- Email: [email protected]
Effects of whole cottonseeds on milk yield, milk composition, and blood components of dairy cows in hot weather
ELSEVIER
Animal Feed Science and Technology 52 ( 1995) 227-235
Effects of whole cottonseeds on milk yield, milk composition, and blood components of dairy cows in hot weather N.G. Belibasakis”,*, D. Tsirgogiannib “Department ofAnimal Husbandry, Faculty of Veterinary Medicine, Aristotelian University of Thessaloniki, Thessaloniki, Greece bGeneral Hospital ‘Agios Pavlos’of Thessaloniki, Thessaloniki, Greece Received 8 April 1994; accepted 7 September 1994
Abstract Sixteen multiparous Friesian cows, 70- 140 days post partum, were allotted to two groups of eight cows, according to calving date, lactation number and daily yield, and assigned randomly to one of two diets in a crossover design experiment. The two experimental diets were concentrate, containing either 20% whole cottonseeds and 13% soya bean meal or 14% cottonseed meal and 18.5% soya bean meal, plus a mixture of maize silage and straw in the proportions 8: 1 (fresh weight) ad libitum. The concentrate was offered individually, in two equal meals daily at 0.4 kg kg - I of milk produced, and the mixture of maize silage and straw was offered ad libitum once daily on a group basis. The experimental period lasted from 10 June to 4 August 1993, and the cows were housed in an open lot. Dry matter intake, milk protein content and yield, as well as content of milk lactose, total solids and solids not fat were not significantly affected by the diet. In contrast, whole cottonseeds supplementation increased actual milk yield (25.1 vs. 23.1 kg day-‘; PC 0.05), 4% fat-corrected milk yield (25.0 vs. 21.5 kg day-‘; PC 0.05), milk fat content (3.98 vs. 3.56%; P~0.05) and milk fat yield (1.0 vs. 0.82 kgday-‘; P~0.05). No significant differences were observed in blood plasma concentrations of glucose, total protein, urea, sodium, potassium, calcium, phosphorus and magnesium. In contrast, increased concentrations in plasma of triglycerides ( 18.8 vs. 15.9 mg ( 100 ml)-‘; P-c 0.05), cholesterol (225.1 vs. 173.2 mg (100 ml)-‘; P
* Corresponding
Lactation performance
author.
0377-8401/95/$09.50 0 1995 Elsevier Science B.V. All rights reserved SSDI 0377-8401(94)00725-X
228 N.G. Belibasakis, D. Tsirgogianni /Animal Feed Science and Technology 52 (1995) 227-235
1. Introduction In summer, as temperature rises above the upper critical temperature of 25°C for Holstein Friesian cows (Berman et al., 1985 ), high-producing dairy cows often fail to consume sufficient feed (Collier et al., 1982), particularly of roughage rather than concentrate (McDowell, 1972)) to meet their nutrient requirements, especially energy. Formulating diets with supplemental fat has been advocated as a possible means of reducing heat stress on lactating cows, owing to their high energy content and low heat increment of fat relative to other nutrients (Beede and Collier, 1986). Skaar et al. ( 1989) found that cows calving during warm season months (2 April- 1 August) and consuming diets supplemented with 5% fat produced more milk than herdmates not receiving fat, but milk composition was not affected by treatment. Knapp and Grummer ( 199 1) reported that adding 5% fat to diets for cows during hot weather increased milk fat content, but milk yield and milk protein content and yield were not affected. The addition of whole cottonseeds (WCS) to diets for lactating cows during hot weather could be beneficial for milk production. This is because WCS is a rich source of fat, protein and fibre to improve the energy, protein and libre balance of dairy cows. Fat in WCS is encapsulated by a seed coat that may limit the nutritional problems for cows given large amounts of fat. Also, Holter et al. ( 1992) reported that addition of 15% WCS to diets for lactating cows reduced total heat production by 6% and reduced heat in excess of maintenance by 8%. The objectives of this experiment were to evaluate effects of WCS in a concentrate diet containing either 20% WCS and 13% soya bean meal or 14% cottonseed meal and 18.5% soya bean meal, plus a mixture of maize silage and straw, on milk yield, milk composition, dry matter intake, body condition score, and blood plasma metabolites and electrolytes of lactating cows during hot weather.
