Milk composition Comparison between donkey, goat and cow breeds

Abstract

This study is interested in donkey's milk composition of Tunisian donkey breed. Milk composition of donkey population was compared with goat and cow breeds. Manual milking was carried out only once a day after separation of asses from their colt. Bovine milk was obtained from 73 animals (Holstein breed) reared in 5 private farms situated in kef, cows were mechanically milked. Goat milk was collected from 73 local Tunisian goat breed reared in 4 private farms situated in Kef. After milking, samples of a donkey, bovine, and goat milk were immediately cooled and transported, to the laboratory, under refrigerated conditions. Result showed that milk content varied significantly with breeds. Dray matter were 9.8 ± 0.56; 11.9 ± 0.5 and 12.1 ±1.1 respectively for donkey, cow and goat. Protein, lactose, fat and ash content for donkey were 1.49 ± 0.3; 6.07 ± 0.43; 1.3 ± 0.4 and 0.51 ± 0.05 respectively. Cattle milk content was higher than donkey and goat breeds. These parameters were 3.07 ± 0.2; 5.02±0.12; 3.6±0.4 and 0.74 ±0,02 for Protein, lactose, fat and ash. Goat analysed milk showed 3.01 ± 0.3; 4.5 ± 0.4; 5.04 ±1.7 and 0.85± 0.009 for Protein, lactose, fat and ash. This species can play key economic potential for Tunisian farmers in the future.

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Volume 9 (5). Published September, 15, 2018
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E-ISSN 2286-5314
AROUA et al. (2018) / Journal of new sciences, Sustainable Livestock Management, 9 (5), 202-206 202
Milk composition Comparison between donkey, goat and cow
breeds
M. AROUA1, B. JEMMALI2, S. BEN SAID 4, I. TOUATI1, M. MAHOUACHI4
1 Institut National Agronomique de Tunis
2 ADIPARA Lab, Ecole Supérieure d’Agriculture de Mateur, Université de Carthage, Carthage, Tunisia
3 Laboratoire d’Analyse Génétique Animale, Institut de la Recherche Vétérinaire de Tunisie, Tunis,
Tunisia
4 Ecole Supérieure d’Agriculture du Kef, Université de Jendouba, Tunisia
*Corresponding author: arouamohamed2310@gmail.com
Abstract – This study is interested in donkey‘s milk composition of Tunisian donkey breed. Milk
composition of donkey population was compared with goat and cow breeds. Manual milking was carried
out only once a day after separation of asses from their colt. Bovine milk was obtained from 73 animals
(Holstein breed) reared in 5 private farms situated in kef, cows were mechanically milked. Goat milk
was collected from 73 local Tunisian goat breed reared in 4 private farms situated in Kef. After milking,
samples of a donkey, bovine, and goat milk were immediately cooled and transported, to the laboratory,
under refrigerated conditions. Result showed that milk content varied significantly with breeds. Dray
matter were 9.8 ± 0.56; 11.9 ± 0.5 and 12.1 ±1.1 respectively for donkey, cow and goat. Protein, lactose,
fat and ash content for donkey were 1.49 ± 0.3; 6.07 ± 0.43; 1.3 ± 0.4 and 0.51 ± 0.05 respectively.
Cattle milk content was higher than donkey and goat breeds. These parameters were 3.07 ± 0.2;
5.02±0.12; 3.6±0.4 and 0.74 ±0,02 for Protein, lactose, fat and ash. Gaot analysed milk showed 3.01 ±
0.3; 4.5 ± 0.4; 5.04 ±1.7 and 0.85± 0.009 for Protein, lactose, fat and ash. This species can play key
economic potential for Tunisian farmers in the future.
Keywords: milk, characteristics, donkey, goat, cow.
