Short communication: Effect of purple corn pigment on change of anthocyanin composition and unsaturated fatty acids during milk storage.

Unsaturated fatty acids (UFA) in milk give rise to radicals and lead to lipid oxidation during storage, reducing the commercial value of milk. The objective of this study was to observe the effect of anthocyanins from purple corn pigment on the oxidation of UFA in milk. Milk samples were randomly divided into 2 groups: (1) the control (without purple corn pigment) and (2) treatment (0.3% purple corn pigment), using a completely randomized design. The milk samples were placed into plastic tubes and stored at 4°C for a period of 0, 1, 3, and 7 d. Individual anthocyanin composition and UFA were detected by HPLC-mass spectrometry and gas chromatography-mass spectrometry, respectively. The results indicated that pelargonidin (0.258 vs. 0.054 µg/mL), cyanidin (5.550 vs. 1.808 µg/mL), petunidin (0.464 vs. 0.107 µg/mL), delphinidin (2.061 vs. 0.123 µg/mL), and total anthocyanin (8.332 vs. 2.091 µg/mL) significantly decreased in response to increasing storage day. Of interest, purple corn pigment had a significant effect on most of the UFA (C14:1n-5, C16:1n-7, C18:1n-9, C18:2n-6, C18:3n-3, C18:3n-6, C20:2n-6, C20:3n-3, and C20:4n-6), except for C17:1n-7 and C20:3n-6. Specifically, various stronger positive correlations were noted for anthocyanin composition and UFA (pelargonidin and petunidin with C14:1n-5, C17:1n-7, C18:2n-6, C20:2n-6, C20:3n-3, and C20:4n-6; and cyanidin and total anthocyanins with C14:1n-5, C16:1n-7, C17:1n-7). Collectively, the current study suggested that the addition of anthocyanins from purple corn pigment had the potential to maintain UFA concentrations in milk during the storage period.

Effects of crude protein and undegradable intake protein on growth performance, nutrient utilization, and rumen fermentation in growing Thai-indigenous beef cattle.

The objective of this study was to investigate growth performance, nutrients apparent digestibility, nitrogen utilization, rumen fermentation, and rumen microorganism of growing Thai-indigenous beef cattle receiving different levels of crude protein (CP) and undegradable intake protein (UIP) diets. Eighteen healthy growing Thai-indigenous beef cattle were used in a 2 × 3 factorial randomized complete block design (RCBD). There were six treatments: two levels of CP (10% and 12% of dry matter (DM)) and three levels of UIP (15%, 25%, and 35% of CP). The results indicated that dry matter intake (DMI) and average daily gain (ADG) increased linearly (P < 0.01) with increasing UIP level. The apparent digestibility of DM, organic matter (OM), acid detergent fiber (ADF), and neutral detergent fiber (NDF); rumen fermentation parameters; microbes counts; and microbial nitrogen synthesis (MNS) were unaffected (P > 0.05) by CP and UIP levels. The nitrogen (N) intake and N retained increased linearly (P < 0.01) with increasing UIP level. Specifically, the metabolizable protein (MP) requirement of 1 g/kg BW0.75 gain was 0.34 g MP/kg BW0.75; the 10% dietary CP of DM was able to meet animals' normal nutrition requirements and 6.5% DIP of DM can provide adequate N source for the requirement of rumen microbe growth in. Collectively, it was indicated that the supplemental level of 10% CP and the ratio of UIP to DIP was 35:65 in diets shown the best growth performance for growing Thai-indigenous beef cattle under the conditions in the current study.

Short communication: Purple corn (Zea mays L.) stover silage with abundant anthocyanins transferring anthocyanin composition to the milk and increasing antioxidant status of lactating dairy goats.

The present study used 16 multiparous lactating Saanen dairy goats (body weight, 41.80 ± 2.92 kg; mean ± standard deviation) with healthy and symmetrical udders. Goats were divided into 2 blocks of 8 goats based on milk yield averaged from 75 d in milk in a randomized completed block design. The 2 study groups were the control (CSSS), in which goats were fed sticky corn stover silage, and the treatment (TPSS), in which goats were fed anthocyanin-rich purple corn (Zea mays L.) stover silage (PSS). The results indicated that the TPSS group led to an elevation in the content of milk lactose relative to the CSSS. The inclusion of anthocyanin-rich PSS had no effect on the level of 5 particular anthocyanins [i.e., cyanidin-3-glucoside, delphinidin, cyanidin, pelargonidin (Pel), as well as total anthocyanins in milk]. The pelargonidin-3-glucoside and malvidin were unable to be detected in both groups. However, the TPSS resulted in higher levels of peonidin (Peo) and malvidin-3-O-glucoside (M3G) compared with the control. Moreover, goats receiving TPSS exhibited a higher level of superoxide dismutase (SOD) in plasma and milk relative to the CSSS. Interestingly, some positive correlations were detected between the certain milk components [i.e., fat and total solids as well as fat and solids-not-fat (SNF); protein and SNF; and total solids and SNF]. In addition, the positive correlations were observed between individual anthocyanins (cyanidin-3-glucoside, delphinidin, Peo, M3G, cyanidin, and Pel) and total anthocyanins. Specifically, stronger positive correlations were noted between several antioxidant enzymes and anthocyanin composition in milk (total antioxidant capacity and Pel; SOD and Peo as well as SOD and M3G). Taken together, PSS with abundant anthocyanins can transfer anthocyanins to the milk and enhance the amount of antioxidants in lactating dairy goats.

Effects of supplementing rice straw with Leucaena (Leucaena leucocephala) and Madras thorn (Pithecellobium dulce) foliages on digestibility, microbial N supply and nitrogen balance of growing goats.

A total of 12 crossbred (Boer × Anglo-Nubian) goats were chosen from a commercial farm on the basis of similar body weight (25.0 ± 3.1 kg). The goats were housed in individual pens and allowed 3 weeks to adapt to experimental conditions. The goats were randomly allocated to three treatments in a 3 × 3 Latin square experiment (replicated four times). Within each period, each goat was given rice straw as roughage plus the respective treatment diet. The diets were iso-nitrogenous and iso-energetic containing cassava pulp, molasses, urea and commercial mineral and vitamin mix. The experimental treatments were (i) soybean meal (SBM), (ii) partial substitution of SBM with Leucaena (Leucaena leucocephala) foliage and (iii) partial substitution of SBM with Madras thorn (Pithecellobium dulce) foliage. Nutrient intakes, ruminal characteristics (pH, ammonia nitrogen and volatile fatty acids), nitrogen balances, plasma urea nitrogen and microbial N supply were not significantly different among treatments. The results of this study indicate that protein foliages from locally grown shrubs and trees can substitute imported feedstuff concentrates (e.g. SBM) as protein supplement for goat production.