2. Materials and methods 2.1. Experimental animalsand diets Sixteen multiparous Friesian cows, 70-140 days post pat-turn, weighing approximately 600 kg at the beginning of experiment, were allotted according to calving.date, lactation number and daily milk yield into two groups of eight cows each, and assigned randomly to one of two diets in a crossover design experiment (Cochran and Cox, 1957 ). The two experimental diets were concentrate containing 0% or 20% WCS (fresh weight ) plus a mixture of maize silage and straw in the proportions 8: 1 (fresh weight) ad libitum. Chemical composition of concentrate mixtures, maize silage and straw, and the ingredients of concentrate mixtures, are shown in Table 1. The cows remained on trial for 11 weeks, from 20 May to 4 August 1993. The first 3 weeks were the
N.G. Belibasakis, D. Tsirgogianni /Animal Feed Science and Technology 52 (1995) 227-235 229 Table 1 Chemical composition trate mixtures (O/o) Parameter
Chemical analysis2 Dry matter Crude protein Ether extract Crude fibre Neutral detergent fibre ME3 (MJ kg-‘) Ingredients 4 Ground maize Barley Soya bean meal Maize gluten meal Cottonseed meal Whole cottonseeds Dicalcium phosphate Calcium carbonate’ Magnesium oxide5 Mineral-vitamin mix Salt Total
of concentrate
mixtures, maize silage and straw, and ingredients
Concentrate Control
WCS’
81.4 24.3 3.2 6.3 14.9 13.0
87.5 24.3 6.3 6.2 14.3 13.3
39.5 12.3 18.5 11.3 14.0
37.0 12.0 13.0 12.5
0.4 2.0 1.0 1.0 100.0
of concen-
Maize silage
Straw
30.2 8.3 3.1 26.8 50.7 9.6
90. I 4.5 1.5 42.4 75.2 7.1
20.0 1.0 2.3 0.2 1.0 1.0 100.0
‘WCS-Whole cottonseeds. ‘Dry matter basis except dry matter. 3Metabolizable energy calculated according to the National Research Council ( 1988). Energy values are expressed in megajoules on the assumption that 1 Meal is equivalent to 4. I84 MJ. “Fresh weight basis. ‘Amounts of Ca and Mg in WCS diet were adjusted above those in the control diet, because added fat increases Ca and Mg soap formation in the rumen and the excretion of these elements in the faeces (National Research Council, 1988).
adjustment period, and the following 8 weeks included two experimental periods of 4 weeks each. During the adjustment period, all cows were given the concentrate mixture without WCS (control diet) plus the mixture of maize silage and straw. During the first experimental period ( 10 June-7 July) one group of cows was fed on the control diet and the other group on the diet with WCS. During the second experimental period (8 July-4 August) the cows were changed to the other diet. The concentrate was offered individually, in tie-stalls, in two equal meals daily at 0.4 kg kg-’ milk produced. Concentrate refusals were removed when the cows left the tie-stalls. Concentrate allowances were adjusted weekly on the previous week’s milk production. The mixture of maize silage and straw was offered ad libitum
230 N.G. Belibasakis, D. Tsirgogianni /Animal FeedScience and Technology 52 (1995) 227-235
once daily on a group basis. Silage and straw refusals were removed daily and weighed. The two groups of cows were housed in an open lot. Twice daily, at 06:OOand 17:OOh, the cows were brought into the tie-stalls for milking and feeding. Water was available to the cows at all times in the open lot area. Body condition score of cows was measured on a system with l-5 scale on the first and last day of each experimental period (Lowman et al., 1976). 2.2. Sample collection and analyses Milk yield was recorded for all animals at each milking during the last 2 weeks of each experimental period. Milk samples were taken at each milking during the last 3 days of each period and analysed for total solids (TS ) , fat, solids-not-fat (SNF), crude protein (CP ), and lactose using a milk analyser (Milco Scan 104 A/s, N. Foss Electric, Hillerod). Samples of maize silage and straw were taken weekly and samples of concentrate mixtures were taken while mixing. The samples of feed were analysed for dry matter (DM ), CP, crude fibre (CF), and ether extract (EE) according to the Association of Official Analytical Chemists (1975), and for neutral detergent fibre (NDF) as described by Van Soest and Robertson ( 1980). Blood samples were drawn from the tail vein into heparinized tubes on the last day of each experimental period, at about 4 h after feeding, and centrifuged. Plasma was stored at -20°C until analysed for glucose, total protein, urea, triglycerides, cholesterol, phospholipids, Na, K, Ca, P and M, using a DuPont Dimension automated clinical chemistry analyser validated for bovine samples (DuPont Dimension 380, Wilmington, DE). 2.3. Statistical analysis Milk yield, milk composition, dry matter intake (DMI) of concentrates, body condition score and blood plasma components data were tested by analysis of variance with two factors using the Minitab Statistical Package (Ryan et al., 1985 ) . The model contained effects of cow, period and diet. Effects were considered significantly different at P-C0.05.
3. Results and discussion In the Cotton and Industrial Plants Institute (CIPI), which is about 2.5 km from the experimental dairy farm, the average maximum temperature during the experimental periods was 32.7’ C (SE 0.36’ C ). The weekly air temperature and relative humidity during the experimental periods according to CIPI records are shown in Table 2.
N.G. Belibasakis, D. Tsirgogianni /Animal Feed Science and Technology 52 (1995) 227-235 23 1 Table 2 Average weekly air temperature August 1993)’ Date
IO-16 June 17-23 June 24-30 June 1-7 July 8-14 July 15-2 1 July 22-28 July 29 July-4 August
and relative humidity during the experimental
Temperature
( “C)
periods ( 10 June-4
Relative humidity (%)
Maximum
Minimum
OS:00 h
14:OOh
31.9 30.4 31.0 34.0 33.0 32.4 32.4 34.4
26.2 20.6 22.6 25.0 20.6 23.6 22.2 25.4
72.0 56.0 52.0 54.2 51.4 59.0 57.6 54.6
51.0 41.0 44.0 36.0 36.0 48.0 34.0 39.0
‘Records of the Cotton and Industrial Plants Institute, Sindos Thessaloniki, Greece.