1. Introduction
The donkey is native to northeastern Africa, it is domesticated in Egypt around 4000-5000 BC and in
the Middle East around 100 BC (Beja-Pereira et al. 2004; Clutton-Brock 1999; Epstein 1984). For a
long time, the donkey occupies a social, economic, cultural and medicinal importance , from where in
Africa, it is used for the transport of the people and the goods search for water point, agricultural work
(Doutressoulle 1947; ROAMBA 1990; Tapsoba 2012)and also for treatment of several diseases like
(whooping-cough, hemorrhoid) )(Bernus 2013), it is for this reason in kabylie they respect donkeys and
refuse to mistreat them . Donkeys milk was used as a breast milk substitute because for their similar
nutritional composition especially low casein content(Vincenzetti et al. 2005), and high content of
lysozyme 1 mg/l(Vincenzetti et al. 2005). It is more and more used to nourish allergic kids to cow milk
(Carroccio et al. 2000; Lauzier 2011). Recently, some researchers show the effects of donkey’s milk on
atherosclerosis prevention (Tafaro et al. 2007),they also prove that it has an antibacterial,
antiviral(Brumini et al. 2013; Vincenzetti et al. 2005), and antitumor effect(Mao et al. 2009). Finally,
donkey milk is highly used for cosmetic reasons.
In Tunisia, the donkey was used in farms for agricultural work. Donkey’s milk has not been valorized
yet. National statistics (ONAGRI 2018) show a headcount of 123000 unequally distributed in Tunisian
territory; in fact, mountainous, borders and center regions hold the majority of a donkey.
Few studies concerning this theme have been carried out such as (Sana 2005) which is interested in the
phenotypic characterization of donkey breeds in Tunisia, (Charfi et al. 2018) has studied the
microbiological quality of Arabian donkey milk. So, it seems important to focus on this species that
seems to be an economic potential for Tunisian farmers in the future. For this reasons, this study is
interested in donkey‘s milk composition of Tunisian donkey breed.

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AROUA et al. (2018) / Journal of new sciences Sustainable Livestock Management, 9(5), 202-206 203
2. Materials and Methods:
2.1. Milk samples
Donkey milk was collected from 73 local Tunisian donkeys aged between 8 and 10 years reared in 3
Tunisian regions (Kef, Zaghouan,Kasserine ). Manual milking was carried out only once a day after
separation of asses from their colt. Bovine milk was obtained from 73 animals (Holstein breed) reared
in 5 private farms situated in kef, cows were mechanically milked. Goat milk was collected from 73
local Tunisian goat breed reared in 4 private farms situated in Kef. After milking, samples of a donkey,
bovine,and goat milk were immediately cooled and transported to the laboratory under refrigerated
conditions.
2.2. Chemical composition
The pH was measured by a pH meter (Model , HI98107 pHep) Dry matter, Protein, Fat, Ash,Lactose,
Density and freezing point were analyzed using an automatic milk analyzer device “ Lactoscan “
calibrated to donkey, cow and goat milk.
2.3. Statistical analysis:
After data collection and processing, different statistical tools were used, all data was processed by using
Microsoft excel 2007 software.Results were analyzed using one-way ANOVA to verify therepeatability
of every parameter result. These analyses werecarried out usingXlstat(Addinsoft 2013). To compare
between each mean value parameter of donkeymilk, bovine milk and goat milk data were subjected to
Student’s t-test.The statistical significance of the relationship was analyzedat the 95% confidence level
and evaluated by the Pvalue.
3. Results And Discussion
3.1. Milk composition
Result showed that milk content varied significantly with breeds. Dray matter were 9.8 ± 0.56; 11.9 ±
0.5 and 12.1 ±1.1 respectively for donkey, cow and goat. Protein, lactose, fat and ash content for donkey
were 1.49 ± 0.3; 6.07 ± 0.43; 1.3 ± 0.4 and 0.51 ± 0.05 respectively. Cattle milk content was higher than
donkey and goat breeds. These parameters were 3.07 ± 0.2; 5.02±0.12; 3.6±0.4 and 0.74 ±0,02 for
Protein, lactose, fat and ash. Gaot analysed milk showed 3.01 ± 0.3; 4.5 ± 0.4; 5.04 ±1.7 and 0.85±
0.009 for Protein, lactose, fat and ash.
