stimulation increased from T1 to T3 in camels of G2. In conclusion, increase duration of manual udder stimulation to 90–120 s ameliorate the machine milking efficiency in harder milked camels at late stage of lactation. (Resume d'auteur)

Effects of vacuum level and pulsation rate on milk ejection and milk flow traits in Tunisian dairy camels (Camelus dromedarius).

This work aims to compare the effects of milking at two vacuum levels (38 and 48 kPa) and three pulsation rates (60, 90, and 120 cpm) on milk production and milk flow characteristics. Six multiparous Maghrebi camels in late lactation and once daily milked were used. The best combination of setting for camel's milking was high vacuum and low pulsation rate (48 kPa/60 cpm). Milk yield and average and peak milk flow rate were the highest, while milking time was the shortest using this combination of setting (3.05 ± 0.30 kg, 1.52 ± 0.21 kg/min, 2.52 ± 0.21 kg/min, and 3.32 ± 0.31 min, respectively). Lower vacuum level lengthened milking time by more than 100 % and was not sufficient to extract milk correctly (1.69 to 2.48 times less milk yield harvested), suggesting a negative interaction with the stimulatory effect of pulsation. Higher pulsation rates did not better stimulate the camels and induced more bimodality and lower milk flow rates. Animal characteristics and liner/claw design affect machine milking and further investigations must be carried out to verify their effects and to study long-term effect of high vacuum level on udder health and teat condition.

First description of milk flow traits in Tunisian dairy dromedary camels under an intensive farming system

In order to evaluate milking ability in dromedary camels, 124 milk flow curves were registered during morning milking of 20 dairy Maghrebi dromedary camels. Animals were in lactations 1-8, were 6-19 years old and were 4-15 months of their current lactation. Milk flow curves were recorded using an electronic milk flow meter (Lactocorder®). Milk flow curves were classified in three typical patterns: type 1 represents curves with one high and short peak of milk flow; type 2 represents curves with a moderate mean milk flow rate during a large plateau phase; and type 3 represents curves with lower mean milk flow rate and a relatively longer milking duration. The ratio of the different milk flow patterns in the population evaluated was 40:38:22% for types 1, 2 and 3, respectively. The highest milk yield per milking, average and peak milk flow were observed in camels with type 1 curves (4·24kg, 1·49 and 3·54kg/min, respectively) followed by type 2 animals (3·30kg, 1·12 and 2·12kg/min, respectively) and lastly type 3 curves (2·34kg, 0·65 and 1·23kg/min, respectively). This study confirmed that a major proportion of dromedary camels have a suitable machine milking ability. Nevertheless, our results suggest that pre-stimulation and improving the milking process may improve milking efficiency and guarantee a more complete and rapid emptying of the udder.

Estimates of marker effects for measures of milk flow in the Italian brown Swiss dairy cattle population

BackgroundMilkability is a complex trait that is characterized by milk flow traits including average milk flow rate, maximum milk flow rate and total milking time. Milkability has long been recognized as an economically important trait that can be improved through selection. By improving milkability, management costs of milking decrease through reduced labor and improved efficiency of the automatic milking system, which has been identified as an important factor affecting net profit. The objective of this study was to identify markers associated with electronically measured milk flow traits, in the Italian Brown Swiss population that could potentially improve selection based on genomic predictions.ResultsSires (n = 1351) of cows with milk flow information were genotyped for 33,074 single nucleotide polymorphism (SNP) markers distributed across 29 Bos taurus autosomes (BTA). Among the six milk flow traits collected, ascending time, time of plateau, descending time, total milking time, maximum milk flow and average milk flow, there were 6,929 (time of plateau) to 14,585 (maximum milk flow) significant SNP markers identified for each trait across all BTA. Unique regions were found for each of the 6 traits providing evidence that each individual milk flow trait offers distinct genetic information about milk flow. This study was also successful in identifying functional processes and genes associated with SNPs that influences milk flow.ConclusionsIn addition to verifying the presence of previously identified milking speed quantitative trait loci (QTL) within the Italian Brown Swiss population, this study revealed a number of genomic regions associated with milk flow traits that have never been reported as milking speed QTL. While several of these regions were not associated with a known gene or QTL, a number of regions were associated with QTL that have been formerly reported as regions associated with somatic cell count, somatic cell score and udder morphometrics. This provides further evidence of the complexity of milk flow traits and the underlying relationship it has with other economically important traits for dairy cattle. Improved understanding of the overall milking pattern will aid in identification of cows with lower management costs and improved udder health.

