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Effect of By-Pass Cement Dust Supplementation Level to Diets on the Productive Performance of Lactating Buffaloes



M.E.H. Shalabi , S.M. Kholif and M.M. Khorshed
 
ABSTRACT

Fifteen lactating buffaloes after seven days post-parturition were divided randomly into three groups (of 5 animals each) to study the effect of adding By-Pass Cement Dust (BCD) level to the buffalo’s diets on the coefficients of nutrient digestibility and milk yield and composition using complete random block design experiment with 90 days period. The control group was given a basic diet consisting of (60% Concentrate Feed Mixture (CFM): 20% berseem clover: 20% rice straw), the second and third groups were fed the control ration plus 7.5 and 15 g/head/day BCD, respectively. The CFM for each animal was offered individually once daily at 8.00 am, while berseem clover and rice straw were offered at 10.00 am. Individual milk samples were collected every two weeks of the experimental period for chemical analysis. After 4 h of the morning meal, grab samples and blood serum samples were collected in the last day every month for chemical analysis. Nutrients digestibility coefficient of organic matter, crude protein and crude fiber were significantly higher with animals fed low level followed by high level of BCD and then control. Also, dry matter, ether extract and nitrogen free extract digestibilities followed the same trend while the effects of treatments failed to be significant. Supplementation of low level of BCD to buffaloes rations increased yields of milk (p<0.05), 4% FCM (p>0.05) and milk constituents (p>0.05) compared with other treatments. Milk fat, protein and lactose contents were insignificantly increased with animals fed BCD compared with control. While, total solids, ash and solids not fat contents were not differed among treatments. Milk P, Mg and K contents were significantly higher with animals fed BCD compared with control. Feed efficiency as Milk yield/dry matter intake (DMI) (p<0.05) and FCM/DMI (p>0.05) were higher for animals fed BCD than that fed control. Blood serum total protein, urea and glucose were higher (p<0.05) in animals fed on low BCD supplemented rations, while, other blood serum parameters were not affected by treatments. Also, blood serum Ca, Na and Fe were significantly higher in animals fed on low BCD supplemented rations compared with control. It could be concluded that low BCD supplementation (7.5/head/day) to diets improved nutrients digestibility coefficients, milk yield and milk constituents than other treatments.

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M.E.H. Shalabi , S.M. Kholif and M.M. Khorshed , 2007. Effect of By-Pass Cement Dust Supplementation Level to Diets on the Productive Performance of Lactating Buffaloes. International Journal of Dairy Science, 2: 321-329.

DOI: 10.3923/ijds.2007.321.329

URL: https://scialert.net/abstract/?doi=ijds.2007.321.329

INTRODUCTION

Late stages of gestation and early lactation contribute to changes in both Ca and P metabolism (Liesegang et al., 2000). Increased bone resorption occurs because of skeletal mineralization of the fetus in late gestation and milk production during early lactation (Brommage and DeLuca, 1985; Fukuda and Iida, 1993). Milk production requires an available supply of P and bone resorption was estimated to supply 500-600 g of P during the first few weeks of lactation (Wu et al., 2000). A large portion of P mobilized from bone tissue may be a direct consequence of Ca mobilization for Ca homeostasis in early lactation (Horst, 1986; Wu et al., 2000). It is hypothesized that feeding a prepartum ration to supply between 30 and 35 g of P/cow daily for multiparous Holstein cows is sufficient to meet periparturient requirements without adverse effects on metabolism or early lactation performance (Peterson et al., 2005). Overfeeding of P is costly and increases the risk of environmental damage through eutrophication of lakes and streams (Rotz et al., 2002). Once the P requirements of the cow are met, most excess dietary P is excreted in the manure, primarily in the feces (Wu et al., 2000, 2001). The term micro-or trace minerals refers to those specific elements that are present in small amounts in the diet and are needed in small amounts by the body (Segerson et al., 1977; Corah, 1996). Due to this definition, trace minerals are sometimes ignored or overlooked. Nevertheless, they participate in a wide range of body functions, most of them as components of important enzymatic systems that involve immune, metabolic and reproductive functions (Graham, 1991; Ferguson, 1996; NRC, 2001).

This study was conducted to evaluate the effects of supplementation level of BCD-as high source of calcium, phosphorous, sodium and iron contents-to rations on the productive performance of lactating buffaloes.