The observed average of donkey milk dry matter content (Tab1 ) (9.8%) was higher than data reported
by (Ivanković et al. 2009; Salimei et al. 2004) respectively (8.8 %, 8.48% ) and lower than data for dry
matter content (10.8%) reported by (Oftedal and Jenness 1988), this level of donkey milk dry matter is
significantly (p<0.0001) lower than cow and goat milk (fig 1) .
The observed average of milk fat content (Tab1) (1.3 ± 0.4 %) was found to behigher than values
reported by (Guo et al. 2006)and (Ivanković et al. 2009) respectively ( 1.15%, 0.22%).It remained lower
than data reported by (Oftedal and Jenness 1988) (1.82%) and higher than the value reported by
(Ivanković et al. 2009) respectively (0.22%),compared to goat and bovine milk (Fig 1 ) Fat content
donkey milk shows a lower fat content(p<0.0001) for this reasons, it was recommendedin diet therapy
to prevent cardiovascular, autoimmune and inflammatory diseases(Martemucci and D’Alessandro
2012).
The observed average milk protein contentof Tunisian donkeys breed (Tab1) (1.49%) was similar to
the data protein content 1.5% proved by (Ivanković et al. 2009) for the littoral Dinaric asses and it was
lower than values reported by (Salimei et al. 2004) and (Giosuè et al. 2008) respectively
(1.72%,1.89%).According to most authors, the composition of protein content varies considerably
among species and is influenced by breed, stage of lactation, feeding, climate, parity, season and udder
health status (Gubić et al. 2015). The protein content of donkey milk was significantly (p<0.0001) lower
than cow and goat milk (Fig1).
The average lactose contentof Tunisian donkeys breed (Tab1) (6.07 ± 0.41%) was lower than content
found by (Guo et al. 2006; Ivanković et al. 2009; Salimei et al. 2004) ,Donkey milk lactose is
significantly higher than cow and goat milk (Fig 1) (p<.0001) ( Fig1 ). In fact,the high lactose level is
responsible for the good palatability of milk and facilitates the intestinal absorption of calcium that is
essential for Infant’s bone mineralization. Lactose gives good taste to donkey milk (Monti et al. 2007)
and is also a precious source of galactose, essential for the development of the nervous system.

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Compared withgoat and bovine milk, donkey milk presents high lactose content, therefore it’s as
inadequate for people suffering from lactose intolerance (Heyman 2006).
Basedon protein and lactose content similar to human milk (Salimei et al. 2004),donkey milk could be
better substitute for the breastmilk compared to bovine and goat milk.
Table 1. Physicochemical characteristics of Tunisian donkey milk compared to bovine and goat milk
Donkey milk
Bovine milk
Goat milk
Dry matter (%)
9.8 ± 0.56
11.9 ± 0.5
12.1 ±1.1
Protein (%)
1.49 ± 0.3
3.07 ± 0.2
3.01 ± 0.3
Lactose (%)
6.07 ± 0.43
5.02 ± 0.12
4.5 ± 0.4
Fat (%)
1.3 ± 0.4
3.6 ± 0.4
5.04 ± 1.7
Ash (%)
0.51 ± 0.05
0.74 ± 0,02
0.85 ± 0.009
Fig 1. Variation of the chemical composition of donkey, goat and cow milk
Donkey milk had a freezing point value of -0.510, which was significantly (P ≤ 0.0001) higher than that
of bovine milk -0.520 (°C) and goat milk -0.555 (°C) (Fig 2). This result can be explained by the dry
matter content of asses milk, which was lower compared to cow and goat milk .In fact ,milk freezes at
a temperature slightly lower than water, because of the presence of soluble constituents such as lactose
and soluble salts; the freezing point of milk depends on the molar concentration of its soluble, low
molecular weight compounds (Acharya et al. 2006; Charfi et al. 2018).