Effectiveness of genomic prediction on milk flow traits in dairy cattle

BackgroundMilkability, primarily evaluated by measurements of milking speed and time, has an economic impact in milk production of dairy cattle. Recently the Italian Brown Swiss Breeders Association has included milking speed in genetic evaluations. The main objective of this study was to investigate the possibility of implementing genomic selection for milk flow traits in the Italian Brown Swiss population and thereby evaluate the potential of genomic selection for novel traits in medium-sized populations. Predicted breeding values and reliabilities based on genomic information were compared with those obtained from traditional breeding values.MethodsMilk flow measures for total milking time, ascending time, time of plateau, descending time, average milk flow and maximum milk flow were collected on 37 213 Italian Brown Swiss cows. Breeding values for genotyped sires (n = 1351) were obtained from standard BLUP and genome-enhanced breeding value techniques utilizing two-stage and single-step methods. Reliabilities from a validation dataset were estimated and used to compare accuracies obtained from parental averages with genome-enhanced predictions.ResultsGenome-enhanced breeding values evaluated using two-stage methods had similar reliabilities with values ranging from 0.34 to 0.49 for the different traits. Across two-stage methods, the average increase in reliability from parental average was approximately 0.17 for all traits, with the exception of descending time, for which reliability increased to 0.11. Combining genomic and pedigree information in a single-step produced the largest increases in reliability over parent averages: 0.20, 0.24, 0.21, 0.14, 0.20 and 0.21 for total milking time, ascending time, time of plateau, descending time, average milk flow and maximum milk flow, respectively.ConclusionsUsing genomic models increased the accuracy of prediction compared to traditional BLUP methods. Our results show that, among the methods used to predict genome-enhanced breeding values, the single-step method was the most successful at increasing the reliability for most traits. The single-step method takes advantage of all the data available, including phenotypes from non-genotyped animals, and can easily be incorporated into current breeding evaluations.

Effect of vacuum level on milk flow traits in Mediterranean Italian buffalo cow

The aim of this study was to determine the effects of six different working vacuum levels (range 37–52 kPa) on the milk production, milk flow rate and milking times of Mediterranean Italian buffalo. A total of 801 milk flow curves of 450 animals of different parity and at different stages of lactation were recorded at random by electronic milk flow meters (Lactocorder®) over a period of 12 weeks. The vacuum level did not significantly affect the individual milk production per milking (average 4.02±0.06 kg). Lower vacuum level resulted in a decrease in average and peak flow rate (P<0.001), and an increase in effective milking time between attaching the teat cup and reaching the value of 0.20 kg/min at the end of milking (P<0.001). Vacuum levels of 37 and 40 kPa provided good milkability conditions, in which the plateau phase was longer than the decline phase while lag time was not affected by vacuum level.

Comparison of the effects of quarter-individual and conventional milking systems on milkability traits

Abstract. This study was carried out to investigate a new quarter-individual milking system called MultiLactor® (Siliconform GmbH, Türkheim, Germany). The MultiLactor enables milking on quarter level basis with low vacuum (37 kPa), sequential pulsation and periodic air inlet. Within the same dairy farm, the influence of this quarter-individual milking system (MULTI) on milkability traits was compared with a conventional milking system (CON). CON was equipped with a conventional milking cluster and used alternating pulsation. Vacuum level was adjusted to 40 kPa. For the study, 84 Holstein Friesian cows were randomly selected and uniformly divided into two herds. During the 30-week survey, the milk flow curves were recorded every other week by using a LactoCorder (WMB, Balgach, Switzerland). Significant differences (P&lt;0.05) between both milking systems were found for all milk flow traits, except for milk yield and decline phase. Concerning the incline (tAN) and plateau (tPL) phase, large differences existed between MULTI and CON. The estimated value of tAN calculated for MULTI (29.4 s) took only half of the time when calculated for CON (56.4 s). The estimated value of tPL at CON was reduced by 1.43 min (35 %) compared to MULTI. Milking process at MULTI (8.49 min) took longer time than for CON (7.43 min). From the study, it was concluded that the effect of shorter tAN in the quarter-individual milked cows may be related to additional prestimulation by an actuator. In contrast, the longer milking time in MULTI is possibly caused by lower vacuum level and periodic air inlet.