MATERIALS AND METHODS

This study was conducted at the Experimental Farm in Shalakan, Faculty of Agriculture, Ain Shams University and Dairy Science Department, National Research Center, Dokki, Giza, Egypt, during 2005.

By-Pass Cement Dust
By pass Cement Dust was obtained from National Cement Company (El-Tabbin, Helwan, Egypt). X-ray analysis of by-pass cement dust is shown in Fig. 1, from this figure it was shown the main fraction components of BCD are calcite (calcium carbonate (CaCO3)), quartz (SiO2), sodium chloride (NaCl).

Animals and Diets
Fifteen lactating buffaloes after seven days of parturition were divided randomly into three groups (of 5 animals each)-according to milk production and lactation season-to study the effect of supplementation level of BCD to buffalo’s rations on nutrient digestibility coefficients, blood serum parameters and milk yield and composition using complete random block design experiment with 90 days period. Experimental rations were control (60% Concentrate Feed Mixture (CFM): 20% berseem clover: 20% rice straw), treatment I (control ration plus 7.5 g/head/day BCD) and treatment II (control ration plus 15 g/head/day BCD).

Fig. 1: X-ray analysis of by-pass cement dust

Table 1: Chemical composition of dietary ingredients (% DM basis)
CFM: Concentrate Feed Mixture, RS: Rice Straw, BC: Berseem Clover, BCD: By-pass Cement Dust

The CFM was consisted of 35% yellow corn, 25% wheat bran, 22% decorticated cotton seed meal, 15% rice bran, 1.5% ground limestone and 1.5% common salt. The chemical composition of ingredients is showed in Table 1. The offered feeds were assessed to cover the requirements for each animal (ARC, 1965). The CFM for each animal was offered individually once daily at 8.00 am, while berseem clover and rice straw were offered at 10.00 am and 4.00 pm. Dry matter intake was measured during the last refusals of the previous day. Clean water was available to animals at all times.

Analysis of Feed Samples
Samples of ingredients and rations were analyzed for DM, ash, CF and Ether Extract (EE) according to methods of AOAC (1995). While, organic matter and Nitrogen-Free Extract (NFE) was calculated. Calcium, potassium, magnesium, iron and sodium were analyzed by using atomic absorption spectrophotometer (IL-5-12) according to Jackson (1958). While, inorganic phosphorous was determined by calorimetric method by using kits according to Troug and Meyer (1939).

Digestibility Trial
Simultaneously three digestibility trials were carried out on all animals of each treatment of feeding trail and repeated each 30 days of the experimental period. Grab sample method was used and silica as internal marker was applied for determining the digestibility. After 4 h of the morning meal, feces grab samples were collected individually from each animal for three successive days. Solution of 10% H2SO4 were added to the representative samples then dried in oven at 70°C for 24 h. The dried feces samples from each animal were mixed and stored at 18°C for chemical analysis. The digestibility coefficient was calculated according to the following formula according to (Gallup et al., 1945; Forbes and Garrigus, 1948).

Sampling and Analysis of Milk
Individually milk samples were collected every two weeks of the experimental period (90 days). The buffaloes were hand milked (twice/day), milk yield was recorded and pH of milk was determined (Ling, 1963). Milk samples were also, analyzed for fat, Total Solids (TS), Total Protein (TP) and ash (Ling, 1963), however, lactose was colorimetric determined according to Barnett and Abd El-Tawab (1957). Solids-Not-Fat (SNF) was calculated by difference.

Sampling and Analysis of Blood Serum
Blood samples were collected from the jugular vein of each animals at the last day of each period after 4 h post morning feeding. The collected blood samples were centrifuged at 4000 r.p.m./20 min. to separate the serum. The obtained serum was stored at 18°C till it was analyzed. Serum total protein was determined as described by Armstrong and Carr (1964), albumin (Doumas et al., 1971), urea (Patton and Crouch, 1977), glucose (Siest et al., 1981) and serum GOT and GPT (Reitman and Frankel, 1957). Globulin and albumin/globulin ratio were calculated.

Statistical Analysis
Data obtained from this study were statistically analyzed according to procedures outlined by Snedecor and Cochran (1982). The procedure was complete random block design for milk, blood and digestibility data using the general linear model procedure:

Yijk = μ+ Ri + Tk + eijk

Where Yijk is the parameter under analysis of the ijk goat, μ is the overall mean, Ri is the effect due to the lactation period on the parameter under analysis, Tk is the effect due to treatment on the parameter under analysis, eijk is the experimental error for ijk on the observation.

