Effects of dietary microbial feed supplement on production efficacy in lactating dairy cows

Dietary supplementation of rumen native microbes improves lactation performance and feed efficiency in dairy cows

Objectives were to determine the effects of 2 dietary microbial additives supplemented to diets of Holstein cows on productive performance and feed efficiency. One-hundred and 17 Holstein cows were enrolled at 61 d (31 to 87 d) postpartum in a randomized complete block design experiment. Cows were blocked by parity group, as nulliparous or multiparous cows and, within parity, by pre-treatment energy-corrected milk yield. Within block, cows were randomly assigned to one of 3 treatments administered as top-dress for 140 d. Treatments consisted of either 100 g of corn meal containing no microbial additive (CON; 15 primiparous and 25 multiparous), 100 g of corn meal containing 5 g of a mixture of Clostridium beijerinckii and Pichia kudriavzevii (G1; 4 × 107 cfu of C. beijerinckii and 1 × 109 cfu of P. kudriavzevii; 14 primiparous and 24 multiparous), or 100 g of corn meal containing 5 g of a mixture of C. beijerinckii, P. kudriavzevii, Butyrivibrio fibrisolvens, and Ruminococcus bovis (G2; 4 × 107 cfu of C. beijerinckii, 1 × 109 cfu of P. kudriavzevii, 1 × 108 cfu of B. fibrisolvens, and 1 × 108 cfu of R. bovis; 15 primiparous and 24 multiparous). Intake of DM, milk yield, and BW were measured daily, whereas milk composition was analyzed at each milking 2 d a week, and body condition was scored twice weekly. Milk samples were collected on d 60 and 62 in the experiment and analyzed for individual fatty acids. The data were analyzed with mixed-effects models with orthogonal contrast to determine the impact of microbial additive (MA; CON vs. 1/2 G1 + 1/2 G2) and type of microbial additive (TMA; G1 vs. G2). Results are described in sequence as CON, G1, and G2. Intake of DM (22.2 vs. 22.4 vs. 22.4 kg/d), BW (685 vs. 685 vs. 685 kg) and the daily BW change (0.40 vs. 0.39 vs. 0.39 kg/d) did not differ among treatments; however, feeding MA tended to increase BCS (3.28 vs. 3.33 vs. 3.36). Supplementing MA increased yields of milk (39.9 vs. 41.3 vs. 41.5 kg/d), ECM (37.9 vs. 39.3 vs. 39.9 kg/d), fat (1.31 vs. 1.37 vs. 1.40 kg/d), total solids (4.59 vs. 4.75 vs. 4.79 kg/d), and ECM per kg of DMI (1.72 vs. 1.76 vs. 1.80 kg/kg). Furthermore, cows fed MA increased yields of pre-formed fatty acids in milk fat (>16C; 435 vs. 463 vs. 488 g/d), particularly unsaturated fatty acids (367 vs. 387 vs. 410 g/d), such as linoleic (C18:2 cis-9, cis-12; 30.9 vs. 33.5 vs. 35.4 g/d) and α-linolenic acids (C18:3 cis-9, cis-12, cis-15; 2.46 vs. 2.68 vs. 2.82 g/d) on d 60 and 62 in the experiment. Collectively, supplementing G1 and G2 improved productive performance of cows with no differences between the 2 MA.

The Effect of a Direct Fed Microbial on Liveweight and Milk Production in Dairy Cattle

This longitudinal study aimed to quantify the effects of dietary supplementation of a direct-fed microbial (DFM) consisting of three lactobacilli isolates on milk yield, milk fat and protein yields, somatic cell count (SCC), and liveweight in a single dairy herd in Australia. A total of 150 dairy cows were randomly selected based on parity and days in milk and divided into two groups: control (n = 75) and DFM treatment (n = 75). Throughout the study, the two groups of cows were housed separately in a dry lot yard, and each group had their own feeding area. For the DFM treatment group, selected cows in mid-lactation were supplemented with 10 mL/cow/day of the DFM via top dressing of the feed for the remainder of the lactation and through the dry period, extending into subsequent lactation. The control group had no supplementation. The milk yield and liveweight were recorded daily. Milk samples were collected every two months for milk component analysis (fat, protein, and somatic cell count [SCC]). The DFM-treated cows gained more liveweight across the study (19.40 kg, 95% CI 0.44 kg; 38.30 kg, p = 0.05) compared to the control cows. In the second production year, the DFM-treated cows mobilized more liveweight (-6.06 kg, 95% CI -10.49 kg; -1.61 kg, p = 0.01) and produced more milk (0.39 L/d 95% CI 0.10; 0.89, p = 0.05). Over a full lactation, DFM cows yielded at least 258 L (95% CI 252 L; 265 L) more milk than controls. No significant differences were found in fat and protein yield or SCC. This study suggests that consistent and ongoing supplementation with a Lacticaseibacillus- and Lentilactobacillus-based DFM could have a positive effect on milk production, but further research is needed to understand the underlying mechanism.