3.1. Feed intake Mean daily DMI, metabolizable energy intake and crude protein intake (Table 3 ) were unaffected by treatment during hot weather. Daily feed DMI was not affected by the addition of WCS from 0% to 20% of the diets for lactating cows (Coppock et al. 1985; DePeters et al., 1985; Homer et al., 1986). However, when WCS increased to 30% of the diets the DMI decreased significantly (Coppock et al., 1985). 3.2. Milk yield and composition Mean daily milk yield and 4% fat-corrected milk (Table 3 ) were 2 kg day- ’ and 3.5 kg day-’ higher, respectively, with the WCS diet; the differences were significant (P< 0.05 ). Also, milk fat content and yield (Table 3) were higher by 0.42 percentage units and 180 g day-’ (P
232 N.G. Belibasakis, D. Tsirgogianni /Animal Feed Science and Technology 52 (1995) 227-235 Table 3 Average dry matter intake, milk production and composition
on the two diets
Diets
Dry matter intake (kg day-‘) Total Concentrate Maize silage-straw mixture Metabolizable energy intake (MJ day-’ ) Crude protein intake (kg day-’ ) Milk production (kg day-’ ) Actual milk yield 4% FCM’ yield Fat yield Protein yield Milk composition (%) Total solids Fat SNF’ Protein Lactose Body condition score
Control
WCS’
17.3 7.9 9.4 186.5 2.6
17.4 8.1 9.3 190.6 2.6
SED
Level of significance
0.42
NS
23.1 21.5 0.82 0.71
25.1 25.0 1.0 0.76
0.97 1.27 0.07 0.04
* * * NS
11.74 3.56 8.18 3.06 4.41 2.98
12.11 3.98 8.13 3.04 4.39 3.11
0.28 0.17 0.13 0.10 0.09 0.07
NS * NS NS NS NS
‘WCS-Whole cottonseeds. 2FCM-Fat-corrected milk. 3SNF-Solids not fat. *P-C 0.05; NS, not significant.
straw significantly increased actual milk yield, 4% fat-corrected milk yield, and milk fat content and yield of the cows during hot weather. Milk protein content and yield (Table 3 ) were not significantly affected by the addition of WCS to the diet. Similar results have been reported by Skaar et al. ( 1989), and Knapp and Grummer ( 1991) when 5% fat was added to diets of lactating cows during hot weather. Also, Ferguson et al. ( 1990) and Holter et al. ( 1992) found no change in milk protein content by the addition of 3-9% fat and 15% WCS, respectively, to diets of lactating cows. However, other studies showed a decrease of milk protein content with the addition of WCS to diets for lactating cows (Smith et al., 1981; DePeters et al., 1985; Horner et al., 1986; Wilks et al., 199 1; Smith et al., 1993). Milk lactose, TS and SNF content (Table 3 ) were not significantly affected by the WCS diet. 3.3. Body condition score Body condition score (Table 3) was not significantly affected by the addition of WCS to diets for dairy cows during hot weather.
N.G. Belibasakis, D. Tsirgogianni /Animal Feed Science and Technology 52 (1995) 227-235 233
3.4. Blood plasma components
Blood plasma glucose, total protein, urea, Na, K, Ca, P and Mg concentrations (Table 4) were not significantly affected by the addition of WCS to the diet of cows. Coppock et al. ( 1985 ) found that blood glucose, total protein, urea, Ca and P were not significantly affected by the addition of 15% WCS in the total diet of lactating cows. Homer et al. ( 1986) reported that plasma urea increased and glucose was not significantly affected by the addition 15% WCS in the total diet of lactating cows. Blood plasma triglycerides, cholesterol and phospholipids concentrations (Table 4) were significantly higher with the WCS diet and were due to high fat content. Barraza et al. ( 199 1) reported that the addition of WCS to the diet of lactating cows significantly increased the blood concentrations of cholesterol. Martinez et al. ( 199 1) found that the addition of 4% fat to the diet of cows increased plasma triglycerides, whereas glucose and urea were not affected by such treatment. Ferguson et al. ( 1990) reported that plasma concentrations of triglycerides and cholesterol were not affected by the addition of fat to the diet of lactating cows. In conclusion, the addition of WCS at 20% of the fresh weight of the concentrate of a diet containing maize silage, straw and concentrate, for lactating cows during hot weather, significantly increased milk yield (actual and 4% fat corrected), milk fat content and yield, and blood plasma triglycerides, cholesterol and phospholipids concentrations. Table 4 Blood plasma metabolite and electrolyte concentrations Item
Diets
SED
Level of significance
Control
WCS
Metabolites Glucose (mg (lOOml)-‘) Total protein (g (100 ml)-‘) Urea (mg (100 ml)-‘) Triglycerides ( mg ( 100 ml ) - ’) Cholesterol (mg (100 ml)-‘) Phospholipids (mg (100 ml)-‘)
60.4 9.1 14.7 15.9 173.2 169.6
62.1 8.5 19.3 18.8 225.1 225.6
4.34 0.63 6.12 1.29 11.33 10.15
NS NS NS * *** ***
Electrolytes (mg (100 rno-‘) Sodium Potassium Calcium Phosphorus Magnesium
331.9 19.0 9.8 5.8 2.3
339.4 18.9 10.2 6.0 2.3
1.77 0.69 0.46 0.48 0.08
NS
*Pi 0.05; -P-C 0.001; NS, not significant.
NS NS NS
NS
234 N.G. Belibasakis,D. Tsirgogianni/Animal Feed Science and Technology52 (1995) 227-235
Acknowledgements The authors would like to thank the Laboratory of Dairy Technology, Faculty of Agriculture, University of Thessaloniki, and P. Ambatzidis, for the milk analyses, and A. Nalpandoglou, for the sample feed analyses for NDF in this study.
