scholarly journals Systematic effects on activity, milk yield, milk flow rate and electrical conductivity

2002 ◽  
Vol 45 (3) ◽  
pp. 213-222 ◽  
Author(s):  
R. Firk ◽  
E. Stamer ◽  
W. Junge ◽  
J. Krieter

Abstract. The traits activity, milk yield, milk flow rate and electrical conductivity were analysed in preparation for automatic oestrus detection. Collection of data was performed on a commercial dairy farm and milking took place in a rotary milking parlour. Between February and December 1998 1,090,031 observations from 2,422 Holstein Friesian cows were accumulated. Around 30% of cows were milked thrice daily. For each trait and each cow a daily value was calculated. The fixed effects test day, parity, calving season, milking frequency, week of lactation and the random effect cow were considered in statistical analyses. With increasing number of parity, activity decreased and milk yield, milk flow rate and electrical conductivity increased. The milking frequency had significant influence on all analysed traits and for the effect calving season no consistent trend was found. All traits showed characteristic patterns during lactation. Between test days high variations were found for the trait activity. The remaining traits showed a steady level except for small fluctuations. Repeatability was 27.4% for activity and between 70 and 78.7% for the milk parameters. The repeatabilities verified the collected field data having a satisfying structure for application in automatic oestrus detection. The repeatability of the trait activity indicated high differences between and within cows. The right skewed distribution indicated the activity as a promising trait for further analyses.

2003 ◽  
Vol 46 (2) ◽  
pp. 127-142 ◽  
Author(s):  
R. Firk ◽  
E. Stamer ◽  
W. Junge ◽  
J. Krieter

Abstract. As visual oestrus detection is difficult to perform in large herds, different technical devices were developed to facilitate oestrus detection. In this investigation the significance of the traits activity, milk yield, milk flow rate and electrical conductivity due to oestrus was analysed. The traits were recorded automatically during each milking on a commercial dairy farm. Oestrus detection was performed for 862 cows on basis of time series consisting of 15 days before oestrus, the day of oestrus and 15 days after oestrus. The day of oestrus was determined by the insemination which caused a calving after 265 to 295 days. The univariate analyses of traits were performed by the time series methods day-to-day comparison, moving average, exponential smoothing and Box-Jenkins three parameter smoothing. For multivariate analyses a fuzzy logic model was developed and modified for the different combinations of traits. The efficiency of the detection models and traits was determined by the parameters sensitivity, specificity and error rate. A moving average was the best suited time series method for oestrus detection by activity data. Sensitivity ranged between 94.2 and 71% and error rate was between 53.2 and 21.5% for threshold values between 40 and 120%. The traits milk yield, milk flow rate and electrical conductivity were not suitable for univariate oestrus detection. Depending on the considered traits multivariate analyses resulted in sensitivities between 87.0 and 87.9%. The error rate varied between 28.2 and 31.0%. Further analyses should include previous information such as time since last oestrus.


2011 ◽  
Vol 28 (2) ◽  
pp. 139-146 ◽  
Author(s):  
Peter Strapák ◽  
Peter Antalík ◽  
Iveta Szencziová

Milkability evaluation of Holstein dairy cows by LactocorderThe aim of this work was to evaluate chosen milk flow characteristics of Holstein dairy cows, using mobile electronic milk flow meters - Lactocorders. A total of 181 Holstein dairy cows were evaluated and divided according to parity, lactation stage and bimodality in order to carry out a detailed comparison of measured milkability traits. The average total milk yield was 11.98±3.41 kg per milking with an average milk flow rate of 2.52±0.75 kg min-1 and a maximum milk flow rate of 3.94±1.30 kg min-1. The total milk yield showed positive correlations with the average milk flow rate (r = 0.48; P<0.001) and also with the maximum milk flow rate (r = 0.32; P<0.001). More than 47% of milk flow curves were classified as bimodal. Bimodality was positively correlated with the duration of the incline phase (r = 0.73; P<0.001) and negatively correlated with the quantity of milk obtained during the first minute of milking (r = -0.34; P<0.001). In relation to the lactation stage - the highest average milk flow rate was reached by Holstein dairy cows at the beginning of the lactation (up to 100 days in milk), and in relation to parity - the highest milk flow rates were measured in second-lactation dairy cows.


Author(s):  
Anand Mishra ◽  
Shailendra Khatri ◽  
Sanjeet Kumar Jha ◽  
Shamshad Ansari

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 384-385
Author(s):  
Oliver Fast Hinz ◽  
Pablo Chilibroste ◽  
Gabriel Menegazzi ◽  
Matías Oborsky ◽  
Pablo Soca ◽  
...  