Bimodality and the genetics of milk flow traits in the Italian Holstein-Friesian breed

The overall goal of this study was to investigate milk flow traits in Italian Holstein-Friesian cows and, in particular, the bimodality of milk flow, defined as delayed milk ejection at the start of milking. Using a milkometer, 2,886 records were collected from 133 herds in northern Italy from 2001 to 2007. All records included 5 time-period measurements for milk flow, somatic cell score (SCS), milk yield, 8 udder type traits, and the presence or absence of bimodality in milk flow. Genetic parameters were estimated using linear animal models for continuous traits such as milk flow, udder type, SCS, and milk production, whereas bimodality was analyzed as a categorical trait. With the exception of decreasing time (which had a very small heritability value of 0.06), heritability values for milk flow traits were moderate, ranging from 0.10 (ascending time) to 0.41 (maximum milk flow). In addition, moderate to high genetic correlations were estimated between total milking time and other time measures (from 0.78 to 0.87), and among time flow traits (from 0.62 to 0.91). The decreasing time was the trait most genetically correlated with udder type traits, with correlation values of 0.92 with rear udder height, 0.85 with rear udder width, and 0.73 with teat placement. Large udders with strong attachments were also associated with greater milk production. Heritability estimated for bimodality was 0.43, and its genetic correlation with milk flow traits and SCS indicated a sizable genetic component underlying this trait. Bimodality was negatively associated with milk production; shorter milking times and greater peak milk levels were genetically correlated with more frequent bimodal flows, indicating that faster milk release would result in an increase in bimodal patterns. The negative genetic correlation of bimodality with SCS (−0.30) and the genetic correlation between milk flow traits and SCS suggest that the relationship between milkability and SCS is probably nonlinear and that intermediate flow rates are optimal with respect to mastitis susceptibility. Quicker milk flow over a shorter period would increase the frequency of bimodal curves in milking, whereas the correlation between bimodality and both ascending and descending time was less clear.

Milk emission and udder health status in primiparous dairy cows during lactation

To investigate the relationships between milk flow traits and udder health status in primiparous cows, 74 primiparous Holstein cows were randomly selected in 5 herds and monitored monthly throughout the whole lactation. A total of 2902 quarter milk samples were collected for bacteriological analyses and the determination of lysozyme, N-acetyl-beta-glucosaminidase (NAGase) and somatic cell count (SCC). Milk flow curves of the whole udder of each cow were registered with continuous electronic milk flow meters. Teat conditions and teat thickness changes during milking were assessed monthly. Quarters, udders and cows were classified as healthy, latent, inflamed and subclinical depending on SCC and the results of bacteriological analyses. Lysozyme in milk, teat apex score and teat thickness change did not vary with udder health status while NAGase in milk significantly increased as udder health status worsened (P<0.001). Milk production (P<0.001) and time of plateau phase (P<0.05) were significantly lower in subclinical cows in comparison with the others. Animals with a high frequency of bimodal curves in the first 100 days in milk showed the worst udder health status during the whole lactation (P<0.01). Moreover, cows classified as subclinical in the first 3 months of lactation had higher peak milk flow than healthy cows (3.81 v. 3.48 kg/min; P<0.05) and shorter duration of plateau phase, expressed both as minutes and as percentage of time of milk flow (pTPL; P<0.001). Multivariate logistic analysis showed udder health status to be associated with duration of plateau phase, time of milk flow, bimodality and duration of overmilking phase. With short time of plateau phase (pTPL <25%), short time of milk flow (<5 min), presence of bimodality and long overmilking phase (>0.8 min) there was an increased risk of poor udder health status. These milk flow traits can be predictive indicators of udder health status; time of plateau phase, expressed as percentage of time of milk flow, can also be a useful parameter for animal selection.

