Diet change from a system combining total mixed ration and pasture to confinement system (total mixed ration) on milk production and composition, blood biochemistry and behavior of dairy cows

Abstract

This study aimed to determine if a diet change from a mixed system to a confinement system affects the milk production and composition, behavior and blood biochemistry of dairy cows. Cows were assigned randomly to one of the two treatments: cows fed with TMR (total‐mixed‐ration) (confined) throughout the period group fed TMR (GTMR, n = 15) and cows that changed their diet from pasture plus TMR to exclusive TMR at 70 ± 14 DIM (GCHD, n = 15). GTMR cows produced more milk and greater lactose and protein yield before the change of diet than GCHD cows (p ≤ .01), but these differences disappeared after the change. GCHD cows decreased the frequency of rumination and lying from before to after the change (p ≤ .03), but in GTMR cows no changes were observed. After diet change, GCHD cows had lower frequency of rumination and lying than GTMR cows (p ≤ .02). Before the change, GCHD cows had greater NEFA (non esterified fatty acids) concentrations than GTMR cows (p = .002). Abrupt change from a mixed system to a confined system was favorable on blood biochemical and milk variables of dairy cows. However, in relation to behavior, the cows expressed difficulties to adapt quickly to the abrupt change of system.

Growth of foetal bones and metabolic profile during gestation in primiparous ewes and multiparous ewes

“…The lower detection limits of these kits were 4.6 mg/ml, 1.1 mg/ml, 0.2 mg/dl, 0.016 mmol/L and 0.01 mmol/L for total proteins, albumin, glucose, B‐hydroxybutyrate and NEFAs, respectively. The inter‐assay and intra‐assay coefficient of variation for all controls was below 10% (Grille, Adrien, Olmos, Chilibroste, & Damián, 2019). The concentration of globulins (constituted by immunoglobulins and other proteins such as enzymes or carrier proteins) was estimated by the difference between total proteins and albumin (Tothova, Nagy, & Kovac, 2016).…”

Milk Fatty Acid Profile of Holstein Cows When Changed from a Mixed System to a Confinement System or Mixed System with Overnight Grazing

“…Diet change in GCHD and GTMR+P was carried out on November 16th, according to historical records of THI values in the region [34], which corresponds to 70 ± 14 days in milk (DIM). The TMR was offered from 11:00 to 15:00 H in open stalls for all treatments, and cows had free access to water.…”

“…Feeders covered (70 m × 3 m) with concrete floor and metal roof and an area with dirt floor without roof but with shade in each treatment (50 m × 4 m). All treatments were in the same environment and confinement system but in different and adjacent pens, as described by Grille et al [34]. The drinking troughs were plastic made (3:76 m × 0:76 m × 0:44 m).…”

“…In such systems, cows are exposed to extreme weather conditions (such as heat stress); notwithstanding, ~63% of dairy farms have access to water near the milking parlor or the paddocks, and although 75% of the farms have natural shade [33], it is usually located on cow trails and not in the paddock or resting areas. In this sense, confinement systems are used to mitigate climatic conditions in summer and minimize its negative effects on milk yield [34,35], provide independence from forage availability fluctuation [36,37], and increase total dry matter (DMI) and energy intake per cow to achieve better productive levels [38,39]. However, beyond the productive advantages provided by confinement systems, the lack of pasture in diet would negatively affect milk fat composition [25,28,40,41], animal welfare [42], and consumer perception of dairy products [20,43].…”

“…Hence, during summer, an alternative mixed system consisting of one grazing session at night would improve milk fat composition, while at the same time reducing heat stress negative effects. In addition, although the change from a mixed system to one in confinement in summer improves milk production and biochemical profile in blood, from behavioral point of view, cows fail to adapt in the short term to the lack of pasture, affecting their animal welfare [34]. Although the effect of dietary change on milk FAP when cows switch from pasture to TMR (and vice versa) has been evaluated, to our knowledge, the consequences of changing to a mixed system with one overnight grazing in summer on milk FAP have not been studied.…”