The Duncan's multiple range test was used to test the significance between means (Duncan, 1955).

RESULTS AND DISCUSSION

Dry Matter Intake
Dry matter intake did not differed among treatments, being 15.14, 15.08 and 14.85 kg/head/day in control, low and high BCD, respectively (Table 2). The animals of BCD treated group consumed lower (p>0.05) amount of dry matter than control animals. Calcium, phosphorous and iron intake were increased significantly (p<0.05) with increasing BCD level in the buffaloes diets. These results may be due to high concentrations of calcium, phosphorous and iron in the BCD. While, magnesium, sodium and potassium intake were slightly increased with adding BCD. The P content of the recommended diet corresponded closely to what the National Research Council (NRC, 2001) considers to be the requirement for lactating cows with milk production slightly lower to that of buffaloes used in this experiment. Our results suggest that the true digestibility and availability of P in feeds or BCD is lower than the value of 70% used by NRC (2001).

Nutrients Digestibility Coefficient
Nutrients digestibility coefficient as affected by experimental treatments are shown in Table 3. Organic matter, crude protein and crude fiber digestibilities were highly increased (p<0.05) with animals fed ration supplemented with low level of BCD followed by high level of BCD and then control.

Table 2: Nutrients and minerals intake of lactating buffaloes fed on experimental rations
a, b, c means with different superscripts are significantly different (p<0.05)

Table 3: Nutrients digestibility coefficients of lactating buffaloes fed on experimental rations
Each value is mean of 27 samples for 9 animals. a, b, c means with different superscripts are significantly different (p<0.05)

Table 4: Milk yield and composition and feed efficiency of lactating buffaloes fed on experimental rations
Each value is mean of 54 samples for 9 animals. A,B,C and a,b,c means with different superscripts are significantly different (p<0.01) and (p<0.05)

The same trend is true for milk yield (p<0.05) and yields of fat and milk composition as g/d percentage (p>0.05) (Table 4) or blood serum albumin, P, K and Mg (p>0.05) (Table 5). Also, digestibility of dry matter, ether extract and nitrogen free extract were followed the same trend, however, the effect of treatments failed to be significant. This improvements of nutrients digestibility may be due to the availability of minerals in the rumen lead to the increase of the numbers of rumen total viable bacteria and cellulolytic bacteria with animals fed BCD. In total, the addition of low BCD level resulted a good nutrients digestibility coefficient while, the high level of BCD resulted a negative results.

Milk Yield and Composition
Data of milk and milk constituent yields of the experimental buffaloes are summarized in Table 4. Milk yield (p<0.05) and 4% FCM (p>0.05) were higher in low level followed by high level of BCD supplemented groups than buffaloes receiving control. The higher milk yield with the animals fed low level of BCD supplemented ration might be attributed to the positive effect of BCD on the digestibility of organic matter and its nutrients as shown in Table 3. Lopez et al. (2004) and Peterson et al. (2005) were reported that high P supplementation to lactating cows diet was not affected milk yield. As an impact of the increased milk yield, daily fat, protein, lactose, solids not fat and ash yields were insignificantly higher in groups received low level of BCD than that received other treatments. While, milk total solids yield was slightly decreased with animals fed the low level of BCD compared with animals fed other rations.

Data of milk composition are also summarized in Table 4. Milk protein content was higher (p>0.05) in T2 (low level of BCD) than other treatments. Milk casein nitrogen was increased with animals fed ration added with BCD compared with control animal. Calcium and phosphorous were involved in casein synthesis in the mammary gland which led to the increase of milk protein with animals fed ration supplemented with low level of BCD. Supplementation of BCD increased (p>0.05) milk lactose content, these results probably attributed to the higher (p<0.05) of crude fiber digestibility (Table 3) and blood serum glucose (p<0.05) and albumin (p>0.05) concentration of animals fed low level of BCD supplemented ration as shown in Table 5. It led to an increase in milk lactose synthesis and consequently milk production being increase. Milk fat content was insignificantly increased with low level of BCD treated groups compared with control. However, milk total solids, solids not fat and ash contents and milk pH values were not differ among treatments.

