Effect of Addition of Pomegranate Peel in the Ration with or Without Polyethylene Glycol on Productive Performance of Lactating Goats

Pomegranate juice processing industries generate enormous waste in the form of peel that has been suggested and evaluated as a supplement in animal feed but pomegranate peel have high percent of tannins, So the purpose of this paper was to estimate the effect of addition of pomegranate peel (PP), detanninated pomegranate peel (DPP) and pomegranate peel with polyethylene glycol (PEG) on nutrients digestibility, goats milk yield and its composition, feed conversion and some blood parameters. Also, simple economic evaluation of the tested rations was considered.Sixteen lactating Zaraibi goats of about 3-4 years old (in their 2 nd to 4 th of lactation seasons with an average body weight of about 25 + 0.5 kg were used in the present study. After 14 days of parturition was randomly assigned into four groups, four animals per each tested ration (R) for 90days, R 1 : Control : 50% CFM + 25% Egyptian clover and 25% wheat straw, R 2 : Control ration+1% PP, R 3 : Control ration+1% PP + 20 g (PEG) and R 4 :Control ration+1% DPP. The results revealed that the PP contained 90.85% DM, 4.84% CP, 15.53% CF, 87.21%OM, 4.69% EE, 62.15% NFE and 15.28% tannins. No signicant differences were found between the tested rations regarding nutrients digestibility except EE digestibility. Nutritive values of R 2 and R 3 were slightly higher than R 4 and R 1 , respectively. Ration three (R 3 ) was the best ration for daily milk yield and total milk yield, where R 4 showed the worst one. Also, there are no signicant differences for dry matter, SV and TDN intake. While, values of DCP intake were higher signicantly (P<0.05), for R 3 and R 2 followed by R 4 then R 1 . Regarding feed conversion, R 4 was superior to other tested rations followed by R 1 then R 3 followed by R 2 . All blood serum parameters were in the normal rang which support that the healthy effect of tested additives in goats rations.


Introduction
Pomegranate (Punica granatum L.) belongs to the Punicaceae family (Miguel et al., 2010) and is popularly consumed as fresh fruit, drinks, food items and extracts that are used in herbal remedies and dietary supplements as botanical ingredients. Fruit (peel, seeds and juice) is the main source of dietary pomegranate phytochemicals (Mars and Marrakchi, 1999). Pomegranate peel can be regarded as a waste from the pomegranate industry, producing comparatively higher polyphenol levels compared to fruit juice or to Christaki et al. )2011( and Prakash and Prakash )2011), so average production of pomegranates peel amounted to190.5-255.27thousand ton in 2016/2017. Hussein and Shujaa (2013a) and HamaKhan et al. (2015) showed that effect of antioxidant levels in pomegranate peel in lambs fed helps to improve their health and animal performance. Also, Abarghuei et al., (2013) indicated that cows fed 800 ml pomegranate peel extract in their diet were signi cantly increased in milk yield.
High intakes of tannins have a direct negative impact on productivity; the availability of nutrients is reduced due to the complexes formed between tannins and many forms of macromolecules, voluntary consumption of feed and digestibility are reduced, the animal's digestive physiology may be compromised, and mucosal disturbances may occur, etc. (Addisu, 2016), but, In any case, it is increasingly recognised that the quantity consumed is important because tannins in many forage types can have bene cial effects in moderate quantities (Waghorn and Mcnabb, 2003).
Polyethylene glycol (PEG) is a polymer that irreversibly binds tannins, reducing the harmful food intake effects of tannins (Silanikove et al., 1994), digestibility (Silanikove et al., 1996), and preferences (Titus et al., 2001). So we used detanninated pomegranate peel and polyethylene glycol ( PEG) as a tannin-binding agent in current research to decrease the impact of polyphenolic compounds.
The purpose of this research was to estimate the effect of addition of pomegranate peel (PP), detanninated pomegranate peel (DPP) and pomegranate peel with polyethylene glycol (PEG) on nutrients digestibility, goats milk yield and its composition, feed conversion and some blood parameters. Also, simple economic evaluation of the tested rations was considered.