Fig 2. Variation of freezing point values of donkey, goat and cow milk
0
2
4
6
8
10
12
14
Fat (%) Protein (%) Lactose (%) Dry matter (%)
Goat milk
cow milk
donkey milk
-0,56
-0,54
-0,52
-0,5
-0,48
Goat milk Cow milk Donkey milk
Temperature (°c)
Variaton of freezing point values of donkey , goat and
cow milk
Freezing point (°C)

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The pH measurements performed on a donkey, goat,and bovine milkshowed that donkey milk had higher
neutral pH (7.09) compared to bovine milk (6.65) and goat milk (6.5) (Fig 3).This difference was
explained by the lower levels of caseins, phosphate, citrates and initial lactic acids present in donkey
milk (Charfi et al. 2018).
Fig 3. Variation of pH values of donkey, cow and goat milk
4. Conclusion
Result showed that milk content varied significantly with breeds. Dray matter were 9.8 ± 0.56; 11.9 ±
0.5 and 12.1 ±1.1 respectively for donkey, cow and goat. Protein, lactose, fat and ash content for donkey
were 1.49 ± 0.3; 6.07 ± 0.43; 1.3 ± 0.4 and 0.51 ± 0.05 respectively. Cattle milk content was higher than
donkey and goat breeds. These parameters were 3.07 ± 0.2; 5.02±0.12; 3.6±0.4 and 0.74 ±0,02 for
Protein, lactose, fat and ash. Gaot analysed milk showed 3.01 ± 0.3; 4.5 ± 0.4; 5.04 ±1.7 and 0.85±
0.009 for Protein, lactose, fat and ash.
Donkeys can play a vital role in the Tunisian economy. Nowadays, for its multidisciplinary use such as
cosmetics, medicinal and health issues donkey milk become more and more sought-afterwhich makesthe
research of their production possibilities reasonable.Further research of milkproduction and
functionality and production technology will help in a more completeutilization of Tunisian donkey.
5. References
Acharya, P. S., Zukas, A., Chandan, V., Katzenstein, A.-L. A. and Puré, E. 2006. Fibroblast
activation protein: a serine protease expressed at the remodeling interface in idiopathic pulmonary
fibrosis. Human pathology 37(3):352-360.
Addinsoft, X. 2013. Data analysis and statistics software for Microsoft Excel. Addinsoft, New York.
Beja-Pereira, A., England, P. R., Ferrand, N., Jordan, S., Bakhiet, A. O., Abdalla, M. A.,
Mashkour, M., Jordana, J., Taberlet, P. and Luikart, G. 2004. African origins of the domestic
donkey. Science 304(5678):1781-1781.
Bernus, E. 2013. L aits touaregs. Ressources vivrières et choix alimentaires dans le bassin du lac
Tchad:399.
Brumini, D., Furlund, C. B., Comi, I., Devold, T. G., Marletta, D., Vegarud, G. E. and Jonassen,
C. M. 2013. Antiviral activity of donkey milk protein fractions on echovirus type 5. International
Dairy Journal 28(2):109-111.
Carroccio, A., Cavataio, F., Montalto, G., D'amico, D., Alabrese, L. and Iacono, G. 2000.
Intolerance to hydrolysed cow's milk proteins in infants: clinical characteristics and dietary
treatment. Clinical & Experimental Allergy 30(11):1598-1603.
Charfi, I., Rezouga, F., Makhlouf, A. and Bornaz, S. 2018. The behaviour of Arabian donkey milk
during acidification compared to bovine milk. International Journal of Dairy Technology 71(2):439-
445.
Clutton-Brock, J. 1999. A natural history of domesticated mammals. Cambridge University Press.
6,3
6,4
6,5
6,6
6,7
6,8
6,9
7
7,1
7,2
Donkey milk Cow milk Goat milk
pH

Volume 9(5). Published September, 15, 2018
www.jnsciences.org
E-ISSN 2286-5314
AROUA et al. (2018) / Journal of new sciences Sustainable Livestock Management, 9(5), 202-206 206
Doutressoulle, G. 1947. L'élevage en Afrique occidentale française. Larose.
Epstein, H. 1984. Ass, mule and onager. Evolution of domesticated animals/edited by Ian L Mason.
