Changes of fat-to-protein ratio from start to the mid-lactation and the impact on milk yield

Abstract

The aim of the study was to evaluate the changes of fat-to-protein ratio (F/P ratio) from early to mid-lactation and the impact on milk yield. 208 Holstein cows from 3 dairy farms in west Slovakia calved between years 2012 and 2015 were observed. Into the study 908 test-day records of milk yield were included. Cows were from 5 to 150 days in milk (DIM). Statistical analysis and analysis of influence of F/P ratio on milk yield were performed by SAS. The sample of observed cows produced 35.25 ± 11.55 kg*day -1 of milk. The average day in milk was 77.40 ± 41.17 and the average F/P ratio was 1.19 ± 0.25. In acidosis risk were 19.71% of all observation and 8.92% were in ketosis risk. The occurrence of acidosis risk increased and the occurrence of ketosis risk decreased from early to mid-lactation. The model described the variation of milk yield by 44.20%. All of the selected effects except the year of calving had high statistical significant (P<0.01) influence to variation of milk yield. The effect of F/P ratio decreased the milk yield by 4.97 kg*day -1. The highest impact of F/P ratio was observed between 5 and 30 DIM and decreased the milk yield by 6.31 kg*day -1 . The average F/P ratio of observations between 5 and 30 DIM was 1.32 ± 0.30. The smallest impact of F/P ratio was found between 61 and 90 DIM and decreased the milk yield by 3.74 kg*day -1 . The average F/P ratio of observation between 61 and 90 DIM was 1.16 ± 0.22. It is possible to use F/P ratio as non-invasive indicator of metabolic status to decrease the negative impact to milk yield. . Priemerná hodnota pomeru tuku a bielkovín medzi 61 až 90 dňom laktácie bola 1,16 ± 0,22. Pomer tuku a bielkovín je možné použiť ako neinvazívny ukazovateľ na zníženie negatívneho dopadu metabolického stavu na mliekovú úžitkovosť.Kľúčové slová: pomer tuku a bielkovín, holštajnské kravy, metabolická porucha, kontrolný deň

Effects of Breed and Stage of Lactation on Milk Fatty Acid Composition of Italian Goat Breeds

“…The average F/P and its range were in agreement with other studies on goat milk [30,58]. The average F/P, which is an indicator of the metabolic status of the animal, was quite constant during lactation, suggesting the absence of metabolic disorders during the study [59].…”

Genetic and nongenetic factors affecting on-farm performance of peri-urban dairy cattle in west Africa

“…Although, feeding of high amounts of grains is uncommon in peri-urban dairy farms in Ouagadougou [E. Schlecht, J. Plagemann (University of Kassel and University of Goettingen), S. E. Mpouam, H. O. Sanon (Institut de l'Environnement et de Recherches Agricoles, Ouagadougou, Burkina Faso), M. Sangaré (Centre International de Recherche-Développement sur l'Elevage en zone Subhumide, Bob-Dioulasso, Burkina Faso), and R. Roessler, unpublished data], the prevalence of acidosis in our study, as indicated by a F/P quotient of <1.0, was unexpectedly high (19.7%) and comparable to values obtained for Holstein cows in Croatia (Gantner et al, 2016). We noted a declining trend in the course of the lactation, which contradicts other studies (Gantner et al, 2016;Vlček et al, 2016) where prevalence rates of acidosis have been increasing; however, those studies only assessed the prevalence rate up to the fifth lactation month. In summary, systematic studies are needed that compare different methods using a larger number of dairy cows to prove the suitability of the F/P ratio in local and crossbred cattle genotypes in tropical dairy production systems, and to define genotype-specific threshold values of the F/P quotient to determine the risk of ketosis and also acidosis in these systems.…”

“…The prevalence rate in their study was much lower (36.7%) than the prevalence rate in our study; however, those authors used ketone bodies in urine, milk, and blood as indicators, making a comparison with our results difficult. Comparing our results with studies that have used the F/P ratio for cows in Italy (33%; Toni et al, 2011) and Slovakia (12%; Vlček et al, 2016), the prevalence rate obtained in our study is still extremely high. Previous studies revealed environmental differences in the prevalence rate of ketosis.…”

Biomarkers of fitness and welfare in dairy cattle: healthy productivity

“…(2015) also described that RA or SARA do not affect milk protein content, but do reduce fat content in milk compared to control cows (4.14 and 5.08%, respectively). Therefore, animals with fat:protein ratio below 1 in milk are susceptible to suffer RA or SARA (Danscher et al ., 2015; Vlček et al ., 2016; Rojo-Gimeno et al ., 2018).…”