| Titles |
|
English :
|
Effect of protected proteins on the milk yield." Influence of protecting cotton seed and soyabean proteins by either heat or formaldehyde treatments on some metabolic and performance traits of Friesian cows”
|
|
Arabic :
|
تأثير البروتينات المحمية على انتاج اللبن "تأثير حماية كسب بذرة القطن و كسب فول الصويا بالمعاملات الحرارية او الفورمالدهيد على بعض خصائص التمثيل الغذائى و الاداء الانتاجى لابقار الفريزيان
|
|
| Abstract |
The experimental part of this study was conducted in the Egyptian Company for Meat & Milk Production, Faraskour Sector, Station No.7 during 1997. The analytical work was performed in the Laboratories of Animal Production Department, Faculty of Agriculture, Mansoura university.
The work was aimed to investigate the effects of protecting either UCSM or SBM proteins from degradation in the rumen by heat or formaldehyde treatments on the performance of moderately high producing Friesian cows (20 kg milk/day) in terms of milk production and its composition as a consequence of their utilization of diets containing such proteins.
Thirty-six lactating Friesian cows in peak lactation were used in a 2 x 3 factorial experiment including 2 sources of protein; undecorticated cotton seed meal (UCSM) and soybean meal (SBM) and 3 protection methods; untreated (U, control), heat-treatment (H) and formaldehyde treatment (F). The experimental cows were assigned to six balanced groups (6 cows each) for body weight, initial milk yield, calving date and parity.
Six diets were formulated from green berseem (GB), rice straw (RS) and concentrate feed mixture (CFM) in the following formulas:
1. GB + RS + U-UCSM.
2. GB + RS + H-UCSM.
3. GB + RS + F-UCSM.
4. GB + RS + U-SBM.
5. GB + RS + H-SBM.
6. GB + RS + F-SBM.
The daily allowances of feed intake were adjusted every 15 days according to body weight, milk yield and fat percentage. The experiment was carried out from weeks 7 to 22 of lactation. Cows were housed in a
free-stall barn and fed in groups. Cows were milked twice daily at 5.0 a.m. and 5.0 p.m. and the individual morning and evening milk yields were recorded daily. Milk samples were obtained each 15 days from each cow for two consecutive milkings and were analyzed for fat, protein, lactose, solids not-fat and total solids by the Milk Scan.
Digestibilities and feeding values of the tested diets were determined by the use of acid insoluble ash (AlA) as an internal marker.
Blood samples were collected biweekly from all animals for urea N, total protein, albumin, globulin and creatinine determination just before offering the morning meal and 4 hours post-feeding.
Ruminal fluid samples were taken via stomach tube from three cows in each treatment on week 13 of the experimental period just before offering the morning meal and 4 hours post-feeding for determination of pH, NH3-N and VFA.
Data were statistically analyzed by the analysis of variance method. Duncan's multiple range test was used for comparison among means at 0.05 level.
The results of this study could be summarized as follows:
1.Milk yield was increased as a result of treating both dietary protein
supplements (UCSM &SBM) by either heat or formaldehyde. Therefore, the consumed dry matter, organic matter and rumen undegaradable protein were increased for cows fed diets containing protected protein than those fed diets containing unprotected protein.
2. Digestibilities of OM, CF and NFE were higher in diets containing UCSM than those containing SBM.
3. Although digestibility values of CP were significantly (P<0.0I) higher for diets containing protected proteins by heat or formaldehyde (77 .32 and 77.72%, respectively) than diets without protected protein (75.92%). Yet the numerical values were close and did not exceed 1.8 percentage units indicating that neither formaldehyde nor heat treatments had deleterious effect on treated proteins.
4. The improvements in the digestibilities of most nutrients reflected better feeding values in terms of DCP for diets containing treated proteins than the control.
5. Ruminal pH and NH)-N values were higher (P<0.0I) for cows fed on diets containing UCSM than those fed SBM.
6. Ruminal NH)-N concentrations decreased by 15.4% in diets treated with heat or by 12.8% for diets treated with formaldehyde compared with those of untreated diets, indicating efficiency of the protection and / or better synchronization between availability of energy and release of NH3).
7. Milk yield and 4% FCM were improved (P<0.0I) by 11.1 and 11.9% (on average), respectively for cows fed protected protein than those fed unprotected protein.
8. The yield of milk fat, protein, lactose, solids not-fat and total solids (kg/day) were improved (P<0.0I) by 0.09,0.07,0.11,0.20 and 0.29, respectively for cows fed protected protein than those fed unprotected protein.
9. Cows receiving diets containing protected protein were more persistent for milk production and its components during the experimental period than those receiving the untreated proteins.
10. Milk yield per unit of DM or CP intakes and efficiency of protein utilization for milk yield were better for cows given protected protein either by heat or formaldehyde than those fed unprotected protein.
II. Milk yield was increased in response to increased intake of undegradable-CP.
12. The concentration of plasma urea-N was lower (P<0.0l) in cows fed treated proteins by heat or formaldehyde than untreated materials, indicating once more better utilization of protected proteins.
13. The protected protein diets by heat or formaldehyde resulted in the highest (P<0.0l) plasma total protein, albumin and globulin concentrations.
14. The change in body weight during the experimental period was significantly (P<0.05) less for cows fed on diets containing protected protein by either heat or formaldehyde treated than for those fed on diets without protected protein.
It could be concluded on the basis of the results of this study that UCSM is a better source of protein than SBM in formulating diets of lactating cows, based on better fermentation characteristics in the rumen and improved feeding values. In addition, utilization of UCSM or SBM may be improved by heat or formaldehyde treatment as indicated by increasing efficiency of protein utilization for milk production specially for high yields (>20 kg/day) when microbial protein synthesized in the rumen together with the proportion of dietary and protected dietary protein which escapes degradation in the rumen are not sufficient to supply the host animal with its requirements for such high production. Both heat and formaldehyde treatments could be recommended to improve milk yield and its components. Also, it appears that heat or formaldehyde are suitable for protection without appreciably affecting rumen microflora, pattern of rumen fermentation and enzymatic digestion of protein.
Since both heat and formaldehyde treatments were almost equally effective in protecting the proteins of UCSM and SBM, the preference should be given to the applicable and the more economic basis. Heat treatment cost energy expenditure, however formalin could not be absolutely recommended before establishing and developing an accurate and precise method of estimating formalin in the produced milk for the sake of ensuring health safety of humans.
|
| Publication year |
2000
|
| Pages |
PP. 128
|
| Availability location |
مكتبة معهد بحوث الانتاج الحيوانى-شارع نادى الصيد- الدقى - الجيزة
|
| Availability number |
688
|
| Organization Name |
Animal Production Research Institute (APRI)
|
| Country |
Egypt
|
| Author(s) from ARC |
|
| Agris Categories |
Animal feeding
|
AGROVOC
TERMS |
Cottonseed.
Cows.
Formaldehyde.
Heat.
Metabolism.
Milk yield.
Performance testing.
Proteins.
Soybeans.
|
| Proposed Agrovoc |
protected proteins;
|
| Publication Type |
PhD Thesis
|