OreganoExtract Added into the Diet of Dairy Heifers Changes Feeding Behavior and Concentrate Intake

Abstract

This experiment aimed to describe the effects of Oregano extract (OE) inclusion into the concentrate fed to dairy heifers on physiological parameters, feeding behavior, intake, and performance. Thirty-two Holstein heifers were randomly distributed into four treatments: C = control, without addition of OE; OE2.5 = 2.5 g; OE5.0 = 5.0 g and OE7.5 = 7.5 g of Oregano extract per heifer/day. Feeding behavior and concentrate intake were assessed individually every day and total dry matter intake (DMI) was determined on the last week of the trial. Compared to control group, OE7.5 reduced by 32% the latency time to approach the feed bunk but increased by 6% the time spent eating the concentrate. Each inclusion of 2.5 grams of OE into the concentrate increased the occurrence of postingestive licking the feed bunk with abundant saliva production 1.2 times (P < 0.01) and tended to increase the occurrence of sneeze events 1.2 times (P < 0.10). No statistical difference was detected between treatments for total DMI, but concentrate DMI was 9% lower for OE7.5 when compared to control and OE2.5. The inclusion of 7.5 grams/day of OE causes small but negative effects in feeding behavior and concentrate intake, without change on total dry matter intake.

Calves fed with milk from cows receiving plant extracts improved redox status

“…Essential oils in oregano and polyphenols in green tea may alter smell and taste in feeds (Oh et al, 2017) but apparently it was not enough to change calves' intake. These results are in agreement to results of previous studies when oregano and green tea extracts were fed directly to heifers and dairy cows and did not significantly affect productive variables such body weight gain and diet intake (Aemiro et al, 2016;Kolling et al, 2016;2018;Stivanin et al, 2019).…”

Potential benefits of early-life supplementation of liquid feed with fennel (Foeniculum vulgare) seeds or oregano (Origanum vulgare) leaves on growth, health, and blood metabolites in Holstein dairy calves

“…Consistent with the results of the present study, supplementing the diet with OLP or oregano essential oil/extract increased the feed intake in milk-fed calves (Tapki et al, 2020), broiler chickens (Ri et al, 2017), goats (Lei et al, 2018), and dairy cows (Bosco Stivanin et al, 2019). However, decreased feed intake or nonsignificant effects on intake were also reported (Bampidis et al, 2005;Chaves et al, 2008;Hristov et al, 2013;Kolling et al, 2016Kolling et al, , 2018Wu et al, 2021), indicating the need for further clarification of the conditions for the use of FSP or OLP in various animal species. Overall, the observed intake of starter feed was substantially lower than when liquid feed intake is restricted, and current values are well in line with other studies (e.g., Berends et al, 2020).…”

“…Rectal temperature was in the physiological range (38.1-39.2°C; Kargar et al, 2018a,b;Heisler et al, 2020), indicating a reasonable calf ability to cope with the potential thermal stress in the present study, especially in FSP-supplemented calves that recorded lower rectal temperature. It has been shown that feeding oregano extract to Holstein heifers (at 2.5, 5.0, and 7.5 g/d; Kolling et al, 2016) or preweaning Jersey calves (at 60 mg/kg of BW per day; Heisler et al, 2020) did not affect rectal temperature under thermoneutral conditions; however, to the best of our knowledge, similar data are not available for comparison with our findings. Nowroozinia et al (2022) reported lower susceptibility to having elevated rectal temperature and fewer days with elevated rectal temperature when milk-fed calves received FSP at 1.5 or 3 g/d.…”

A Review on Phytochemicals (Including Essential Oils and Extracts) Inclusion in Feed and Their Effects on Food Producing Animals

“…Gunal and coworker's used anise, cedar wood, cinnamon, eucalyptus, and tea tree oils and incubated them with ruminal fluid. Except for the case of the cinammon oil treatment, the proportions of acetate, propionate, and acetate to propionate ratios were not affected by the addition of the essential oil [78]. Addition of cedar wood, cinnamon and tea tree oils, reduced total volatile fatty acids concentrations regardless of dose level and all oils reduced C 18:0 and trans C 18:1 (both products of bio hydrogenation).…”