Materials And Methods
The present research was carried out at the Experimental Farm and Laboratories of Animal Production Department -Faculty of Agriculture -Fayoum University, Egypt, during April to June, 2019.
Preparation of pomegranate peel and detanninated pomegranate peel Dried pomegranate peels were acquired from the by-product unites in Fayoum, Egypt. Peels were crushed in a grinder to reduce it to coarse size peel. Detanninated pomegranate peel prepared according to (Kushwaha et al., 2013), Both detanninated and dried pomegranate peel powder transferred in polyethylene bags for chemical analysis and in farm trial.

Experimental animals
Sixteen lactating Zaraibi goats of about 3-4 years old (in their 2nd to 4th lactation seasons) with an average body weight of about 25 + 0.5 kg were used in the present study. After 14 days of parturition was randomly assigned into four groups, four animals per each tested ration (R) using complete randomized design.
Feeding and management of animals:-Animals were fed to cover their nutritional requirements according to NRC (1985). The concentrate feed mixture was offered with wheat straw daily at 8.00 am., then Egyptian clover offered once daily at 4.00 pm.
The 1% pomegranate peel 1% pomegranate peel + 20 g polyethylene glycol (PEG) and 1% detanninated pomegranate peel were introduced daily to each animal of second, third and fourth group with the concentrate feed mixture. Fresh water was available to the animals all the time. The experimental period was extended to 90 days.

Digestibility trial:
Digestibility trial was performed at the end of the lactation experiment, the nutrient digestibilities and feeding values were determined using acid insoluble ash (AIA) technique of Van Keulen and Young (1977).
Feces samples were collected daily per each animal for seven days, dried overnight in hot air oven at 60°C, weighted, ground through 1mm screen, then complete drying was undertaken at 105°C for 3hrs and weighted and stored in tight bottles for chemical analysis according to AOAC(2009).
Lactation trial:-After 14 days of the goat's parturition, milk yield was recorded during the last three days of each month for three months. Goats have been milked (hand milking) twice daily at 7:00 am and 7:00 pm by milking one teat while, the other one was lift to lamb for suckling according to Farag (1979). Milk samples were stored in bottles (100 ml) and frozen at (-20 o C) till the chemical analysis.
Sampling of blood:-Blood samples were collected at the end of lactation trial (90 day) before morning feeding. A sample of 10 ml of blood per animal was collected from the jugular vein in dry clean glasses tubes. Blood samples were centrifuged for 20 minutes at 3500 rpm to obtain serum. Serum was separated into a clean dried glass vial and stored at -18°C for chemical analysis.
Methods of analysis:-Feeds and feces analysis:-Chemical analysis of feedstuffs and feces samples were carried out to determine the percentage of dry matter (DM), crude protein (CP), ether extract (EE), crude ber (CF) and ash content according to methods of AOAC (2009). The nitrogen free extract (NFE) was calculated by difference. Neutral detergent ber (NDF), acid detergent ber (ADF) and acid detergent Lignin (ADL) were determined according to Goering and Van Soest (1970). The tannin contents were determined by Folin Denis reagent as described by Makkar et al.

Statistical analyses:
Statistical analyses were conducted by the general linear model procedure adapted by SPSS (2007) according to the following model: Where: Y ij, is the dependent variable, µ is the overall mean, T i, is the effect of treatment and e ij, is the residual error. Duncan's multiple test (Duncan, 1955) was carried out to separate among means.

Simple economic evaluation
Economic return of the tested rations were calculated assuming that the price of one kg of raw milk was 7 L.E. and the cost of one ton DM of Egyptian clover, corn, wheat bran, soybean meal, wheat straw and Pomegranate Peel were 2500, 4100, 3900, 6700, 1000, and 500 L.E, respectively and the price of one Kg Polyethylene glycol was 950 L.E.