References Association of Official Analytical Chemists, 1975. Official Methods of Analysis, 12th edn. AOAC, Washington, DC. Barraza, M.L., Coppock, C.E., Brooks, K.N., Wilks, D.L., Saunders, R.G. and Latimer, Jr., G.W., 199 1. Iron sulfate and feed pelleting to detoxify free gossypol in cottonseed diets for dairy cattle. J. Dairy Sci., 74: 3457-3467. Beede, D.K. and Collier, R.J., 1986. Potential nutritional strategies for intensively managed cattle during thermal stress. J. Anim. Sci., 62: 543-554. Berman, A., Folman, Y., Kaim, M., Mamen, M., Hen, Z., Wolfenson, D. and Arieli, A., 1985. Upper critical temperatures and forced ventilation effects for high-yielding dairy cows in a subtropical climate. J. Dairy Sci., 68: 1488-1495. Cochran, W.G. and Cox, G.M., 1957. Experimental Designs, 2nd edn. Wiley, New York, pp. 127133. Collier, R.J., Beede, D.K., Thatcher, W.W., Israel, L.A. and Wilcox, C.J., 1982. Influences of environment and its modification on dairy animal health and production. J. Dairy Sci., 65: 22 13-2227. Coppock, C.E., West, J.W., Moya, J.R., Nave, D.H., LaBore, J.M., Thompson, K.G., Rowe, Jr., L.D. and Gates, C.E., 1985. Effects of amount of whole cottonseed on intake, digestibility, and physiological responses of dairy cows. J. Dairy Sci., 68: 2248-2258. DePeters, E.J., Taylor, S.J., Franke, A.A. and Aguirre, A., 1985. Effects of feeding whole cottonseed on composition of milk. J. Dairy Sci., 68: 897-902. Ferguson, J.D., Sklan, D., Chalupa, W.V. and Kronfeld, D.S., 1990. Effects of hard fats on in vitro and in vivo rumen fermentation, milk production, and reproduction in dairy cows. J. Dairy Sci., 73: 2864-2879. Holter, J.B., Hayes, H.H., Urban, Jr., W.E. and Duthie, A.H., 1992. Energy balance and lactation response in Holstein cows supplemented with cottonseed with or without calcium soap. J. Dairy Sci., 75: 1480-1494. Homer, J.L., Coppock, C.E., Schelling, G.T., Labore, J.M. and Nave, D.H., 1986. Influence of niacin and whole cottonseed on intake, milk yield and composition, and systemic responses of dairy cows. J. Dairy Sci., 69: 3087-3093. Kajikawa, H., Odai, M., Saitoh, M. and Abe, A., 1991. Effects of whole cottonseed on ruminal properties and lactation performance of cows with different rumen fermentation patterns. Anim. Feed Sci. Technol., 34: 203-2 12. Knapp, D.M. and Grummer, R.R., 199 1. Response of lactating dairy cows to fat supplementation during heat stress. J. Dairy Sci., 74: 2573-2579. Lowman, B.C., Scott, A.N. and Somerrill, S.H., 1976. Condition scoring of cattle. East of Scotland College of Agriculture, Edinburgh, Bull. 6. Martinez, N., DePeters, E.J. and Bath, D.L., 199 1. Supplemental niacin and fat effects on milk composition of lactating Holstein cows. J. Dairy Sci., 74: 202-2 10. McDowell, R.E., 1972. Improvement ofLivestock Production in Warm Climates. W.H. Freeman, San Francisco, CA, 102 pp. National Research Council, 1988. Nutrient Requirements of Dairy Cattle, 6th edn. National Academy of Science Press, Washington, DC, pp. 1-157. Ryan, B.F., Joiner, B.L. and Ryan, T.A., 1985. Minitab: Handbook, 2nd edn. Duxbury Press, Boston, MA.
N.G. Belibasakis. D. Tsirgogianni /Animal Feed Science and Technology 52 (1995) 227-235 235 Skaar, T.C., Grummer, R.R., Dentine, M.R. and Stauffacher, R.H., 1989. Seasonal effects of preparturn and postpartum fat and niacin feeding on lactation performance and lipid metabolism. J. Dairy Sci., 72: 2028-2038. Smith, N.E., Collar, L.S., Bath, D.L., Dunkley, W.L. and Franke, A.A., 198 1. Digestibility and effects of whole cottonseed fed to lactating cows. J. Dairy Sci., 64: 2209-22 15. Smith, W.A., Harris, Jr., B., van Horn, H.H. and Wilcox, C.J., 1993. Effects of forage type on production of dairy cows supplemented with whole cottonseed, tallow, and yeast. J. Dairy Sci., 76: 2055 215. Van Soest, P.J. and Robertson, J.B., 1980. Systems of analysis for evaluating fibrous feeds. In: W.J. Pigden, C.C. Balch and M. Graham (Editors), Standardization of Analytical Methodology for Feeds. Publ. IDRC-134e, Int. Dev. Res. Center, Ottawa, Ont., pp. 49-60. Wilks, D.L., Coppock, C.E., Brooks, K.N. and Gates, C.E., 199 1. Effects of differences in starch content of diets with whole cottonseed or rice bran on milk casein. J. Dairy Sci., 74: 13 14-1320.
