EFFECT OF DIETARY FAT SUPPLEMENTATION ON THE REPRODUCTION RESPONSE TO PROSTAGLANDIN ( PGF2Α) INJECTION IN POST PARTUM BUFFALO-COWS.

EFFECT OF DIETARY FAT SUPPLEMENTATION ON THE REPRODUCTION RESPONSE TO PROSTAGLANDIN ( PGF₂Α) INJECTION IN POST PARTUM BUFFALO-COWS.

UMIMA M.M. and R.H. OSMAN

Animal Reproduction Research Institute, Cairo, Egypt.

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                                                   ABSTRACT

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Key Words: Dietary fat, PGF₂A, buffalo-cows.

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INTRODUCTION

Estrus synchronization decreased the inter calving period and allowed artificial insemination planning according to a time and scheme, also allows to stagger the plan parturitions beginning in a specific period of time (Martineau, 2003).

The hormone  PGF₂α is important for uterine involution and ovarian function, that is able to synchronize estrus by inducing regression of the corpus luteum (Xiang – Dong, 2003).

However, the possibility of modifying the estrus cycle through hormonal treatment still has some obstacles. Fatty acid levels and antioxidants are factors affecting calving interval and first service of artificial insemination in cattle and buffaloes.

Nutritional approaches have been used to improve reproductive performance in cattle. Plasma lipid profiles, hormone concentration and follicular dynamics can be attended by including fat in live stock diets (Lucy et al., 1991). Some polyunsaturated long chain fatty acids can serve as substrates for biosynthesis of the prostaglandins for mammals (Mattos et al., 2000). Arachidonic acid is the main substrate for prostaglandins (Attar et al., 2009 and Cammas et al., 2006). Increasing dietary energy density by feeding supplemental fat  may  enhance metabolic efficiency. Theoretically, if feeding supplemental fat increases energy intake, severity of negative energy balance may be reduced and better health and improved reproductive efficiency may result (Curtis et al., 1985).                                                               

Also the other main factor affecting reproduction is antioxidants. They are also key signal molecules modulating various reproductive functions and can be affected by type of supplemented fat (Vazquez   et al., 2008). Free radicals can influence the oocyte, sperm, and embryo in their micro environment (for example follicular fluid, hydrosalpingeal fluid, and peritoneal fluid). These microenvironments have a direct bearing on the quality of oocytes, sperm oocyte interaction, implantation and early embryo development. Oxidative stress affects both implementation and early embryo  development (Ashok et al., 2006).                                                                                                     

Thus our objective was to determine whether increasing the level of fat percent of the dry matter of the diet by dietary fat supplement to post partum dairy buffaloes would improve the reproductive response after synchronization using PGF_2α.                                                               

MATERIALS and METHODS

Experimental animals:-                                                 

For this study 40 multiparous lactating buffalo-cows (aged 6 to 8 years) after parturition were selected and has a history of persistent C.L. Buffaloes were divided into two groups according to their fat percent of the diet, the first group left without treatment (control group) n=16 were fed the basal diet TMR. The second group (n=24) was given the basal diet plus cotton seed oil 2% fat of the dry matter. Cotton seed oil was offered from parturition till the end of experiment (60 days post insemination).                                                                              

Feeding regime:-

TMR Mixture was offered as 15-17 kg dry matter per animal. It's chemical analysis was crude protein 16% and ether extract 2%. The basal diet offered to all animals and covered their requirement. TMR containing fat was prepared by adding cotton seed oil (2% of the dry matter plus the basal diet). All buffaloes showed mature C.L. were injected with 500 μg single dose of PGF₂α analogue (Estrumate, Schering-Plough Animal Health). The buffaloes (control and treated) that showed estrus were artificially inseminated 72 hours post injection (timed A.I). The inseminated animal were examined rectaly to asses pregnancy after 60 days post insemination (conception rate).

Sampling, measurements and analysis:

Blood samples were collected from all animals just before injection of PGF₂α (60 days PP.) and one month after injections (90 days PP). Serum glucose, triglyceride and cholesterol were analysed using kits Fatty acids were extracted from serum with methanol: chloroform (2:1 vol/vol) Loor et al. (2004), methylated and then subjected to gas chromatography. Total antioxidants were determined using specific kits. Serum zinc and copper levels were determined by using atomic absorption spectrophotometer.

