Meadow Feeds

South Africa

Meadow Feeds

South Africa
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Robinson P.H.,University of California at Davis | Swanepoel N.,Meadow Feeds | Evans E.,Essi Evans Technical Advisory Services
Animal Feed Science and Technology | Year: 2010

The literature on post-ruminal lysine supplementation to diets of lactating dairy cows shows generally small negative responses to supplemental intestinally absorbable lysine, and our recent metabolic modeling of California dairy rations predicted other amino acid (AA) that could become co-limiting if supplies of intestinally absorbable lysine were met. The objectives of this study were to estimate the rumen escape potential of a ruminally protected (RP) lysine (RPL) product, and an RPL product also containing isoleucine, valine and histidine (RPAA), to determine effects of feeding these products on performance and plasma AA profiles of high producing dairy cows. Three pens of about 310 multiparous early lactation cows were used in a 3 × 3 Latin square design with 28 day experimental periods in which the basal total mixed ration (TMR) was the same for all groups except for the RP products which were added to the treatment pens at a level designed to deliver an equal amount of intestinally absorbable l-lysine to both RP groups. However rumen stability was slightly higher for the RPL versus the RPAA, and the RPL was calculated to deliver ∼13.2 g/d of intestinally absorbable lysine and the RPAA calculated to deliver ∼10.6, 5.4, 2.2 and 1.6 g/d of intestinally absorbable lysine, isoleucine, histidine and valine respectively. Only milk protein proportion was increased when RPL was fed. However, replacement of the RPL with the RPAA increased milk and milk lactose yields, while milk protein and energy outputs tended to increase. Plasma levels of both non-essential and essential AA, including lysine, were not impacted by feeding the RPL or RPAA. Overall, feeding the RPL alone was judged to cause a generally reduced productive performance, which could be interpreted to suggest that lysine was not supplied in sufficient quantity or that it was not required. Feeding the RPAA versus the RPL increased productive performance of the cows overall, which could support an overall hypothesis that lysine alone resulted in an imbalance and/or deficiency of isoleucine, histidine and/or valine which was alleviated by their supplementation. Overall treatment differences, regardless of their statistical significance, were small and of very limited practical application. Nevertheless, feeding a complex of RPAA was beneficial beyond supplementation of RP lysine alone, but more research on AA imbalances will be required in order to determine effects of supplementation of RP amino acids. © 2010 Elsevier B.V.


Robinson P.H.,University of California at Davis | Swanepoel N.,Meadow Feeds | Shinzato I.,Ajinomoto Co. | Juchem S.O.,University of California at Davis
Animal Feed Science and Technology | Year: 2011

Increased milk production requires high intakes of crude protein in the diet, and/or improved supply and profiles of amino acids (AA) delivered to the duodenum, in order to meet animal needs for milk and milk component synthesis. Our objective was to estimate the rumen escape of a ruminally protected lysine (RPL) product and determine effects of feeding it on dry matter (DM) intake, milk production and plasma AA profiles of high producing dairy cows. The study was two 2 × 2 crossovers (i.e., early and mid-lactation dairy cows) with 28-d experimental periods. All cows were fed the same total mixed ration (TMR), calculated to be first limiting in lysine, with treatment pens receiving 17. kg/pen/d of the RPL supplement (to deliver 41. g of lysine/cow/d) mixed into the TMR. Extensive evaluation of the RPL suggested that this feeding level delivered 15-21. g/d of intestinally absorbable lysine. Control cows were fed the RPL without lysine (i.e., the fat matrix) at the same level as the fat matrix which was fed to the RPL cows. Feeding the RPL did not influence DM intake in early lactation cows (26.8. kg/d), but production of milk (48.0 versus 50.0. kg/d), as well as milk fat, true protein and lactose, and energy, were higher (P<0.01) in RPL supplemented cows. In addition, cows supplemented with RPL gained body condition score (BCS) whereas control cows lost BCS during the 28-d period (i.e., 0.020 versus -0.069. units/28. d; P=0.056). In mid-lactation cows, DM intake was not influenced, and only milk fat and energy outputs increased (P<0.05) with RPL feeding. BCS change was not influenced. Plasma lysine levels in mid-lactation cows were much higher (P=0.01) with RPL feeding, suggesting that the feeding level of RPL exceeded their lysine needs. However a lack of impact of RPL feeding on plasma lysine levels in early lactation cows suggests that lysine needs may not have been met with RPL feeding. In contrast to an earlier study by our group, with early lactation cows fed a similar diet where milk yield was not impacted by 7-10. g/d of lysine delivered to the intestinal absorptive sites, may support the unconventional hypothesis advanced in that study that body protein turnover is the first limiting AA priority in early lactation cows followed by milk component synthesis. © 2011 Elsevier B.V.