Results And Discussion
Chemical composition of feed ingredients Chemical composition of feed ingredients is presented in Table ( (28.54%), ADF (26.11%) and lignin (7.59%). Higher chemical compositions in DPP than PP indicated that retention and accumulation of the above compositions during the detannination process but in case of lower test values in DPP than PP indicated that losses of the above components during the detannination process. The summative analysis of concentrate feed mixture; Egyptian clover and wheat straw were in the common range.
Digestibility and nutritive values of tested rations Date in Table (2) presented the average values of digestibility coe cients and nutritive values of the tested rations. No signi cant differences were found between the tested rations regarding nutrients digestibility except EE digestibility, where R 2 , R 3, and R 4 were superior to R 1 . The result indicated that CP and CF digestibilies were the highest in R 3 compared to other treatment groups. Furthermore, the mean value of OM and EE digestibilies were the highest value was found in R 2 . Also, DM digestibility was higher value in R 2 , R 3, and R 1 than R 4 .While, NFED showed higher digestibility in control group (R 1 ) followed by R 2 , R 3 , and R 4 .  2012) found that using pomegranate peel improved the digestibility of nutrients in diets compared to the control treatment. These researchers pointed out that improvement in digestibility might be due to the added nutritive value of the PP extract itself and low and moderate (2% − 4.5%) concentrations of condensed tannins in the diet improved production e ciency in ruminants, by increasing the ow of non-ammonia nitrogen and essential amino acids from the rumen. In ruminants, a particularly important positive effect of tannins is dietary protein protection from ruminal micro ora attack (McNabb et al. 1996). The high digestibility of ether extract (EED) was found in lambs fed 4% PP, due to tannin was protected the ether extract to degrade in the rumen and it escapes and ow rate from rumen into the small intestine and it is more suitable for absorption (Patra and Saxena, 2011). These ndings may support the obtained results of EE digestibility.  2013) reported that dietary inclusion of tannin-rich pomegranate peel extract (up to 1200 mg/day) had no effect on the digestibility of DM, OM, NDF, and ADF in dairy cows. The inconsistency among these works may be associated with differences among studies, in the diets used as well as the differences in the amount and type of pomegranate (i.e., the concentration and nature of the active ingredients), and type of experimental animals, all which can affect digestibility.
Data in Table (2) cleared that no signi cant differences were obtained between the tested rations for SV, TDN, DCP, DE, ME and NE L .
The R 2 and R 3 were recorded slightly higher of SV, TDN, and DCP than R 4 and R 1 . The increases in TDN, SV, and DCP value for R 2 and R 3 may re ect the results of digestibility coe cients of CP, EE, CF, and NFE.
Digestible energy (DE), metabolizable energy (ME) and net energy for lactation (NE L ) were deceased with R 1 and R 4 compared with R 2 , and R 3 . The results that obtained by Sadq et al. (2015) in this regard may support our ndings they found that the higher TDN, DE, and ME are increased in lambs fed 1% PP compared to lambs fed 0, 2, and 4%.

Milk yield and milk composition
Overall mean values of milk yield and composition are presented in Table (  These results are agreement with those obtained by Safari et al., (2018) found that there is no effect of the supplementing diet containing pomegranate seed and peel on milk ash % and increased milk ash yield of dairy cows, but Kotsampasi et al., (2017) who reported that the addition 75 of pomegranate pulp silage in the diet of dairy cows decreased milk ash % and there is no effect on milk ash yield.
Such nding differences may support the different animal breed and methodology of pomegranate prepared.
Data exhibited in Table (4) showed that overall mean values of milk yield and composition in the different lactation periods Regarding the effect of milking period, data showed increasing milk yield and FCM from P I to P Π and then decreasing in P III . There are signi cant differences for milk yield between periods of lactation for each ration. Period Π showed the highest yield, but P III was the lowest one, Abedo et al., (2013) found the same trend with advance of lactation. Concerning the results of the effect of milking period on milk fat %, it was clear that highest value signi cantly (p ≤ 0.05) was found with P I and P III compared to P II . Such differences may also re ex the milk yield results, while there are no signi cant differences (p > 0.05) for milk fat yield.
Data showed that there are signi cant differences for milk total solids % and milk total solids yield between periods of lactation, where the values of milk total solids % of P Π and P III were higher than P I; and the value of milk total solids yield of P Π was higher than P I and P III . The values of milk total solids % were 14.13, 14.45, and 14.44(g/head/day) for P I , P Π and P III , respectively. Also, there are signi cant differences for both milk SNF %, milk SNF yield, milk TP %, milk TP yield, milk lactose %, milk lactose yield, milk ash % and milk ash yield between periods of lactation, where the values of milk solids not fat % and milk solids not fat yield of P II were higher than and P I and P IΠ .