Animal Feed Science and Technology 52 ( 1995) 227-235
Effects of whole cottonseeds on milk yield, milk composition, and blood components of dairy cows in hot weather N.G. Belibasakis”,*, D. Tsirgogiannib “Department ofAnimal Husbandry, Faculty of Veterinary Medicine, Aristotelian University of Thessaloniki, Thessaloniki, Greece bGeneral Hospital ‘Agios Pavlos’of Thessaloniki, Thessaloniki, Greece Received 8 April 1994; accepted 7 September 1994
Abstract Sixteen multiparous Friesian cows, 70- 140 days post partum, were allotted to two groups of eight cows, according to calving date, lactation number and daily yield, and assigned randomly to one of two diets in a crossover design experiment. The two experimental diets were concentrate, containing either 20% whole cottonseeds and 13% soya bean meal or 14% cottonseed meal and 18.5% soya bean meal, plus a mixture of maize silage and straw in the proportions 8: 1 (fresh weight) ad libitum. The concentrate was offered individually, in two equal meals daily at 0.4 kg kg - I of milk produced, and the mixture of maize silage and straw was offered ad libitum once daily on a group basis. The experimental period lasted from 10 June to 4 August 1993, and the cows were housed in an open lot. Dry matter intake, milk protein content and yield, as well as content of milk lactose, total solids and solids not fat were not significantly affected by the diet. In contrast, whole cottonseeds supplementation increased actual milk yield (25.1 vs. 23.1 kg day-‘; PC 0.05), 4% fat-corrected milk yield (25.0 vs. 21.5 kg day-‘; PC 0.05), milk fat content (3.98 vs. 3.56%; P~0.05) and milk fat yield (1.0 vs. 0.82 kgday-‘; P~0.05). No significant differences were observed in blood plasma concentrations of glucose, total protein, urea, sodium, potassium, calcium, phosphorus and magnesium. In contrast, increased concentrations in plasma of triglycerides ( 18.8 vs. 15.9 mg ( 100 ml)-‘; P-c 0.05), cholesterol (225.1 vs. 173.2 mg (100 ml)-‘; P
* Corresponding
Lactation performance
author.
0377-8401/95/$09.50 0 1995 Elsevier Science B.V. All rights reserved SSDI 0377-8401(94)00725-X
228 N.G. Belibasakis, D. Tsirgogianni /Animal Feed Science and Technology 52 (1995) 227-235
1. Introduction In summer, as temperature rises above the upper critical temperature of 25°C for Holstein Friesian cows (Berman et al., 1985 ), high-producing dairy cows often fail to consume sufficient feed (Collier et al., 1982), particularly of roughage rather than concentrate (McDowell, 1972)) to meet their nutrient requirements, especially energy. Formulating diets with supplemental fat has been advocated as a possible means of reducing heat stress on lactating cows, owing to their high energy content and low heat increment of fat relative to other nutrients (Beede and Collier, 1986). Skaar et al. ( 1989) found that cows calving during warm season months (2 April- 1 August) and consuming diets supplemented with 5% fat produced more milk than herdmates not receiving fat, but milk composition was not affected by treatment. Knapp and Grummer ( 199 1) reported that adding 5% fat to diets for cows during hot weather increased milk fat content, but milk yield and milk protein content and yield were not affected. The addition of whole cottonseeds (WCS) to diets for lactating cows during hot weather could be beneficial for milk production. This is because WCS is a rich source of fat, protein and fibre to improve the energy, protein and libre balance of dairy cows. Fat in WCS is encapsulated by a seed coat that may limit the nutritional problems for cows given large amounts of fat. Also, Holter et al. ( 1992) reported that addition of 15% WCS to diets for lactating cows reduced total heat production by 6% and reduced heat in excess of maintenance by 8%. The objectives of this experiment were to evaluate effects of WCS in a concentrate diet containing either 20% WCS and 13% soya bean meal or 14% cottonseed meal and 18.5% soya bean meal, plus a mixture of maize silage and straw, on milk yield, milk composition, dry matter intake, body condition score, and blood plasma metabolites and electrolytes of lactating cows during hot weather.