Milk composition was not affected by dietary Ca and P contents. There is no evidence in the literature suggesting that fat content of milk is influenced by feeding Ca and P in excess of NRC (2001) requirements. There have been reports of reduced protein content of milk with low dietary P (De Boer et al., 1981; Call et al., 1987; Wu and Satter, 2000), but the majority of studies (Valk and Sebek, 1999; Wu et al., 2000, 2001) have shown no difference in concentration of milk protein due to dietary P content. Since Ca and P are part of the casein micelle (Jenness, 1985), blood serum Ca and P concentrations could influence milk protein content.

Milk P was increased (p<0.01) while, milk Ca was slightly decreased with animals fed BCD compared with control. In the preset study, milk Ca concentration was lower than that of Gowenlock et al. (1988) who suggested that milk Ca concentration ranged from 160 to 1600 m gL-1 for normal animal growth. This results indicate the higher P absorption than Ca from blood to mammary gland for milk protein synthesis. Calcium has a very close inter-relationship with P and vitamin D. Optimum animal performance is linked closely with Ca and P level in the diet (Hegsted, 1973). The homeostatic mechanism of animals tends to protect against the absorption of excessive quantities of the elements, thus eliminating extra through faeces (Table 6). This may be due to its relationship between Ca and other nutrients, especially P; the feeding of excessive levels of Ca for an extended period of time may have detrimental effects on animal performance.

Milk Mg and Na were significantly higher (p<0.05) with animals fed BCD than control. However, milk Fe and K were not affected by treatments. Results obtained here are in harmony with those found by Gowenlock et al. (1988) who reported that milk K and Fe concentrations ranged from 350-700 and 0.5-3.0 m gL-1, respectively, for normal animal growth. Excessive level of K may interfere with the uptake of other minerals, including Mg and P. The absorption of Fe is facilitated by the presence of vitamin C and Ca (Ashraf et al., 2006).

Generally, feed efficiency calculated as milk yield/DMI (p<0.05) and 4% FCM/DMI (p>0.05) were improved with animals fed BCD supplemented ration compared with control.

Blood Serum Metabolites
Data in Table 5 showed no significant differences among different treatments on some blood serum parameters, except urea and glucose values, which were increased (p<0.05) with animals fed low level of BCD compared with other treatments. Also, blood serum total protein was higher (p<0.05) with animals fed high level of BCD than control. These results may be due to the improvements occurred in metabolic process as a BCD response. Diets containing BCD tend to decrease GOT, GPT and A/G ratio however, concentrations of albumin and globulin were slightly increased with animals fed BCD. Serum glucose had the same trend of milk yield Table 4 which was in accordance with the results of Clark et al. (1977) who noted a positive correlation between blood glucose and milk yield.

Blood serum Ca was increased (p<0.05), however, concentrations of serum P was decreased with animals fed low level followed by high level of BCD and then control. Our results were lower than that obtained by Gowenlock et al. (1988) who noted that blood Ca concentration ranged from 50-150 m gL-1 for normal animal growth. Goff (1998) found that blood serum P concentration was within the normal range (4-8 mg dL-1) for adult ruminants. Blood serum sodium and iron concentrations were higher (p<0.05) with animals fed BCD than that of control, however, magnesium and potassium were not significantly affected by treatments. Gowenlock et al. (1988) reported that blood K and Fe concentrations ranged from 100-250 and 1.5-3.0 mg L-1, respectively, for normal animal growth.

In the present study, high faecal minerals concentrations with animals fed BCD (Table 6) showed that minerals were not absorbed properly due to inefficient metabolic system of the animals having deficiencies of other major elements necessary for proper functioning of the metabolic systems. Faecal Ca, K and Fe concentrations ranged from 2000-6000, 1000-3000 and 200-236 mg L-1, respectively, for normal animal growth (Gowenlock et al., 1988). There is no evidence in this experiment that feeding minerals in excess of the NRC (2001) requirement affects the incidence of health problems.

Table 5: Blood serum parameters of lactating buffaloes fed on experimental rations
Each value is mean of 27 samples for 9 animals. a,b,c means with different superscripts are significantly different (p<0.05)

Table 6: Minerals concentrations (mg dL-1) of faeces of lactating buffaloes fed on experimental rations
Each value is mean of 27 samples for 9 animals. a,b,c means with different superscripts are significantly different (p<0.05)

CONCLUSIONS

It could be concluded that supplementing buffaloes’ ration with 7.5 g/head/day of By-pass Cement Dust (BCD) was improved nutrients digestibility coefficients, feed efficiency and milk production with no deleterious effect on general health of animals fed BCD as compared to animals fed the control ration.

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