Statical analysis:

The obtained data were statically analysed by student T test according to the method described by (Snedecor and Cochran, 1987).               

RESULTS

Serum glucose, triglyceride and cholesterol analysis:

Our results revealed that serum glucose concentration was not significantly affected by fat supplementation .While triglycerides were significantly increased with cotton seed oil supplementation compared with control group at 90 days PP, and cholesterol at both 60 &90 days PP (table 1).

Fatty acid analysis:

Our results revealed that serum concentration of palmitic, stearic. oleic, linoleic and linolenic fatty acids were significantly increased with cotton seed oil supplementation group (table 2), and was more markedly increased when it was added to diet for 3months.                 

Serum copper, zinc and total antioxidants analysis:

Results illustrated non significant effect on serum concentration of copper and zinc by fat supplementation compared to control Where total antioxidants was significantly increased in the supplemented group at 90 days PP (table 3).

Conception rate:

On the other hand (table 4) declared that the overall mean of total conception rates (first and second insemination) in buffaloes supplemented with cotton seed oil were significantly increased (83.3%) than non supplemented ones (68.75%).

Table 1: Serum glucose, triglyceride and cholesterol in buffaloes supplemented with 2% cotton seed oil compared with control group (mean ± SE).

* Data with different subscript (a,b at 60 days and A,B at 90 days PP) in the same row are significantly differ at (P<0.05).

 Table 2: Serum fatty acid analysis in buffaloes supplemented with 2% cotton seed oil compared with control group (mean ± SE).

* Data with different subscript (a,b at 60 days and A,B at 90 days PP) in the same row are significantly differ at (P<0.05).

Table 3: Serum copper, Zinc and total antioxidant in buffaloes supplemented with 2% cotton seed oil compared with control group (mean ± SE)

* Data with different subscript (a,b at 60 days and A,B at 90 days PP) in the same row are significantly differ at (P<0.05).

Table 4: Total conception rates in control and supplemented groups.

  * Data with different subscript (a, b) in the same row are significantly differ at P<0.05).

DISCUSSION

In the present study there was significant increase in serum triglycerides and cholesterol concentration in buffaloes fed cotton oil diets compared with control. This result was consistent with previous result (Grummer and Carroll, 1991) as dietary fat supplementation in cows consistently increases plasma concentrations of cholesterol. Fats which include cholesterol, triglycerol and phospholipids are major component of cellular membranes and are a source of fatty acids for the synthesis of a variety of effectors molecules such as prostaglandins. Cholesterol is another component of the cellular membrane and is the precursor for the synthesis of steroids hormones. Increased concentration of plasma progesterone in luteal phase before and after insemination have been associated with higher pregnancy rate (Buttler et al., 1996).

Fats in the diet can influence reproduction positively by altering both ovarian follicle and corpus luteum function via improved energy status and increasing precursors for the synthesis of reproductive hormones such as steroids and prostaglandins (Staples et al., 1998).                                      

Feeding cotton oil for 3 months increased significantly palmitic, oleic, linoleic and linolenic fatty acids. These observation agreed with previous studies reported by Abughazaleh et al. (2003) and  Loor et al. (2005) who supplemented fat to cows.                                             

Prostaglandin F2a (PGF)appears to be the normal physiological signal whereby the uterus causes regression of the CL at the end of the estrous cycle. During the early postpartum period, high PGF concentrations probably prolong the interval to normal CL function because hysterectomy reduces PGF concentrations and maintains normal CL function (Edqvist et al., 1982; Lindell et al., 1982a,b; Madej et al., 1984 and Copelin et al., 1987).

