Encapsulation of soybean meal with fats enriched in palmitic and stearic acids: effects on rumen-undegraded protein and in vitro intestinal digestibility.

Fat coating of soybean meal (SBM) can reduce its protein degradability in the rumen, but the encapsulation of SBM with palmitic (PA) and stearic acids (SA) has not yet been investigated, despite both fatty acids are common energy sources in dairy cow diets. This study aimed to evaluate the effects of applying a novel method, using either 400 or 500 g fat/kg (treatments FL40 and FL50, respectively), which was enriched in PA and SA at different ratios (100:0, 75:25, 50:50, 25:75 and 0:100), on physical and chemical characteristics, ruminal degradability, solubility and in vitro intestinal protein digestibility (IVIPD) of the obtained products. Encapsulation of SBM in fat resulted in greater mean particle size and lower bulk density and protein solubility than unprotected SBM (USBM). Treatment FL50 resulted in increased (p < 0.01) rumen-undegraded protein (RUP) compared to USBM. There were no differences in RUP of SBM when different PA: SA ratios were used. The mean RUP content of treatments FL40 and FL50 (306 and 349 g/kg, respectively) was greater compared to USBM (262 g/kg, p < 0.05), but lower than that for a standard heat-treated SBM (431 g/kg). Values of IVIPD did not differ among SBM, heat-treated SBM and FL40 and FL50 samples, all being greater than 97.8%. In conclusion, encapsulation of SBM with fats enriched in PA and SA proved to be effective in reducing protein solubility and increasing RUP without depressing protein digestibility in the intestine. For validation of the method, in vivo research to investigate the effects of these products on the production of dairy cows is warranted.

Assessing the protective effect of bentonite against lead toxicity in growing lambs.

The objective of the present experiment was to investigate the effect of bentonite supplementation in lead (Pb)-exposed lambs on serum Pb, Ca, P, Cu, Zn, and Fe concentrations, blood hematological parameters, and hepatic enzymes. Twenty Zandi male lambs (initial BW, 17.5 ± 1.6 kg) were randomly assigned to one of the four treatments: (1) control (no Pb or bentonite), (2) 15 mg/kg DM Pb as Pb acetate with no bentonite, (3) 15 mg/kg DM Pb as Pb acetate with 1.5% bentonite, and (4) 15 mg/kg DM Pb as Pb acetate with 3% bentonite. The experiment lasted after 90 days. Lead intake resulted in a decrease (P < 0.05) in serum Fe and an increase in serum Pb, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) activities (P < 0.05). Bentonite supplementation at 1.5 or 3% of DM decreased blood Pb concentration (P < 0.01) in lambs fed diets containing Pb and reduced (P < 0.05) blood concentration of Cu and Zn compared to control group (P < 0.01). However, the hematological parameters were not affected by any of the treatments. Our results showed that the dietary supplementation of bentonite could protect lambs against lead toxicity.

Linolenic acid improves oocyte developmental competence and decreases apoptosis of in vitro-produced blastocysts in goat.

The effects of α-linolenic acid (ALA) on developmental competence of oocytes in goats were evaluated in this study. Initially, the level of ALA in small and large antral follicles was determined to be in a range of 0.018-0.028 mg/ml (64.6-100.6 µM, respectively). In vitro maturation was performed in the presence of various concentrations (10, 50, 100, or 200 µM) of ALA. Cumulus expansion, meiotic maturation, levels of intracellular glutathione (GSH), embryonic cleavage, blastocyst formation following parthenogenetic activation (PA) and in vitro fertilization (IVF), number of total and apoptotic cells in blastocyst, and expression of Bax, Bcl-2, and p53 genes in blastocyst cells were determined. Compared with the control, no improvement was observed in cumulus expansion in ALA-treated groups. At 50 µM concentration, ALA increased meiotic maturation rate but had no effect on GSH level. When oocytes treated with 50 µM ALA were subsequently used for PA or IVF, a higher rate of blastocyst formation was observed, and these embryos had a higher total cell number and a lower apoptotic cell number. Expression analyses of genes in blastocysts revealed lesser transcript abundances for Bax gene, and higher transcript abundances for Bcl-2 gene in 50 µM ALA group. Expression of p53 gene was also less observed in ALA-treated blastocysts. Our results show that ALA treatment at 50 µM during in vitro maturation (IVM) had a beneficial effect on maturation of goat oocytes and this, in turn, stimulated embryonic development and regulated apoptotic gene expression.