2. Materials and methods 2.1. Experimental animalsand diets Sixteen multiparous Friesian cows, 70-140 days post pat-turn, weighing approximately 600 kg at the beginning of experiment, were allotted according to calving.date, lactation number and daily milk yield into two groups of eight cows each, and assigned randomly to one of two diets in a crossover design experiment (Cochran and Cox, 1957 ). The two experimental diets were concentrate containing 0% or 20% WCS (fresh weight ) plus a mixture of maize silage and straw in the proportions 8: 1 (fresh weight) ad libitum. Chemical composition of concentrate mixtures, maize silage and straw, and the ingredients of concentrate mixtures, are shown in Table 1. The cows remained on trial for 11 weeks, from 20 May to 4 August 1993. The first 3 weeks were the
N.G. Belibasakis, D. Tsirgogianni /Animal Feed Science and Technology 52 (1995) 227-235 229 Table 1 Chemical composition trate mixtures (O/o) Parameter
Chemical analysis2 Dry matter Crude protein Ether extract Crude fibre Neutral detergent fibre ME3 (MJ kg-‘) Ingredients 4 Ground maize Barley Soya bean meal Maize gluten meal Cottonseed meal Whole cottonseeds Dicalcium phosphate Calcium carbonate’ Magnesium oxide5 Mineral-vitamin mix Salt Total
of concentrate
mixtures, maize silage and straw, and ingredients
Concentrate Control
WCS’
81.4 24.3 3.2 6.3 14.9 13.0
87.5 24.3 6.3 6.2 14.3 13.3
39.5 12.3 18.5 11.3 14.0
37.0 12.0 13.0 12.5
0.4 2.0 1.0 1.0 100.0
of concen-
Maize silage
Straw
30.2 8.3 3.1 26.8 50.7 9.6
90. I 4.5 1.5 42.4 75.2 7.1
20.0 1.0 2.3 0.2 1.0 1.0 100.0
‘WCS-Whole cottonseeds. ‘Dry matter basis except dry matter. 3Metabolizable energy calculated according to the National Research Council ( 1988). Energy values are expressed in megajoules on the assumption that 1 Meal is equivalent to 4. I84 MJ. “Fresh weight basis. ‘Amounts of Ca and Mg in WCS diet were adjusted above those in the control diet, because added fat increases Ca and Mg soap formation in the rumen and the excretion of these elements in the faeces (National Research Council, 1988).
adjustment period, and the following 8 weeks included two experimental periods of 4 weeks each. During the adjustment period, all cows were given the concentrate mixture without WCS (control diet) plus the mixture of maize silage and straw. During the first experimental period ( 10 June-7 July) one group of cows was fed on the control diet and the other group on the diet with WCS. During the second experimental period (8 July-4 August) the cows were changed to the other diet. The concentrate was offered individually, in tie-stalls, in two equal meals daily at 0.4 kg kg-’ milk produced. Concentrate refusals were removed when the cows left the tie-stalls. Concentrate allowances were adjusted weekly on the previous week’s milk production. The mixture of maize silage and straw was offered ad libitum
230 N.G. Belibasakis, D. Tsirgogianni /Animal FeedScience and Technology 52 (1995) 227-235
once daily on a group basis. Silage and straw refusals were removed daily and weighed. The two groups of cows were housed in an open lot. Twice daily, at 06:OOand 17:OOh, the cows were brought into the tie-stalls for milking and feeding. Water was available to the cows at all times in the open lot area. Body condition score of cows was measured on a system with l-5 scale on the first and last day of each experimental period (Lowman et al., 1976). 2.2. Sample collection and analyses Milk yield was recorded for all animals at each milking during the last 2 weeks of each experimental period. Milk samples were taken at each milking during the last 3 days of each period and analysed for total solids (TS ) , fat, solids-not-fat (SNF), crude protein (CP ), and lactose using a milk analyser (Milco Scan 104 A/s, N. Foss Electric, Hillerod). Samples of maize silage and straw were taken weekly and samples of concentrate mixtures were taken while mixing. The samples of feed were analysed for dry matter (DM ), CP, crude fibre (CF), and ether extract (EE) according to the Association of Official Analytical Chemists (1975), and for neutral detergent fibre (NDF) as described by Van Soest and Robertson ( 1980). Blood samples were drawn from the tail vein into heparinized tubes on the last day of each experimental period, at about 4 h after feeding, and centrifuged. Plasma was stored at -20°C until analysed for glucose, total protein, urea, triglycerides, cholesterol, phospholipids, Na, K, Ca, P and M, using a DuPont Dimension automated clinical chemistry analyser validated for bovine samples (DuPont Dimension 380, Wilmington, DE). 2.3. Statistical analysis Milk yield, milk composition, dry matter intake (DMI) of concentrates, body condition score and blood plasma components data were tested by analysis of variance with two factors using the Minitab Statistical Package (Ryan et al., 1985 ) . The model contained effects of cow, period and diet. Effects were considered significantly different at P-C0.05.
3. Results and discussion In the Cotton and Industrial Plants Institute (CIPI), which is about 2.5 km from the experimental dairy farm, the average maximum temperature during the experimental periods was 32.7’ C (SE 0.36’ C ). The weekly air temperature and relative humidity during the experimental periods according to CIPI records are shown in Table 2.
N.G. Belibasakis, D. Tsirgogianni /Animal Feed Science and Technology 52 (1995) 227-235 23 1 Table 2 Average weekly air temperature August 1993)’ Date
IO-16 June 17-23 June 24-30 June 1-7 July 8-14 July 15-2 1 July 22-28 July 29 July-4 August
and relative humidity during the experimental
Temperature
( “C)
periods ( 10 June-4
Relative humidity (%)
Maximum
Minimum
OS:00 h
14:OOh
31.9 30.4 31.0 34.0 33.0 32.4 32.4 34.4
26.2 20.6 22.6 25.0 20.6 23.6 22.2 25.4
72.0 56.0 52.0 54.2 51.4 59.0 57.6 54.6
51.0 41.0 44.0 36.0 36.0 48.0 34.0 39.0
‘Records of the Cotton and Industrial Plants Institute, Sindos Thessaloniki, Greece.