The significant higher concentration of serum palmitic and oleic acid as saturated fatty acids in the supplemented group compared to control group is due to hydrogenation of the unsaturated fatty acids found in cotton oil to a saturated form in the rumen or absorbed from the diet. The chemical composition of cotton seed oil and it’s fatty acid profile generally consists of 18% mono saturated (oleic) and 26%saturated palmitic and stearic and 52% poly unsaturated linoliec acid.The bovine CL contains enormous quantities of arachidonic acid (Lukaszewska and Hansel, 1980) and has the biosynthetic capacity to metabolize this into a variety of products. It is the purpose to focus on two of these metabolites, PGI2 and 5-HETE (5-Hydroxyeicosatetraenoic acid), and to ascribe roles for them in the regulation of the bovine CL. Post partum anestrus commonly is referred to as postpartum interval (PPI), the interval from parturition to first estrus. Intervals to other endpoints such asto ovulation or to conception also are important, but from a practical point of view, estrus is the most logical measure of the commencement of potential fertility.

The significant higher serum linoliec and linolenic acid in the supplemented group compared to control indicated that some of the polyunsaturated fatty acids in the cotton oil escape the ruminal biohydrogenation and absorbed from the small intestine (Klusmeyer and Clark, 1991). Calculated the biohydrogenation of unsaturated C₁₈ fatty acids to be approximately 70% using ruminally and duodenally cannulated lactating dairy cows.

Nutritional effects are elicited via a complex interplay among many variables such as quantity and quality of feed intake, nutrient reserves stored in the body and competition for nutrients from other physiological functions besidesreproduction (Dunn and Kaltenbach, 1980; Short and Adams,1988 and Randel, 1990).

Previous research showed that greater proportion of cows fed long chain fatty acid showed stronger signs of estrus (71.4 vs 65.5%), exhibited standing estrus, had more active ovaries (75.4 vs 69.5% as determined by rectal palpation done every 2 to 4 week) and required less exogenous PGF_2α to induce estrous (43.7 vs 55.7%) (Staples et al., 1998).                                       

Greater concentration of lioniec and linolenic acids in the oil may depress PGF_2α to a greater extent, thus allowing greater synthesis and secretion of progesterone from granulosa and luteal cells (Filley  et al., 2000). Mattos et al. (2000) suggested that the improvement effects of dietary fat on fertility of dairy cows was probably not a result of improvement of the energy status of the cow but that increased fertility could be due to effects of dietary fatty acids on the pituitary, ovaries and uterus.                                                                                  

Our results showed no significant change in serum copper and zinc in the cotton oil supplemented group compared with the control. Where there were significant increase in the level of serum total antioxidant in the supplemented group. Our results showed that cotton seed oil supplementation has antioxidative effect in postpartum cows. The same results observed by Moises (2006).

Cotton seed oil is rich in tocopherols (Duffy and Roberta, 2002), theoretically tocopherols isolated from cotton seed oil by (Emerson et al., 1936). Vitamin E plays a role in preserving other vitamins (such as vitamin C and A) in body and protecting tissues against oxidation which might lead to inflammations and diseases Henmitt et al. (2003) revealed that antioxidant supplementation with vitamin E has been shown to have beneficial effects in preventing luteal phase deficiency and resultant increased pregnancy rate.

The significant higher conception rate observed in the dietary fat supplemented group compared to the control may be due to feeding dietary enrichment in linoleic and liolenic acid for postpartum cows which can influence fatty acids in plasma. The fatty acids in plasma can modulate the fatty acids in endometrial tissues and can modulate circulatory and intrauterine prostaglandins (E2 & F2). Prostaglandin E2 in uterine fluids has been previously reported to be associated with embryo survival and development (Chartrand    et al., 2003). Also (Lokesh et al., 1992) reported that only the long chain fatty acids from the dietary fat were incorporated into liver lipids. The arachidonic acid in liver lipids was enhanced after supplementation of diets with sunflower oil. However the reduction in prostaglandins may be useful in reducing inflammatory responses mediated via prostaglandins. In addition Parmjit et al. (1992) suggested that high level of dietary fatty acids alter muscle membrane composition also result in alteration in glucose transport and the metabolism of muscle protein.

Zcheng et al. (2001) revealed that dietary poly unsaturated fatty acids (PUFAs) intake can reduce the endometrial capacity to produce prostaglandins and may therefore have implications for the control of luteolysis and other prostaglandin mediated events such as ovulation. Therefore, the role played by PUFAs and eicosanoids in fertility show that feeding or infusing different types of fat with varying PUFA content to females can alter: the number and size of ovarian follicles, the ovulation rate, progesterone production by the corpus luteum and the timing of luteolysis.

