This study was designed to investigate the carryover effects of high-forage to concentrate (F: C) diet in bred heifers on feed intake, feed efficiency (FE) and milk production of primiparous lactating Holstein cows. The experiment was conducted for 589 days (d) from onset of pregnancy through to the end of first lactation. Twenty-four bred heifers (Body weight: BW= 345.8 ± 45.4 kg and 15 ± 1.2 mon of age) randomly assigned to two groups of 3 pens containing 4 heifers each and fed high forage (HF) diet with F: C ratio of 91.7: 8.3% and low forage (LF) diet with F: C ratio of 77.8: 22.2% throughout the pregnancy period. After calving, lactating cows were fed total mixed ration (TMR) based diet. No differences (p > 0.05) were observed in dry matter intake (DMI) of bred heifers and primiparous lactating cows in both HF and LF groups. The FE of mid-to-late lactation period was higher (p< 0.05) in HF than LF group. However, the HF group showed higher (p < 0.05) milk yield, 4 % fat corrected milk (FCM) and energy corrected milk (ECM) than LF group during the 305 d lactation. The LF group showed higher (p < 0.05) milk fat, crude protein (CP), milk urea nitrogen (MUN), solid not fat (SNF) and somatic cell count (SCC) than HF group. It is concluded that restriction of F: C ratio to 91.7: 8.3% to bred heifers has the potential carryover effects to maintain higher milk yield and FE with no adverse effect on feed intake and milk composition of primiparous lactating Holstein cows.

The purpose of this study was to investigate the effect of calcium (Ca) and vitamin D (vit. D) levels on metabolism of various minerals such as Ca, P, Mg, Fe, Zn, Cu, and Cr. The comparison was made on the rats that were placed on diet containing powdered skim milk with different Ca and vit. D levels for 5 weeks. A total of 42 5-week-old Sprague- Dawley rats were divided into 7 groups as follows: Control group consisted of normal Ca and normal vit. D (0.5% Ca, 1,000 IU vit. D); Experimental groups were divided into low (0.25%) and high (1.0%) calcium levels; and vit. D group was divided into low (10 IU), normal (1,000 IU), and high (5,000 IU) subgroups. The weight gain and food efficiency ratios of the rats were not significantly different with increasing dietary Ca levels. The absorption rates of 7 minerals (Ca, P, Mg, Fe, Zn, Cu, and Cr) were significantly decreased with increasing dietary Ca levels. Also, fecal excretion of P significantly increased with increasing dietary vit. D levels (p<0.05), and urine excretion of Fe was significantly increased with increasing dietary vit. D levels (p<0.001). The result indicated that higher Ca intake affected on bioavailability of other minerals, due to interactions among minerals in the process of intestinal absorption. However, vitamin D intake had no effect on bioavailability of several minerals. Therefore, it could be suggested that adequate Ca intake is important for balance of the minerals.

The aim of the present study was to determine the effect of dietary cultured wild ginseng root (CWGR) supplementation on goat milk composition and ginsenoside profiles. Sixteen Saanen dairy goats were allocated to two balanced groups based on lactation period, body weight (38.6 ± 3.2 kg), and dairy milk yield (2.85 ± 1.2 kg), and were kept in separate pens. Goats were fed a total mixed ration (TMR) feed (2.3 kg/d, dry matter basis) and 1.5 g of CWGR powder was supplemented in the experimental diet. The total feeding period was 3 weeks, and milk and blood samples were collected on the last three days of the experimental period. There was no effect of CWGR on daily milk yield and milk composition (fat, protein, lactose, and solid-not-fat). However, the CWGR-treatment group had significantly higher plasma IgG and protein contents than the control group (P < 0.05). Significant amounts of ginsenosides were observed in the milk of the CWGR-treatment group, whereas ginsenosides were not detected in the milk of the control group. In conclusion, dietary CWGR was a useful regimen to produce functional goat milk enriched in ginsenosides.