3.1. Feed intake Mean daily DMI, metabolizable energy intake and crude protein intake (Table 3 ) were unaffected by treatment during hot weather. Daily feed DMI was not affected by the addition of WCS from 0% to 20% of the diets for lactating cows (Coppock et al. 1985; DePeters et al., 1985; Homer et al., 1986). However, when WCS increased to 30% of the diets the DMI decreased significantly (Coppock et al., 1985). 3.2. Milk yield and composition Mean daily milk yield and 4% fat-corrected milk (Table 3 ) were 2 kg day- ’ and 3.5 kg day-’ higher, respectively, with the WCS diet; the differences were significant (P< 0.05 ). Also, milk fat content and yield (Table 3) were higher by 0.42 percentage units and 180 g day-’ (P
232 N.G. Belibasakis, D. Tsirgogianni /Animal Feed Science and Technology 52 (1995) 227-235 Table 3 Average dry matter intake, milk production and composition
on the two diets
Diets
Dry matter intake (kg day-‘) Total Concentrate Maize silage-straw mixture Metabolizable energy intake (MJ day-’ ) Crude protein intake (kg day-’ ) Milk production (kg day-’ ) Actual milk yield 4% FCM’ yield Fat yield Protein yield Milk composition (%) Total solids Fat SNF’ Protein Lactose Body condition score
Control
WCS’
17.3 7.9 9.4 186.5 2.6
17.4 8.1 9.3 190.6 2.6
SED
Level of significance
0.42
NS
23.1 21.5 0.82 0.71
25.1 25.0 1.0 0.76
0.97 1.27 0.07 0.04
* * * NS
11.74 3.56 8.18 3.06 4.41 2.98
12.11 3.98 8.13 3.04 4.39 3.11
0.28 0.17 0.13 0.10 0.09 0.07
NS * NS NS NS NS
‘WCS-Whole cottonseeds. 2FCM-Fat-corrected milk. 3SNF-Solids not fat. *P-C 0.05; NS, not significant.
straw significantly increased actual milk yield, 4% fat-corrected milk yield, and milk fat content and yield of the cows during hot weather. Milk protein content and yield (Table 3 ) were not significantly affected by the addition of WCS to the diet. Similar results have been reported by Skaar et al. ( 1989), and Knapp and Grummer ( 1991) when 5% fat was added to diets of lactating cows during hot weather. Also, Ferguson et al. ( 1990) and Holter et al. ( 1992) found no change in milk protein content by the addition of 3-9% fat and 15% WCS, respectively, to diets of lactating cows. However, other studies showed a decrease of milk protein content with the addition of WCS to diets for lactating cows (Smith et al., 1981; DePeters et al., 1985; Horner et al., 1986; Wilks et al., 199 1; Smith et al., 1993). Milk lactose, TS and SNF content (Table 3 ) were not significantly affected by the WCS diet. 3.3. Body condition score Body condition score (Table 3) was not significantly affected by the addition of WCS to diets for dairy cows during hot weather.
N.G. Belibasakis, D. Tsirgogianni /Animal Feed Science and Technology 52 (1995) 227-235 233
3.4. Blood plasma components
Blood plasma glucose, total protein, urea, Na, K, Ca, P and Mg concentrations (Table 4) were not significantly affected by the addition of WCS to the diet of cows. Coppock et al. ( 1985 ) found that blood glucose, total protein, urea, Ca and P were not significantly affected by the addition of 15% WCS in the total diet of lactating cows. Homer et al. ( 1986) reported that plasma urea increased and glucose was not significantly affected by the addition 15% WCS in the total diet of lactating cows. Blood plasma triglycerides, cholesterol and phospholipids concentrations (Table 4) were significantly higher with the WCS diet and were due to high fat content. Barraza et al. ( 199 1) reported that the addition of WCS to the diet of lactating cows significantly increased the blood concentrations of cholesterol. Martinez et al. ( 199 1) found that the addition of 4% fat to the diet of cows increased plasma triglycerides, whereas glucose and urea were not affected by such treatment. Ferguson et al. ( 1990) reported that plasma concentrations of triglycerides and cholesterol were not affected by the addition of fat to the diet of lactating cows. In conclusion, the addition of WCS at 20% of the fresh weight of the concentrate of a diet containing maize silage, straw and concentrate, for lactating cows during hot weather, significantly increased milk yield (actual and 4% fat corrected), milk fat content and yield, and blood plasma triglycerides, cholesterol and phospholipids concentrations. Table 4 Blood plasma metabolite and electrolyte concentrations Item
Diets
SED
Level of significance
Control
WCS
Metabolites Glucose (mg (lOOml)-‘) Total protein (g (100 ml)-‘) Urea (mg (100 ml)-‘) Triglycerides ( mg ( 100 ml ) - ’) Cholesterol (mg (100 ml)-‘) Phospholipids (mg (100 ml)-‘)
60.4 9.1 14.7 15.9 173.2 169.6
62.1 8.5 19.3 18.8 225.1 225.6
4.34 0.63 6.12 1.29 11.33 10.15
NS NS NS * *** ***
Electrolytes (mg (100 rno-‘) Sodium Potassium Calcium Phosphorus Magnesium
331.9 19.0 9.8 5.8 2.3
339.4 18.9 10.2 6.0 2.3
1.77 0.69 0.46 0.48 0.08
NS
*Pi 0.05; -P-C 0.001; NS, not significant.
NS NS NS
NS
234 N.G. Belibasakis,D. Tsirgogianni/Animal Feed Science and Technology52 (1995) 227-235
Acknowledgements The authors would like to thank the Laboratory of Dairy Technology, Faculty of Agriculture, University of Thessaloniki, and P. Ambatzidis, for the milk analyses, and A. Nalpandoglou, for the sample feed analyses for NDF in this study.