Effect of Linolenic acid during in vitro maturation of ovine oocytes: embryonic developmental potential and mRNA abundances of genes involved in apoptosis.

PURPOSE: To study the effect of α-linolenic acid (ALA) on meiotic maturation, mRNA abundance of apoptosis-related (Bax and Bcl-2) molecules, and blastocyst formation in ovine oocytes. METHODS: A preliminary experiment was conducted to analyze the concentration of ALA in "small" (≤2 mm) and "large" (≥6 mm) follicles using gas chromatography/mass spectrometry analysis. The concentration of ALA in small and large follicles was determined to be in a range of 75.4 to 125.7 µM, respectively. In vitro maturation (IVM) of oocyte was then performed in presence of 0 (control), 10 (ALA-10), 50 (ALA-50), 100 (ALA-100), and 200 (ALA-200) µM of ALA. Meiotic maturation and mRNA abundance of Bax, and Bcl-2 genes was evaluated after 24 h of IVM. The embryonic cleavage and blastocyst formation following parthenogenetic activation were also determined for each group. RESULTS: The highest concentration of ALA (ALA-200) decreased the oocyte maturation rate compared with the control group. Analysis of apoptosis-related genes in oocytes after IVM revealed lesser transcript abundances for Bax gene, and higher transcript abundances for Bcl-2 gene in ALA-treated oocytes as compared with the control oocytes. In term of cleavage rate (considered as 2-cell progression), we did not observe any differences among the groups. However, ALA-100 group promoted more blastocyst formation as compared with the control group. CONCLUSION: Our results suggested that ALA treatment during IVM had a beneficial effect on developmental competence of ovine oocytes by increasing the blastocyst formation and this might be due to the altered abundance of apoptosis-regulatory genes.

Effects of diets containing alfalfa hay or barley flour mixed alfalfa silage on feeding behavior, productivity, rumen fermentation and blood metabolites in lactating cows.

The effects of barley flour on the fermentation parameters of alfalfa silage and on the productivity of dairy cows were investigated. Alfalfa forage was ensiled either with or without barley flour. Barley flour was soaked in water for 24 h before being mixed with alfalfa (12 kg: 100 kg dry matter bases) at ensiling. Eighteen multi-parous cows were assigned to three equal treatment groups using a completely randomized design. Three isocaloric and isonitrogenous total mixed rations containing alfalfa hay, ordinary alfalfa silage or barley flour mixed alfalfa silage were then prepared. The concentrations of ammonia nitrogen, acetic acid and butyric acid were lower in barley flour mixed alfalfa silage compared to that in ordinary alfalfa silage but the concentration of lactic acid was lower in the ordinary alfalfa silage. Feeding behavior, milk yield and composition, ruminal fermentation and blood metabolites were measured. Although dry matter intake and milk production were not affected, the effect of preparation of alfalfa influenced feeding behavior and rumen fermentation parameters. Cows on alfalfa silage diets spent longer ruminating compared to those fed alfalfa hay. The ruminal ammonia nitrogen and blood urea were affected by ensiling (alfalfa hay versus alfalfa silages) while both parameters were lower in cows fed on barley flour mixed alfalfa silage than those fed on ordinary silage. Although similar blood glucose was recorded for cows fed on alfalfa silages, it was higher in cows fed on alfalfa hay. It is concluded that the addition of barely flour when making alfalfa silage may improve both the fermentation process during ensilage and the ruminal ammonia nitrogen utilization with no significant effects on productivity.