Effects of yucca extract and organic chromium on growth performance and health of lactating lambs

Abstract

Abstract Organic chromium and yucca extract (main components saponins) have functional properties that can stimulate desirable antioxidant and anti-inflammatory responses and consequently enhance the weight gain. Thus, the effects of supplementation with organic chromium and yucca extract (alone or in combination) on growth and health in lactating lambs were measured. Sixty-four Lacaune lambs aged 18 ± 2.5 days, were divided into 16 pens (four pen/treatment; four lambs/pen). All lambs received the same basal diet, consisting of corn silage, concentrate and a mixture of sheep's milk and milk replacer (50/50 v/v). The experiment lasted 40 days, i.e., starting with 18-day-old animals. All animals received the same feeding and management, differing only in terms of supplementation: control treatment (no supplementation); yucca treatment (YE) with 250 mg yucca extract per kg concentrate; chromium treatment (OC) with 2 mg organic chromium per kg concentrate; combined treatment (YE + OC) lambs received supplementation of yucca extract (250 mg/kg) and organic chromium (2 mg/kg). At days 0, 15, 30 and 40 of the experiment, the animals were weighed and blood samples were collected for analysis of hemogram, serum biochemistry and antioxidant status. All data were analyzed using MIXED procedure of SAS. Lambs of YE + OC treatment had significantly greater weight gain, compared to others groups. Supplementation influenced the white blood cell count, manifesting as lower numbers of total leukocytes in the YE + OC treatment than in the controls (days 15, 30 and 40), attributable to reductions in neutrophil and lymphocyte counts. Lambs from OC treatment also had fewer leukocytes, neutrophils, and lymphocytes on days 30 and 40. Significantly greater levels of total proteins and globulins (YE, OC, and YE + OC) were observed on day 40 than in controls. Lipid metabolism was altered by treatments, in particular manifesting as increased cholesterol in the YE + OC combination group. There were lower reactive oxygen species in groups YE and YE + OC than in controls during the experimental period, as well as in group OC on days 30 and 40. These data suggest that chromium supplementation and yucca extract, alone or in combination, increased serum activity of antioxidant enzymes (catalase and superoxide dismutase). Thus, organic chromium and yucca extract when used alone alter response parameters; however, the combination of the two improves animal health response parameters, as well as growth performance.