References Association of Official Analytical Chemists, 1975. Official Methods of Analysis, 12th edn. AOAC, Washington, DC. Barraza, M.L., Coppock, C.E., Brooks, K.N., Wilks, D.L., Saunders, R.G. and Latimer, Jr., G.W., 199 1. Iron sulfate and feed pelleting to detoxify free gossypol in cottonseed diets for dairy cattle. J. Dairy Sci., 74: 3457-3467. Beede, D.K. and Collier, R.J., 1986. Potential nutritional strategies for intensively managed cattle during thermal stress. J. Anim. Sci., 62: 543-554. Berman, A., Folman, Y., Kaim, M., Mamen, M., Hen, Z., Wolfenson, D. and Arieli, A., 1985. Upper critical temperatures and forced ventilation effects for high-yielding dairy cows in a subtropical climate. J. Dairy Sci., 68: 1488-1495. Cochran, W.G. and Cox, G.M., 1957. Experimental Designs, 2nd edn. Wiley, New York, pp. 127133. Collier, R.J., Beede, D.K., Thatcher, W.W., Israel, L.A. and Wilcox, C.J., 1982. Influences of environment and its modification on dairy animal health and production. J. Dairy Sci., 65: 22 13-2227. Coppock, C.E., West, J.W., Moya, J.R., Nave, D.H., LaBore, J.M., Thompson, K.G., Rowe, Jr., L.D. and Gates, C.E., 1985. Effects of amount of whole cottonseed on intake, digestibility, and physiological responses of dairy cows. J. Dairy Sci., 68: 2248-2258. DePeters, E.J., Taylor, S.J., Franke, A.A. and Aguirre, A., 1985. Effects of feeding whole cottonseed on composition of milk. J. Dairy Sci., 68: 897-902. Ferguson, J.D., Sklan, D., Chalupa, W.V. and Kronfeld, D.S., 1990. Effects of hard fats on in vitro and in vivo rumen fermentation, milk production, and reproduction in dairy cows. J. Dairy Sci., 73: 2864-2879. Holter, J.B., Hayes, H.H., Urban, Jr., W.E. and Duthie, A.H., 1992. Energy balance and lactation response in Holstein cows supplemented with cottonseed with or without calcium soap. J. Dairy Sci., 75: 1480-1494. Homer, J.L., Coppock, C.E., Schelling, G.T., Labore, J.M. and Nave, D.H., 1986. Influence of niacin and whole cottonseed on intake, milk yield and composition, and systemic responses of dairy cows. J. Dairy Sci., 69: 3087-3093. Kajikawa, H., Odai, M., Saitoh, M. and Abe, A., 1991. Effects of whole cottonseed on ruminal properties and lactation performance of cows with different rumen fermentation patterns. Anim. Feed Sci. Technol., 34: 203-2 12. Knapp, D.M. and Grummer, R.R., 199 1. Response of lactating dairy cows to fat supplementation during heat stress. J. Dairy Sci., 74: 2573-2579. Lowman, B.C., Scott, A.N. and Somerrill, S.H., 1976. Condition scoring of cattle. East of Scotland College of Agriculture, Edinburgh, Bull. 6. Martinez, N., DePeters, E.J. and Bath, D.L., 199 1. Supplemental niacin and fat effects on milk composition of lactating Holstein cows. J. Dairy Sci., 74: 202-2 10. McDowell, R.E., 1972. Improvement ofLivestock Production in Warm Climates. W.H. Freeman, San Francisco, CA, 102 pp. National Research Council, 1988. Nutrient Requirements of Dairy Cattle, 6th edn. National Academy of Science Press, Washington, DC, pp. 1-157. Ryan, B.F., Joiner, B.L. and Ryan, T.A., 1985. Minitab: Handbook, 2nd edn. Duxbury Press, Boston, MA.
N.G. Belibasakis. D. Tsirgogianni /Animal Feed Science and Technology 52 (1995) 227-235 235 Skaar, T.C., Grummer, R.R., Dentine, M.R. and Stauffacher, R.H., 1989. Seasonal effects of preparturn and postpartum fat and niacin feeding on lactation performance and lipid metabolism. J. Dairy Sci., 72: 2028-2038. Smith, N.E., Collar, L.S., Bath, D.L., Dunkley, W.L. and Franke, A.A., 198 1. Digestibility and effects of whole cottonseed fed to lactating cows. J. Dairy Sci., 64: 2209-22 15. Smith, W.A., Harris, Jr., B., van Horn, H.H. and Wilcox, C.J., 1993. Effects of forage type on production of dairy cows supplemented with whole cottonseed, tallow, and yeast. J. Dairy Sci., 76: 2055 215. Van Soest, P.J. and Robertson, J.B., 1980. Systems of analysis for evaluating fibrous feeds. In: W.J. Pigden, C.C. Balch and M. Graham (Editors), Standardization of Analytical Methodology for Feeds. Publ. IDRC-134e, Int. Dev. Res. Center, Ottawa, Ont., pp. 49-60. Wilks, D.L., Coppock, C.E., Brooks, K.N. and Gates, C.E., 199 1. Effects of differences in starch content of diets with whole cottonseed or rice bran on milk casein. J. Dairy Sci., 74: 13 14-1320.