Effect of liner characteristics on teat apex condition and milk flow traits

Milking machine characteristics, as liner type, can influence milk flow trait and teat apex condition. The aim of the study was to investigate the effects of liner type on milk flow traits and teat apex condition. In addition, the age of the liner was taken into account. Four commercial farms were visited three times in order to monitor milk flow traits and teat apex condition. Electronic milk flow meters were used. Teat apex condition was assessed following Teat Club International guidelines. Results of the multiple correspondence analysis showed that the farms with triangular liner, percentage of teats rough and very rough less than 20% of the total teats and overmilking less than 0.5min were clustered in the same space and showed a positive correlation. In contrast, they had a negative correlation with farms having higher percentages of teats with hyperkeratosis, longer overmilking phase and with farms using round liners.

Milk flow pattern, somatic cell count and teat apex score in primiparous dairy cows at the beginning of lactation

The aim of the study was to investigate the relationships between milk flow traits, milk Somatic Cell Count (SCC) and teat apex score in primiparous cows during the first 120 days of lactation. A total of 82 primiparous Holstein cows were randomly selected in 6 herds characterized by different milking machines and management. The cows were monitored monthly during the first 120 days of lactation. Each month, milk flow curves of the whole udder of each primiparous cow were registered with continuous electronic milk flow meters (Lactocorder), quarter milk samples were aseptically collected, somatic cells were counted, and teat apex scores were assessed. Quarter milk samples were divided in two groups according to SCC: <200,000 and >200,000 cells/ml, respectively. At udder level each cow was classified as low SCC (LSCC) when all quarters had <200,000 cells/ml and high SCC (HSCC) in all other situations, separately for each control. Animals with at least one HSCC control during the first 120 days of lactation (n=33), compared to subjects always classified as LSCC cows (n=49), showed significantly higher average milk flow (2.32 vs 2.13 kg/min; P<0.05), peak milk flow (3.71 vs 3.14 kg/min; P<0.05), lower duration of plateau phase (2.33 vs 3.27 min; P<0.05), longer duration of increase phase (0.81 vs 0.66 min; P<0.05), and higher average SCC (4.07 vs 3.45 Log10 SCC; P<0.05). Moreover, primiparous cows with at least one HSCC control had a significant increase in peak milk flow during the first four months of lactation, while the other cows showed only a slight increase. Teat apex scores significantly increased in both groups of primiparous cows as lactation progressed but values in subjects always classified as LSCC animals were constantly lower with respect to cows with at least one HSCC control. The results obtained in this study support the relationship between SCC, teat apex score and milk flow traits.

Factors Affecting Milk Flow Traits in Dairy Cows: Results of a Field Study

The study of milk flow curves provides useful information for enhancing milking efficiency and protecting udder health by adapting milking machine and milking procedures to the physiological requirements of the cow. The aim of this experiment was to investigate, using field data, the relationships among traits of the milk flow curves, their sources of variation, and milking performances in terms of milk production, machine-on time, and udder health. A total of 2,486 milk flow curves of the whole udder were collected in 82 Italian Holstein-Friesian dairy herds in the Lombardy region of Italy. Approximately one-third (35.1%) of milk flow curves were classified as bimodal. Most flow characteristics were influenced by lactation number, days in milk, and peak flow but also strongly affected by premilking operations. Proper udder preparation, including forestripping and predipping, resulted in better milking performances compared with poor preparation, with greater milk yield per milking, shorter milking time, and lesser bimodality. Premilking delay time, between the start of teat stimulation and cup attachment, affected milking time significantly: The shortest milking time was obtained for a range of delay time between 1 and 60s. As the delay time increased, the percentage of bimodality dropped significantly. Increasing the number of clusters per operator led to greater percentages of bimodal curves. The greater somatic cell count of cows with bimodal curves supports the hypothesis of the negative effect of bimodality on udder health and indicates the importance of avoiding its occurrence using proper pre-milking procedures.

