Effect of feeding total mixed ration supplemented with sodium bicarbonate and magnesium oxide on milk yield, milk composition and manure score in early lactating dairy cattle

The study was conducted on 120 crossbred early lactating dairy cows to compare the effect of feeding Total Mixed Ration (TMR) supplemented with or without buffers i.e. sodium bicarbonate (NaHCO3) and magnesium oxide (MgO) on milk yield, milk composition (milk fat percentage, solid not fat) and manure score. Animals were selected from 8 dairy farms in the Hoshiarpur district during the July-August period of 2021 and 2022, they were divided into 3 treatment groups (T1, T2 and T3) at each farm with 5 cows in each group, and 8 replications. During the 60 days trial, each cow in the treatment group T3 was fed a diet consisting of TMR along with a buffer prepared on farm using NaHCO3 and MgO in the ratio of 3:1 and mixed in concentrate ration @ 1kg/quintal. Each cow in group T2 was fed a diet that contained only TMR. In T1group, no TMR and buffers were fed to the cows, only routinely farmers practiced was followed. The TMR was offered ad libitum indoors in T2 and T3 treatment groups at 09:00 and 18:00 h. Milk yield, milk fat percentage, Solid Not Fat (SNF) and manure score were recorded on days 0 and 60 of the 60-day trial. SPSS software was used for statistical data analysis. The results showed that feeding TMR to early lactating dairy cows with or without the addition of dietary NaHCO3 and MgO increased milk yield, milk fat percentage and SNF concentration significantly (p>0.05). However, there was no significant (p>0.05) difference in milk yield between the T2 and T3 treatment groups. Additionally, cow dung was observed using the consistency and digestion methods. Score 2 was noted in T1 treatment group, whereas Score 3 was noted in the T2 and T3 treatment groups under the consistency method. Using the digestion method, Score 2 was seen in the T1 treatment group, whereas Score 1 was seen in the T2 and T3 treatment groups. Implementing TMR in dairy cattle is efficient and effective, particularly in terms of milk production and milk composition, as well as improving manure score, which is an indicator of feed digestibility.