Finally we can conclude that increasing level of fat percent by 2% cotton seed oil in the dry matter of the diet to post partum dairy buffaloes improve the reproductive response after synchronization using PGF_2α.

REFERENCES

Abu Ghazaleh, A.A.; Schingoeth, D.J.; Hippen, A.R. and Kalscheur, K.F. (2003): Conjugated linoleic acid and vaccenic acid in rumen, plasma and milk of cows fed fish oil and facts differing in saturation of 18 carbon fatty acids. J. Dairy Sci. 86: 36-48.

Ashok, A.; Sajal, G. and Suresh, S. (2006):The role of free radicals and antioxidants in reproduction. Curr. Opin. Obstet. Cynecol. 18: 325-332.

Attar, E.; Tokunaga, H.; Imir, G.; Yilmaz, M.B.; Redwine, D.; Putman and Gurates, M. (2009):Prostaglandin E2 via steroidogenic factor-1 coordinately regulates transcription of steroidogenic genes necessary for estrogen synthesis in endometriosis. J. Clinic. Endocr. and Metab., Vol.94, No.2, (February 2009), (623-631).

Butler, W.K.; Calaman, J.J. and Beam, S.W. (1996): Plasma and milk urea nitrogen in relation to pregnancy rate in lactating dairy cattle. J. Anim. Sc. 74: 858-865.

Cammas, L.; Reinaud, P.; Bordas, N.; Dubois, O.; Germain, G. and Charpigny, G. (2006): Developmental regulation of prostacyclin synthase and prostacyclin receptors in the ovine uterus and conceptus during the peri-implantation period. Reproduction May 1, 131: 917-927.

Chartrand, R.; Matte, J.J.; Lessard, M.; Chouinard, PY.; Giquere, A. and Laforest, JP. (2003):Effects of dietary fat sources on systemic and intrauterine synthesis of prostaglandins during early pregnancy in gilts. J. Anim. Sci, 81(3): 726-34.

Copelin, I.P.; Smith, M.F.; Garverickm, H.A. and Youngquistm, R.S. (1987): Effect of the uterus onsubnormal luteal function in anestrous beef cows. J. Anim.Sci. 64: 1506.

Curtis, C.R.; Erb, H.N.; Sniffen, C.J.; Smith, D.R. and Kronfeld, D.S. (1985):Path analysis of dry period nutrition, postpartum metabolic and reproductive disorders, and mastitis in Holstein cows. J. Dairy Sci.  68: 23-47.

Duffy, E. and Roberta, J. (2002): American Dietetic Association : Complete food and Nutrition Guide,2^nd ed. John Wiley and sons, Inc Hoboken, NI.

Dunn, T.G. and Kaltenbach, C.C. (1980): Nutrition and the postpartum interval of the ewe, sow and cow. J. Anim. Sci. Sl (Supp1. 2): 29.

Edqvist, L.E.; Kindahl, H. and Stabenfeldt, G. (1982): Release of prostaglandin F_2α during the bovine prepartal period. Prostaglandins 16: 1-11.

Emerson, O.H.; Emerson, G.A. and Evans, H.M. (1936): The isolation from cotton seed oil of an alcohol resembling alphatochopherols from wheat germ oil. Science 1; 83 (2157): 421.

Filley, S.J.; Turner, H.A. and Stormshak, F. (2000): Plasma fatty acids prostaglandin F2α metabolite and reproductive response in postpartum heifers fed rumen bypass fat. J. Anim. Sci. 78: 139-144.

Grummer, R.R. and Carroll, D.J. (1991): Effects of dietary fat on metabolic disorders and reproductive performance of dairy cattle. J. Anim. Sci. 69: 3838–3852.

Henmitt, A.; Endot, J. and Kitajimay, R. (2003):Effectsof ascorbic acid supplementation on serum progesterone levels in patients with a luteal phase defect. Fertil steril, 80: 459-461.

Klusmeyer, T.H. and Clark, J.H. (1991): Effects of dietary fat and protein on fatty acid flow to the duodenum and in milk produced by dairy cows. J. Dairy Sci. 74: 30-55.