The effect of supplementing native rumen microbes on milk production of dairy cows

We evaluated the effects of 2 direct-fed microbial (DFM) supplements containing 4 native rumen microorganisms on the production of dairy cows. Ninety Holstein cows (43% primiparous) were fed a common diet. Mean days in milk, milk yield, and body weight at the beginning of the study (mean ± standard deviation) were 92 ± 23 d, 45 ± 10 kg/d, and 659 ± 86 kg, respectively. After 14 d, they were blocked by parity, days in milk, and energy-corrected milk (ECM) per unit of metabolic body weight. Within block, cows were randomly assigned to treatments, which were top-dressed daily for the next 112 d. Treatments were 150 g of ground corn mixed with (1) no live DFM (CON), (2) 5 g of a live DFM (Galaxis 2.0; G2), and (3) 5 g of a live DFM (Galaxis 2.0 Plus; G2P). G2 and G2P were products of Native Microbials Inc. (San Diego, CA) and contained the same organisms but in different concentrations. Supplementation with DFM did not alter yield of total milk, protein, or fat, but slightly decreased body weight gain and body condition score gain with no difference between G2 and G2P. The DFM tended to decrease dry matter intake (DMI) and tended to improve ECM/DMI. The DFM did not alter digestibility of fiber, starch, or protein and did not alter concentrations of glucose or nonesterified fatty acids, but tended to decrease concentration of insulin in plasma. Direct-fed microbials decreased somatic cell counts in milk with no difference between G2 and G2P. In conclusion, supplementation with native DFM had little impact on animal production and efficiency.

Feeding native rumen microbial supplements increases energy-corrected milk production and feed efficiency by Holstein cows

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Supplementation with native rumen organisms improves energy-corrected milk production

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The 4-microbe supplement performed better than the 2-microbe supplement

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No negative impact on health or body weight from supplementation

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Production improvements may be influenced by lactation stage

The objective of this study was to investigate the effects of 2 novel native microbial feed supplements (MFS) on milk yield, milk composition, dry matter intake (DMI), body weight (BW), body condition score (BCS), and efficiency. A total of 73 lactating Holstein cows were enrolled over 4 mo. During a 2-wk covariate period, baseline data were collected. Using a randomized complete block design, cows were blocked in groups of 3 by days in milk (DIM), production, and parity. Within blocks cows were randomly assigned to a basal diet with a 150 g/d ground corn topdress and no MFS (control), the basal diet supplemented with a 5 g/d dose of Clostridium beijerinckii ASCUSDY20 and Pichia kudriavzevii ASCUSDY21 in a carrier mixed with a 150 g/d ground corn topdress (MFS1), or the basal diet with a 5 g/d dose of Ruminococcus bovis ASCUSDY10, Butyrivibrio fibrisolvens ASCUSDY19, Clostridium beijerinckii ASCUSDY20, and Pichia kudriavzevii ASCUSDY21 in a carrier mixed in a 150 g/d ground corn topdress (MFS2) for 140 d. Cows were fed the diets as a total mixed ration (TMR) for ad libitum DMI once daily. Analysis showed numerical increases in performance variables such as milk yield and fat and protein contents in both MFS1 and MFS2, although the differences were not significant over time. For energy-corrected milk (ECM), other solids percentage, and BW there were significant treatment by time interactions. Cows fed MFS1 and MFS2 produced 1.4 kg/d and 1.6 kg/d more ECM than control cows, respectively (time-dependent treatment significance). Up to wk 13 of treatment, both MFS groups had higher ECM production than the control group but after this point MFS1 rapidly decreased to the same level as control. All cows displayed a gradual decrease in ECM after wk 13 but the MFS2 group remained greater than both control and MFS1. A similar trend in the content of other milk solids was observed. Cow BW was affected over time; both control and MFS2 cows gained weight at a similar rate throughout the study, whereas the weight gain of MFS1 cows decreased briefly from wk 13 to 17 before increasing again. Feed efficiency tended to be improved by MFS, with greater improvement by MFS2 than by MFS1. The DIM when the supplementation began had a significant impact on MFS2 efficacy, where the supplementation of native rumen microbes at an earlier DIM resulted in a greater gain in ECM over the 140-d trial. A similar trend was observed for MFS1, although the effect was not significant. Our results suggest that dairy cow lactation stage and energy requirements also play an important role in product efficacy.

The Transition Period Updated: A Review of the New Insights into the Adaptation of Dairy Cows to the New Lactation

Recent research on the transition period (TP) of dairy cows has highlighted the pivotal role of immune function in affecting the severity of metabolic challenges the animals face when approaching calving. This suggests that the immune system may play a role in the etiology of metabolic diseases occurring in early lactation. Several studies have indicated that the roots of immune dysfunctions could sink way before the “classical” TP (e.g., 3 weeks before and 3 weeks after calving), extending the time frame deemed as “risky” for the development of early lactation disorders at the period around the dry-off. Several distressing events occurring during the TP (i.e., dietary changes, heat stress) can boost the severity of pre-existing immune dysfunctions and metabolic changes that physiologically affect this phase of the lactation cycle, further increasing the likelihood of developing diseases. Based on this background, several operational and nutritional strategies could be adopted to minimize the detrimental effects of immune dysfunctions on the adaptation of dairy cows to the new lactation. A suitable environment (i.e., optimal welfare) and a balanced diet (which guarantees optimal nutrient partitioning to improve immune functions in cow and calf) are key aspects to consider when aiming to minimize TP challenges at the herd level. Furthermore, several prognostic behavioral and physiological indicators could help in identifying subjects that are more likely to undergo a “bad transition”, allowing prompt intervention through specific modulatory treatments. Recent genomic advances in understanding the linkage between metabolic disorders and the genotype of dairy cows suggest that genetic breeding programs aimed at improving dairy cows’ adaptation to the new lactation challenges (i.e., through increasing immune system efficiency or resilience against metabolic disorders) could be expected in the future. Despite these encouraging steps forward in understanding the physiological mechanisms driving metabolic responses of dairy cows during their transition to calving, it is evident that these processes still require further investigation, and that the TP—likely extended from dry-off—continues to be “the final frontier” for research in dairy sciences.