RESUMO
The aim of the present study was to compare the effect of feeding a newly produced bacteriocin-like substance from Lactococcus lactis ssp. lactis (PNP) with a commercial bacteriocin (NISEEN-S; CNP) in lactating Rahmani ewe diets. In experiment 1, the effects of four levels (500, 1,000, 1,500, and 2,000 unit/kg substrate, dry matter (DM) basis) of both bacteriocins on in vitro ruminal fermentation kinetics, total gas production (TGP), methane production (CH4), and nutrient degradability were determined. In experiment 2, 2 wk before the expected parturition, 30 multiparous lactating Rahmani ewes (mean ± SD: 2 ± 0.3 parity, 46.8 ± 2.5 kg body weight, 23 ± 2.7 mo of age, and 370 ± 13 g/d of previous milk production) were equally divided into three treatments in a complete randomized design for 90 d. The ewes in the control treatment were offered a diet composed of 600 g of concentrate feed mixture, 300 g berseem hay, and 100 g of faba bean straw (Control), or supplemented with produced bacteriocin like substance (PNP) or commercial (CNP) bacteriocin at 500 unit/kg feed (DM basis). In experiment 1, both PNP and CNP linearly and quadratically decreased (P < 0.001) CH4 production; however, PNP and CNP at 500 unit/kg feed quadratically increased fiber degradability (P < 0.01). In experiment 2, both PNP and CNP increased (P < 0.05) nutrient digestibility, and ruminal total volatile fatty acids, acetate, and propionate, while decreasing ruminal ammonia-N. The PNP treatment increased (P < 0.05) blood total proteins and albumin, while PNP and CNP treatments increase serum glucose. Both PNP and CNP treatments increased (P < 0.05) daily milk production and milk efficiency, without affecting the concentration of milk components. Both PNP and CNP are recommended to improve feed utilization and milk production, with superior results detected for PNP at 500 unit/kg feed daily.
RESUMO
The objective of this study was to determine the ability of an isolated strain (EGY_NRC1) or commercial (NCIMB 11181) Enterococcus faecium as a probiotic for lactating cows. Two experiments were conducted: In Experiment 1, the effects of three levels (1, 2, and 3 g/kg diet, DM basis) of isolated and commercial E. faecium on in vitro ruminal fermentation kinetics, gas, methane (CH4) and nutrient degradability were determined. In Experiment 2, thirty multiparous Holstein cows (633 ± 25.4 kg body weight) with 7 days in milk, were randomly assigned to 3 treatments in a completely randomized design in a 60-day experiment. Cows were fed without any additives (control treatment) or supplemented with 2 g/kg feed daily of E. faecium EGY_NRC1 (contain 1.1 × 109 CFU/g) or commercial E. faecium NCIMB 11181 (contain 2 × 1012 CFU/g). Diets were prepared to meet cow's nutrient requirements according to NRC recommendations. Probiotic doses were based on the in vitro Experiment 1. Feed intake, digestibility, blood parameters and lactation performance were evaluated. In Experiment 1, the isolated E. faecium linearly and quadratically increased (P < 0.001) in vitro total gas production (TGP), the degradability of dry matter (dDM) and organic matter (dOM) while decreased (P < 0.05) methane (CH4) percent of TGP, NH3CH4 production, and pH. The commercial E. faecium increased TGP and decreased (P < 0.01) CH4 production, pH and increased the dDM and dOM, short chain fatty acids and ruminal NH3-N concentration. In Experiment 2, the isolated E. faecium increased (P < 0.01) total tract digestibility of DM, neutral and acid detergent fiber, daily milk production and feed efficiency compared to the control treatment without affecting feed intake and milk composition. Moreover, the isolated E. faecium increased (P < 0.05) the proportion of C18:1 trans-9, C18:2 cis-9-12 and C18:2 trans-10 cis-12. Both isolated and commercial E. faecium improved (P < 0.01) organic matter, crude protein and nonstructural carbohydrates digestibility, increased serum glucose (P = 0.002) and decreased serum cholesterol (P = 0.002). Additionally, both E. faecium strains decreased C23:0 (P = 0.005) in milk. In conclusion, the use of E. faecium (isolated and commercial) at 2 g/kg DM of feed improved feed efficiency and production performance, with superior effects on animal performance from isolated E. faecium compared to the commercial one.
RESUMO
The experiment was conducted to study the effects of supplementing a cellulase enzymes cocktail to lactating buffaloes' diet, on the nutrient intake, nutrient digestibility, and milk production performance and composition. Twenty-four lactating Egyptian buffaloes were assigned into one of the following treatments: CON-control consisted of a total mixed ration, CENZ-the total mixed ration supplemented by a commercial source of cellulase enzyme, FENZ-the total mixed ration supplemented with cellulase enzyme cocktail produced in-farm. Supplementing the diet with the in-farm source of cellulase (FENZ) had a significantly higher impact on crude protein, neutral detergent fiber, and acid detergent fiber digestibility. However, FENZ tended to increase the EE digestibility compared to CENZ. FENZ showed significantly higher nutrient digestibility percentages compared to other groups. Supplementing the diet with cellulase enzymes (CON vs. ENZ) significantly increased the daily milk yield and the fat correct milk yield; both yields were significantly higher with FENZ than all groups. Oleic, linoleic, and linolenic acid concentration were significantly higher with cellulase enzymes supplementation (CON vs. ENZ) and the conjugated linoleic acid concentration. Supplementing fungal cellulase enzyme produced on a farm-scale has improved milk productivity, fat yield, and milk fat unsaturated fatty acids profile in lactating buffaloes.
