Effects of Intramuscular Vitamin E Administration on Chemical Composition of Lactating West African Dwarf (Wad) Goats Milk

Samson Adeoye (  adeolusambabs@yahoo.com ) Federal University of Agriculture Abeokuta https://orcid.org/0000-0003-1498-4365 Ikechukwu James Federal University of Agriculture, Abeokuta, Ogun State Emmanuela Nwosu Federal University of Agriculture Abeokuta James Daramola Federal University of Agriculture Abeokuta o. o Adewumi Federal University of Agriculture Abeokuta Akintayo Adelabu Federal University of Agriculture, Abeokuta


Introduction
Goat milk can serve as an alternative for rural households when cow milk is limited (Greyling, et al., 2004). Most local goat farmers may not be able to afford to keep exotic goat breeds for the purpose of milk production because of limited nance and the expertise to manage them in communal areas (Maphosa, et al., 2009). Goats in Africa are constantly exposed to adverse weather conditions which lead to production de ciencies. The herds of goats in Nigeria are majorly composed of local breeds which are constantly exposed to adverse effects of weather conditions, this culminates to poor health and low production. The supplementation of vitamin E has been used to improve the physiological status, reproductive performance and productivity (meat and milk) of ruminants especially sheep and cattle (Donnem et al., 2015 andVagni et al., 2011). Vitamin E is a free radical scavenger and also prevents lipid peroxidation thus, encouraging milk yield and reducing mastitis. The antioxidant property of vitamin E, supplied alone or together with Se, has been reported in dairy species on milk yield and quality (Politis, et al., 2004;Tufarelli and Laudadio, 2011). There is an increase in the milk production of cows supplemented with vitamin E during a short term, the reason is because of less udder infections (Chawla, and Kaur, 2004). A research carried out on dairy goats showed positive in uence of vitamin E and Se administration on milk yield, fat and protein contents (Tufarelli and Laudadio, 2011). There is paucity information about the use of vitamin E in goats contrary to much recorded in dairy cow and sheep production (Liu et al., 2013

Experimental does and management
Twenty-four lactating WAD does with ages ranging from one to three years were selected randomly for the study from existing ock. The goats were managed semi-intensively and were fed 0.5g concentrated feed per head per day with provision of clean water ad libitum. They were allowed to graze Panicum maximum eld from 10 am to 2 pm. The proximate composition of the formulated feed is shown in Table 1. The experimental station was kept clean and biosecurity protocols were observed such as adequate quarantine of new animals, proper medication and careful observation on the animals was done daily to prevent outbreak of disease.
Experimental design and procedure The twenty-four lactating (WAD) does were randomly assigned into three treatment groups of eight does each. Determination of milk composition of lactating West African Dwarf goats Milk protein was determined by Aldehyde method as described by Pyne (1932), Casein was gotten by burette reading (obtained from protein determination) multiplied by 1.38 as reported by Alganesh et al., (2007) and fat by Babcock method as reported by Herreid (2003). Ash content was determined by dividing weight of dried milk by weight of fresh sample of milk, and multiply all by 100. The solids-not-fat (SNF) of milk was determined by direct oven drying of milk sample minus ether extraction as described by Clark et al.(1989). Thus percentage values of protein plus ash was subtracted from percentage SNF to obtain percentage lactose (LAC) as described by Economides (1986). Total solid (TS) of milk samples was determined by direct oven drying method as described by Clark

Results
The average chemical composition of milk from WAD goat for the levels of vitamin E administrated is presented in Storage duration signi cantly (P<0.05) affected copper content of milk of lactating (WAD) does was. The means of the copper content increased inconsistently with the highest mean (0.25mg/100g) at twelfth week. Other minerals (Ca, P, Na, and Zn) were not signi cantly (P>0.05) in uenced by the storage duration but were available and stable.  Haenlein (1980). It was also found to be higher than the recommended values: 4.20% reported by the European Union Quality standard for unprocessed whole milk (Alganesh, 2016)  The signi cant decrease in the mean of milk calcium (Ca) and phosphorous (P) obtained after vitamin E administration is in accordance with the work of Murphy et al. (1980) who reported that higher levels of vitamin E supplementation reduced calcium and phosphorus in blood plasma, dry fat-free bone and bone ash in chicks. The calcium content of milk recorded (275.53, 183.57 and 257.63 mg/100g) in this current study, agreed with the range (86-1113 mg/100g) reported by Gajewska et al. (1997). However, the calcium in the milk recorded, is against the range 134.00-155.10, 120.63-132.57 and 130.28 mg/100g reported by (Alichanidis and Polychroniadou,1996); Recommended Daily Allowances-RDAs,2002and Soliman,2005) respectively. The phosphorous in the milk followed a similar trend like calcium and it was in line with the report of WHO / FAO (1996).

Discussion
There were consistent decrease in means of milk Ca, P, Zn and Cu as stage of lactation advanced and this could be due to normal phenomenon in milk yield of goats which determines the milk components qualities (Getaneh et al., 2016) The result of this study agreed with the report of (Mahmoud et al., 2014) who stated that as lactation progresses, the milk constituents decreased. The observation from this current study is comparable with the ndings of Schmidely et al. (2002) in Alpine and Saanen dairy goats who recorded the same trend for Ca and P during lactation period. The report of (Aganga et al., 2002;Assan, 2014) however disagrees with the observation of this current study, they reported that minerals uctuated throughout the lactation period in Tshwana goat. The mean of Cu component of the milk was inconsistent through the MSD and could be attributed to change and re-distribution of the trace element among its binding compounds which potentially affect its bioavailability. The mean of copper (0.25 mg/100gm) recorded at the end of MSD in this current study exceeds that (0.07 mg / 100 gm) reported by Sawaya et al. (1984) from fresh milk of Aardi and Masri goats of Saudi Arabia. The value was however lower to that (0.28 mg / L) reported by Akinsoyinu et al. (1979) from fresh milk of WAD goats.

Conclusion
Administration of vitamin E in this study improved the quality and stability of milk chemical compositions of lactating West African Dwarf does. Vitamin E can therefore be a bene cial supplement in milk production of goats in the tropical environment. Further studies are recommended with higher doses.

Declarations
Author contribution: Conceptualization, methodology, supervision, writing and review of the original draft: Samson Olubode Babalola Adeoye, Ikechukwu Joseph James.
Project supervision, review, and editing: Ikechukwu Joseph James, James Olamitibo Daramola. and Olajumoke Olusola Adewumi All authors read and approved the nal manuscript.
Data availability: The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.
Code availability: Not applicable.

Declarations
Statement of animal right: The research was conducted in accordance with applicable international, national and institutional guidelines for the care and use of animals.  3.00 ± 0.15 de