Lindell, J.O.; Kindahl, H.; Edqvist, L.E. and Tufvesson, G. (1982)a: Effect of hysterectomy on the postpartum prostaglandin levels in thecow. Acta Vet. Scand. 23: 144-150.

Lindell, J.O.; Kindahl, H.; Jansson, L. and Edqvist, L.E. (1982)b: Post-partum release of prostaglandin F2a and uterine involution in thecow. Theriogenology 17: 237.

Lokesh, B.; Licari, J. and Kinsella, J.E. (1992): Effect of different triglycerides on liver fatty acids and prostaglandin synthesis by mouse peritoneal cells. JPEN J parenter Enteral Nut, 16(4): 316-21.

Loor, J.J.; Ferlay, A.; Ollier, A.; Doreau, M. and Chilliard, Y. (2005):Relationship among trans and conjugated fatty acids and bovine milk fat yield due to dietary concentrate and linseed oil. J. Dairy Sci. 88: 726-740.

Loor, J.J.; Ueda, K.; Ferlay, A.; Chittiard, R. and Doreau, M. (2004): Biohydrogeneration, duodenal flora and intestinal digestion of trans fatty acids and conjugated linoleic acids in response to dietary forage: concentrate ratio and linseed oil in dairy cows. J. Dairy Sci. 87: 2477-2485.

Lucy, M.C.; Staples, C.R.; Michel, F.M. and Thater, W.W. (1991): Energy balance and size number of ovarian follicles detected by ultrasonography in early postpartum dairy cows. J. Dairy Sci. 4: 473-482.

Lukaszewska, J. and Hansel, W. (1980): Corpus luteum maintenance during early pregnancy in the cow. J. Reprod. Fertil. 59: 485-495.

Madej, A.; Kindahl, H.; Woyno, W.; Edqvist, L.E. and Stupnicki, R. (1984): Blood levels of 15-keto-13, 14 dihydro-prostaglandin F_2α during the postpartum periodin primiparous cows. Theriogenology 21: 279-289.

Martineau, R. (2003):Dinopros versus clorprostenol: Does route of injection modulate their efficacy in dairy cattle. The Bovine Practitioner 37(1): 10-19.

Mattos, R.; Charles, R.S. and William, W.T. (2000): Effects of dietary fatty acids on reproduction in ruminants. J. Rep. Fert. 5: 38-45.

Moises, C.F. (2006): Strategies to enhance fertility in dairy cattle during summer including use of cryopreservation of in vitro produced embryo. A thesis presented for the degree of Master of Science. Univ. of Florida.

Parmjit, S.; Sohal, Nickie E.; BARA Cost and Tomas, M. (1992):Dietary W3 fatty acid alter prostaglandin synthesis, glucose transport and protein turnover in skeletal muscle of healthy and diabetic rats. Biochem,J. 286: 405-411.

Randel, R.D. (1990):Nutrition andpostpartum rebreeding in cattle. J. Anim. Sci. 68: 853-866.

Short, R.E. and Adams, D.C. (1988): Nutritional and hormonal interrelationship in beef cattle reproduction. Can. J.Anim. Sci. 68: 29-37.

Snedecor, G.W. and Cochran, W. (1987):“statistical methods”8^th ed. Iowa, state univ. press, Ames, Iowa, USA.

Staples, C.R.; Burke, J. and Tnatcher, W.W. (1998): Influence of supplemental fats on reproductive tissues and performance of lactating cows. J. Dairy Sci. 81: 856-871.

Vazquez-Anon, M.; Nocek, J.; Bowman, G.; Hampton, T.; Atwell, C.; Vazquez, P. and Jenkins, T. (2008):Effects of feeding a dietary antioxidant in diets with oxidized fat on lactation performance and antioxidant status of the cow. J. Dairy Sci. 2008 Aug; 91(8): 3165-72.

Zcheng, R.A.; Roinson, R.S.; Puchpakumara, PGA. and Mansbridge, R.J. (2001):Effect of dietary polyunsaturated fatty acids on uterine prostaglandin synthesis in the cow. J. Endoc. 171: 463-473.

Xiang-Dong, Z. (2003):Reproduction in female yaks (Bosgrunnies) and opportunities for improvement. Theriogenology.59:1303-1321.