van der Walt K.E.,Meadow Feeds | Einkamerer O.B.,University of the Free State | van Der Merwe H.J.,University of the Free State | Hugo A.,University of the Free State | And 2 more authors.
South African Journal of Animal Sciences | Year: 2014

The effect on production performance of a synthetic or natural antioxidant and lipid saturation in the finishing diets of lambs was investigated. The four dietary treatments consisted of the same basal diet (187 g CP, 355 g NDF, and 71 g EE per kg DM), differing only in regard to the supplemental lipid source (30 g/kg of either saturated beef tallow or unsaturated soybean oil) and type of antioxidant (125 g/ton of either a synthetic or natural antioxidant) included, in a 2 × 2 factorial design experiment. Eighty-four S.A. Mutton Merino lambs (27.64 ± 1.72 kg) were randomly allocated to the four dietary treatments (n = 21 lambs per treatment) and subdivided into 7 replicates per treatment (n = 3 lambs per replicate). After a dietary adaptation period of 8 days, all lambs received the respective experimental diets for the remaining period (41 days). The average daily DM feed intake, weight gain and feed efficiency was calculated accordingly. No significant differences in DMI, ADG and the efficiency with which ingested feed were utilized (FCR), were recorded for the treatments. However, the addition of unsaturated soybean oil to the diet significantly increased the efficiency with which the ME of the diet was utilized. In contrast with the natural antioxidant, the inclusion of unsaturated soybean oil in the diet containing a synthetic antioxidant, resulted in a significant lower MEI by the lambs - indicating that a lipid x antioxidant interaction occurred. Results of the present study seem to indicate that dietary lipid saturation in the finishing diets of lambs had no influence on their growth performance. However, a more efficient utilisation of ME in the finishing diet containing unsaturated soybean oil, compared to the saturated beef tallow, did occur.


Booyens K.E.,Wildlife and Grassland science | Einkamerer O.B.,Wildlife and Grassland science | van der Merwe H.J.,Wildlife and Grassland science | Hugo A.,University of the Free State | And 2 more authors.
South African Journal of Animal Sciences | Year: 2013

The influence of a synthetic or natural antioxidant and lipid saturation on the apparent digestibility of nutrients in a standard lamb finishing diet was investigated. The four dietary treatments consisted of the same basal diet, providing 187 g CP-, 355 g NDF- and 71 g EE per kg DM, but differing in supplemental lipid source (30 g/kg of either saturated beef tallow or unsaturated soybean oil) and type of antioxidant included (125 g/ton of either a synthetic or natural antioxidant). The digestibility study was conducted over a period of 12 days (including a 4-day adaptation to the faecal collection bags). Twenty-eight S.A. Mutton Merino lambs (45.1 ± 3.0 kg) were randomly allocated to the four dietary treatments (n = 7 lambs/treatment). Composite feed, feed refusal and faecal samples of individually penned lambs were collected for chemical analysis. The apparent digestibility coefficients, digestible nutrient and available energy content were calculated accordingly. The DMI of the lambs did not differ significantly between the various experimental diets. The inclusion of unsaturated soybean oil reduced the apparent digestibility of NDF in the diet. The apparent digestibility of NDF seems to be higher when a natural antioxidant was included in the diet. The comparatively negative effects of the unsaturated lipid source and synthetic antioxidant on the apparent digestibility of NDF were associated with a significantly lower digestible NDF content in the experimental diet. Accordingly, soybean oil resulted in a significantly lower ME content in the diet. However, estimating ME from DE with a constant factor of 0.8 probably underestimates the ME content of diets supplemented with lipids rich in unsaturated fatty acids. The latter are known to reduce methane production, and hence, energy losses.

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