Giosuè, C., Alabiso, M., Russo, G., Alicata, M. and Torrisi, C. 2008. Jennet milk production during
the lactation in a Sicilian farming system. Animal 2(10):1491-1495.
Gubić, J., Milovanović, I., Iličić, M., Tomić, J., Torbica, A., Šarić, L. and Ilić, N. 2015. Comparison
of the protein and fatty acid fraction of Balkan donkey and human milk. Mljekarstvo/Dairy 65(3).
Guo, R., Sun, D., Tan, Z., Rong, D. and Li, C. 2006. Two recessive genes controlling
thermophotoperiod-sensitive male sterility in wheat. Theoretical and applied genetics 112(7):1271-
1276.
Heyman, M. B. 2006. Lactose intolerance in infants, children, and adolescents. Pediatrics 118(3):1279-
1286.
Ivanković, A., Ramljak, J., Štulina, I., Antunac, N., Bašić, I., Kelava, N. and Konjačić, M. 2009.
Characteristics of the lactation, chemical composition and milk hygiene quality of the Littoral-
Dinaric ass. Mljekarstvo/Dairy 59(2).
Lauzier, A.-C. 2011. Pratiques d'allaitement à Port-Royal et aux Enfants-Assistés à la fin du XIXe
siècle. Mémoire pour le diplôme d'Etat de sage-femme, Faculté de médecine de Paris, Ecole de Sage-
femme de Baudelocque.
Mao, X., Gu, J., Sun, Y., Xu, S., Zhang, X., Yang, H. and Ren, F. 2009. Anti-proliferative and anti-
tumour effect of active components in donkey milk on A549 human lung cancer cells. International
Dairy Journal 19(11):703-708.
Martemucci, G. and D’Alessandro, A. G. 2012. Fat content, energy value and fatty acid profile of
donkey milk during lactation and implications for human nutrition. Lipids in health and disease
11(1):113.
Monti, G., Bertino, E., Muratore, M. C., Coscia, A., Cresi, F., Silvestro, L., Fabris, C., Fortunato,
D., Giuffrida, M. G. and Conti, A. 2007. Efficacy of donkey's milk in treating highly problematic
cow's milk allergic children: an in vivo and in vitro study. Pediatric Allergy and Immunology
18(3):258-264.
Oftedal, O. T. and Jenness, R. 1988. Interspecies variation in milk composition among horses, zebras
and asses (Perissodactyla: Equidae). Journal of Dairy research 55(1):57-66.
ONAGRI,2018.http://www.onagri.nat.tn/uploads/divers/enquetesstructures/section_11.htm#_Toc1245
59925.[Online]Available:http://www.onagri.nat.tn/uploads/divers/enquetesstructures/section_11.ht
m#_Toc124559925.
Roamba, C. R. 1990. Caractérisation morphobiométrique et biochimique des asins (Equus asinus) du
Sénégal. UNIVERSITE CHEIKH ANTA DIOP DE DAKAR.
Salimei, E., Fantuz, F., Coppola, R., Chiofalo, B., Polidori, P. and Varisco, G. 2004. Composition
and characteristics of ass's milk. Animal Research 53(1):67-78.
Sana, Z. 2005. Caractérisation phénotypiques des ânes en Tunisie.
Tafaro, A., Magrone, T., Jirillo, F., Martemucci, G., D'alessandro, A., Amati, L. and Jirillo, E.
2007. Immunological properties of donkey's milk: its potential use in the prevention of
atherosclerosis. Current pharmaceutical design 13(36):3711-3717.
Tapsoba, M. 2012. Aspects socio-économiques de l’âne, les pathologies dominantes et leur prise en
charge au Burkina Faso. Thèse Méd Vét Dakar 16:165.
Vincenzetti, S., Polidori, P., Fantuz, F., Mariani, P., Cammertoni, N., Vita, A. and Polidori, F.
2005. Donkey’s milk caseins characterization. Italian Journal of Animal Science 4(sup2):427-429.