Milking procedures and milk ejection in Italian Brown cows

The aim of the study was to describe, on the basis of field data, the traits of milk flow curves of Italian Brown cows and to investigate some sources of variation. A total of 1,450 milk flow curves of the whole udder were collected in 81 Italian Brown dairy herds in Lombardy, Italy, using electronic mobile milk flow meters. Parity order and days in milk affected most milk flow traits. Milk flow curves showed some defects dependent on milking management practices: very long machine-on time, long duration of overmilking phase, high percentage of stripping and moderate percentage of bimodality.

Milk flow traits in Mediterranean Italian Buffaloes

The aim of this study was to analyze the milk flow pattern in Italian Mediterranean Buffaloes in relation to parity and oxytocin administration. A total of 330 milk flow recorders were collected during morning and evening milkings by using an electronic milk flow meters (Lactocorder®). Milk flow curves were examined and subject were divided according milk flow pattern in: normal pattern, bimodal pattern and “double pattern”. Data were analysed by using ANOVA and Chi square test. Total milk yield per milking was significantly higher (P<0.01) in pluriparous and consistent with the average DIM of 205 days. No differences in milk yield and maximum milk flow were found between the oxytocin groups while both parameters were higher in bimodal and double pattern groups compared to normal milk flow pattern. Lag time was higher (P<0.01) in oxytocin treated group and in normal vs the other two pattern groups. Length of main milking phase was higher in pluriparous, oxytocin treated group (P<0.01) and in bimodal vs the normal one (P<0.05) while double pattern showed the highest value (P<0.01). Percentage of bimodal milk flow was 13.7% while a double flow pattern was 12.4%. A higher percentage of double pattern was found in oxytocin treated buffaloes vs normal and bimodal ones (18.1% vs 8.1% and 7.5% respectively; P< 0.05) and in pluriparous vs primiparous (74.4% vs 25.6%; P< 0.05).

Milk flow traits of buffalo cows in intensive farming system

The particular morphology of buffalo udder is associated to milking difficulties. To better understand the characteristics of milk ejection in buffaloes, a study was conducted in an intensive farm in Lombardy, Italy. A total of 184 milk flow profiles were measured with an electronic flow meter. The results showed that during the first 3 minutes of milking 73% of total milk yield was milked; lag time of milk ejection (1.94 min ± 1.57) was very long and increased significantly with the increasing of lactation stage. The overmilking phase has also a long duration (33% of total milking time, on average). Administration of oxytocin before milking did not significantly affect milk flow parameters and machine on-time. The results suggested that proper pre-milking stimulation and prompt cluster takeoff could improve milking efficiency, ensuring good milk letdown and protecting teat conditions.

Quarter milk flow patterns in dairy cows: factors involved and repeatability

The objectives of our study were to describe the variation of quarter milk flow parameters and to determine the factors that affect these parameters the most. Additionally, repeatabilities (r&lt;sub&gt;2&lt;/sub&gt;) of the quarter milk flow traits (duration of milk flow, time to reach peak flow, peak flow rate, and duration of milk flow in single phases &amp;ndash; increase, plateau, decline and blind phase) were calculated. Repeatability of total milk yield and milk yield in single phases was calculated, too. The data from 39 Holstein cows, in their first to third lactation and free of clinical mastitis, were used for statistical analysis. A total of 1 656 curves of quarter milk flows were recorded during six consecutive days. At the last evening and morning milking samples of milk from each quarter were collected for determination of somatic cell count (SCC). Peak flow rate, quarter position, time of milking (morning and evening) and SCC significantly affected most of the measured traits. The highest r2 were for total milk yield and yield of plateau phase 0.53 and 0.50, resp. The lowest r2 were calculated for the duration of increase phase, and milk yield of the increase and blind phase 0.26, 0.12 and 0.21, resp. Peak flow rate, SCC, time of milking and front-rear position influenced the values of r2 of traits to various extent.