Milk radical scavenging activity
There are no signi cant differences (p > 0.05) for antioxidant activity between the tested rations Table (

Feed intake and feed conversion
There are no signi cant differences for dry matter and energy intake (SV, and TDN) of the tested rations

Some blood serum parameters
No signi cant differences were found between the tested rations for serum total protein, albumin and globulin Table (7), where all values of them were within the normal range (6.1-7.5, 2.3-3.6 and 2.7-4.4 g/dl, respectively) as found by Boyd (2011). Generally no changes in the blood metabolites (serum albumin, total protein and globulin) suggested that damage to the liver did not occur. These results are an agreement with Hatami et al., (2018) who found that the addition of PEG to the PP diets has no effect on plasma albumin and total protein concentration. However, Safari et al., (2018) indicated that the level of albumin and total protein was lower for cows fed pomegranate by-products than control during postpartum. Also, Khan et al., (2015) found that no signi cant difference was found in total protein level between control and groups fed PP, while was found increased in albumin level in tested groups compared to the control.
The result indicated that the differences between rations for serum urea and creatinine Table (7) were not signi cant. The values of serum urea and creatinine were within the normal range (10-50 mg/dl) as reported by Kaneko (1989) and (0.7-1.5 mg/dl) as noticed by Boyd (2011), respectively. Such nding may suggest no negative effect on goat kidneys. Also, it was clear that no signi cant differences were obtained regarding serum glucose   ., 2008). These results of serum AST and ALT were similar to those obtained by Hatami et al., (2018) who found that the addition of PEG to the PP diets has no effect on plasma AST and ALT concentration. However, Safari et al., (2018) indicated that the level of AST was lower for cows fed pomegranate by-products than control during postpartum. Also, Ramzi, (2016) indicated that the level of AST was highest in lambs fed PP than the control, while ALT level was highest in lambs of the control compared to groups that fed PP in the diet. Such differences may support the effect of animal breed.
There were no signi cant differences among all groups in the overall means of serum cholesterol, triglyceride, HDL, LDL, and LDL/HDL ratio Table (7). The obtained results of lipid pro les were similar to Hussein and Shujaa (2013b) they reported that the addition of PP in the diet of Awassi had no effect on cholesterol, and triglyceride concentration. On the other hand, Safari et al., (2018) indicated that the level of cholesterol was lower for cows fed pomegranate by-products than control during postpartum, and Khan et al., (2015) found that total cholesterol and HDL concentration in lambs fed 1% PP were decreased, while triglyceride, LDL concentration, and LDL/HDL ratio increased compared to control group.
Simple economical evaluation of the tested rations Ration two (R 2 ) had higher net revenue and relative percentage of net revenue compared with other tested rations Table (8). The cost of feed consumed for R 3 was higher than the other tested rations because of the price of polyethylene glycol was higher, Moreover, R 3 showed negatively net revenue. Finally R 2 was the best one.

Conclusion
It seems that the rations containing pomegranate peel (R 2 ), and pomegranate peel with polyethylene glycol) R 3 ) could be used successfully for lactating goats since it improved feed intake, nutrients digestibility, milk yield and composition, but R 3 is very expensive compared with control one from economical point of view, R 3 showed negatively economical effect and not recommended.

Declarations
The contributions made by each listed author: Abdelkader Kholif was supervised the work, made statistical analysis and publishing the manuscript.