Abstract An experiment was performed to study the effect of two contrasting defoliation intensities of a fescue based pasture on milk production of 24 mid lactating multiparous cows. The animals were blocked according to parity, body weight (587 ± 42 kg), body condition score (2.77 ± 0.16) and calving date, and were randomly allocated to one of these two treatments: lax treatment (TL) 12 cm and control treatment (TC) 6 cm, with four replications. It was used a second-year pasture of Festuca arundinacea and Lotus corniculatus (2530 ± 180 kgDM/ha), divided into eight plots of 0.3 ha. Each plot was grazed by three cows during as many days as necessary until the defoliation height of each treatment was achieved. This would be determined by daily measures of the pasture height. Animals had one grazing session from 8:00 to 16:00 h. Both treatments received 7.5 kgDM of supplementation (17% Crude Protein; 2.81 Mcal/kgDM) in individual troughs. The cows were milked twice a day (05:00 and 17:00 h). Milk production was registered daily while milk composition was measured at the beginning and at the end of the experiment (samples from two consecutive milking). For milk yield results, a mixed model was used (Glimmix procedure, SAS 9.2, 2010) to analyse with treatment, day and their interaction as fixed effects and block as a random effect. While milk composition was analysed with only treatment as fixed effect. Milk yield was greater for TL than TC, while there was no difference in milk composition between treatments (Table 1). There is a significant effect of the day and an interaction between treatment and day (Figure 1), as difference was greater for TL to the end of the grazing period. This leads to the conclusion that it is possible to improve the milk production through less defoliation intensity.


Animals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2063
Author(s):  
Marian Kuczaj ◽  
Anna Mucha ◽  
Alicja Kowalczyk ◽  
Ryszard Mordak ◽  
Ewa Czerniawska-Piątkowska

The aim of the study was to determine the effect of the number and stage of lactations, time of day and calving season of cows on milk yield from a single milking, average milking time, average milking per minute, daily milking frequency and the relationship between the tested parameters of quarter milking. The study included a herd of 65 Polish Holstein Friesian black and white cows used in a free-range barn located in south-west Poland. The animals were kept in proper welfare conditions, fed using the partly mixed ration (PMR) method on the feeding table. The milk was obtained using the Lely-Astronaut A4 Automatic Milking System (AMS). The animals on the dairy cattle farm were used in the range from the first to the seventh lactation, i.e., at the age of 2.0 to approximately 10 years. In this study, the amount of milk yielded from the hind quarters was statistically significantly higher (p < 0.05) than the trait determined for the front quarters. At the same time, the milk flow rate was statistically significantly higher (p < 0.05) in the front quarters compared to the rear quarters. The daily milk yield in right rear (RR) and left rear (LR) hind quarters was higher by 1.0 kg of milk, respectively, than in right front (RF) and left front (LF) fore quarters. The milking time of the RR and LR hind quarters during the day was longer by 104.9 and 128.8 s, respectively, than the RF and LF fore quarters. The milking speed of the RR and LR hind quarters during the day was lower by 0.2 and 1.12 g/s, respectively, than in the RF and LF fore quarters. The values of the correlation between the yields of milk and its components obtained in this study were high and positive. Correlations between the milk yield and the content of its components were negative. The obtained results confirmed that the natural physiological variability of the udder and teats structure, as well as the course of lactation, significantly affects the individual composition and milk flow during milking. The ability to regulate the milk flow by adjusting the appropriate negative pressure during the robot’s operation, in the observed variability of individual lobes of the mammary gland, increases the efficiency of milking and, as a result, reduces the risk of mastitis in cows.


1995 ◽  
Vol 62 (4) ◽  
pp. 559-566 ◽  
Author(s):  
Hans-Ulrich Pfeilsticker ◽  
Rupert M. Bruckmaier ◽  
Jürg W. Blum

SUMMARYExperiments were designed to test the hypothesis that milk ejection rate decreases during milking, thereby causing insufficient refill of the cistern and decreasing milk flow rate towards the end of milking. In a first series of experiments machine milking of the left front quarters of 11 cows was interrupted for 2 min after removal of 25, 50 or 75% of expected total milk yield, while milking was continued in the other three quarters. Milk flow was recorded during machine-on times. Intramammary pressure (IMP) was recorded during premilking teat stimulation and during interruption of milking. IMP during interruption of milking decreased with decreasing amounts of milk remaining in the udder. The IMP did not change during these interruptions when they occurred after 25 and 50% of expected total milk yield was removed. Thus, the ejection rate could keep up with the milk flow or removal rate. However, IMP increased during interruption of milking following removal of 75% of total yield, although significantly so only in cows with a high milk flow rate. Obviously, more milk was removed than was transported to the cisternal cavity. It is likely that a reduced ejection rate caused the decreased milk flow rate. In a second series of experiments the pulsation ratio of the milking machine was changed from the usual 70:30 to 50:50 with the aim of reducing the milk flow rate and thus adapting to the ejection rate at the end of milking. The changed pulsation ratio caused a reduced peak flow rate and a prolonged high milk flow period, whereas the main flow rate did not change significantly.


2017 ◽  
Vol 48 (1) ◽  
pp. 53-55
Author(s):  
Francesco Maria Tangorra ◽  
Stefania Leonardi ◽  
Valerio Bronzo ◽  
Nicola Rota ◽  
Paolo Moroni

The objective of the present study was to investigate the effect of pre-milking mechanical teat stimulation on milk yield and milking performance of dairy buffaloes in early lactation. For this purpose, twenty-two healthy Italian Mediterranean buffaloes in their first to third lactation and in early lactation (<120 days in milk) were subjected to two treatments of teat stimulation: i) washing of the teats with water for about 5 s and attaching of the milking unit within 60 s, without any pre-milking massage (farm milking routine); ii) fast pulsation (FP), achieved by increasing pulsation rate to 120 pulsations per min during the first 60 s after application of teat cups. Each treatment lasted for 10 days and the following parameters were measured: milk yield (kg/milking), milk yield at 2 min after unit attachment (kg), time between milking unit attachment and its automatic removal (min), peak milk flow rate (kg/min), and milking time to reach peak flow rate (min). The average milk flow rate (kg/min) was calculated by dividing milk yield by the actual milking time. Milk yield was not affected by mechanical pre-stimulation and during the first 2 min of milking 20.2% and 19.6% of total milk yield were milked respectively when treatments 1 and 2 were applied. The time elapsed from attachment of the milking cluster until its automatic removal was less than 8 min both for buffaloes subjected to FP, and for buffaloes subjected just to washing of the teats before attaching the milking unit. FP stimulation did not show an enhancing effect on peak and average milk flow rates and on milking time to reach peak flow rate.


1995 ◽  
Vol 62 (4) ◽  
pp. 567-575 ◽  
Author(s):  
Eddy Roets ◽  
Christian Burvenich ◽  
Jorn Hamann

SUMMARYMilk yield and milking time were measured on one occasion for several daughters (n = 6–44) from 16 bulls at morning milkings. Blood from the bulls was collected, and platelets and mononuclear leucocytes were isolated. The α2-adrenoceptors on platelet membranes were identified by binding of [3H]rauwolscine, whereas for the determination of β2-adrenoceptors on intact mononuclear leucocytes, [3H]CGP–12177 was used. It was found that mean milk flow rate was highly correlated (P < 0·001) with the α2-adrenoceptor densities on blood platelets. No correlation was found with the β2-adrenoceptors on mononuclear leucocytes. It is concluded that estimation of the α2-adrenoceptors on blood platelets from bulls could eventually be used to investigate milking characteristics of cows, and might be useful in the future as a marker in genetic studies.


2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 23-24
Author(s):  
Lindsey G Wichman ◽  
Colby A Redifer ◽  
Allison M Meyer

Abstract To determine the effect of season on perinatal nutrient availability, assessed through fetal growth, calf vigor, and neonatal circulating metabolites, multiparous and primiparous dams (age: 4.7 ± 2.4 yr; BCS: 5.3 ± 0.6) from 4 spring (2014–2017; n = 202) and 4 fall (2015, 2017–2019; n = 177) calving experiments were observed during parturition. Time to stand (spring: 67; fall: 104) was determined as minutes from birth to standing for 5 sec. After birth, calf BW and size (spring: 99; fall: 169; length, heart girth, abdominal girth, and cannon circumference) were recorded. Jugular blood samples were obtained from 63 spring and 89 fall calves at 0 (pre-suckling), 6, 12, 24, and 48 h postnatally. Data were analyzed either with the fixed effect of season (single point) or the fixed effects of season, hour, and their interaction with hour as a repeated effect (over time); calf sex was included when P &lt; 0.25. Experiment was a random effect. Fall-born calves tended to have lighter (P = 0.09) BW and faster (P = 0.05) time to stand than spring-born calves. Season did not affect (P ≥ 0.18) other calf size measures. The season x hour interaction (P ≤ 0.07) affected circulating glucose, non-esterified fatty acids (NEFA), triglycerides, urea nitrogen, globulin, and total protein. Spring-born calves had greater (P ≤ 0.009) 0 h glucose, 0 and 6 h NEFA, and 0, 6, 12, and 48 h triglycerides than fall-born calves. Fall-born calves had greater (P = 0.03) total protein at 24 h and tended to have greater (P ≤ 0.10) total protein and urea nitrogen at 48 h and globulin at 24 h. Season affected albumin, which was greater (P = 0.003) in fall-born calves. These data suggest that calving season influences perinatal nutrient availability, which may impact the transition to postnatal life.


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