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1.
Cell Mol Biol (Noisy-le-grand) ; 69(13): 89-95, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38158683

RESUMO

Camel milk transformation into cheese remains an objective to be improved today. This study aimed to improve camel milk clotting using a crude extract from green pods of carob as a substitute for commercial rennet. The composition of the crude carob extract was determined for dry matter and protein content. Milk clotting conditions were studied at different temperatures, pH and CaCl2 concentrations. Milk clotting properties were assessed by milk clotting activity, specific activity and proteolytic activity. Enzymatic hydrolysis of camel milk caseins by crude carob extract and its inhibition were demonstrated by SDS-polyacrylamide gel electrophoresis. Crude carob extract analysis showed a protein and dry matter content of 23.26±0.5 mg/ml and 30.66±0.5 g/l, respectively. Optimal milk clotting activity was observed at 53.6 °C, pH 4.5, and 0.09 M CaCl2. The crude carob extract showed a high milk clotting activity (4.97 U/ml) and a low proteolytic activity (0.04U/ml) with camel milk. The cheese yield of curd produced from camel milk using crude carob extract was the highest (23.95%) compared with that of Camel chymosin (20.5%). The high ratio of milk-clotting to proteolytic activity shows the potential of this extract as a substitute for commercial rennet in the dairy industry.


Assuntos
Quimosina , Leite , Animais , Quimosina/análise , Quimosina/química , Quimosina/metabolismo , Leite/metabolismo , Camelus/metabolismo , Cloreto de Cálcio/análise , Cloreto de Cálcio/metabolismo , Cloreto de Cálcio/farmacologia , Concentração de Íons de Hidrogênio
2.
Cell Mol Biol (Noisy-le-grand) ; 68(7): 194-199, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-36495496

RESUMO

This study aimed to evaluate the effect of various heating temperatures on the antioxidant activities of camel milk caseins. The samples were processed with three different heat treatments: Pasteurization at low and high temperatures and boiling. Fresh camel milk (unheated) was used as a control. Camel milk caseins were separated by fast ion exchange liquid chromatography (FPLC) and identified by the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS page). The antioxidant activities of caseins were measu- red by three different in vitro methods: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, 2, 2'-azino-bis (3-ethylbenzthiazoline-6-sulfonate) (ABTS) radical scavenging activity and ferric reducing power assay (FRAP). The antioxidant activity evaluated by the DPPH assay decreased significantly (p<0.05) with the increase in heat treatment of caseins. However, there was no significant difference in ABTS radical scavenging activity and Ferric Reducing Antioxidant Power assay (FRAP) of heat-treated camel caseins compared to unheated onesStill, a decrease was observed in those activities by the increase of temperature in the different casein concentrations. Besides, whatever the concentration tested and the methods applied, the antioxidant activity of beta-casein (ß-CN) was more pronounced than the alpha-casein (α-CN). Therefore, camel milk casein could be used as a natural source of antioxidants which may have a potential application in the food and nutraceutical industries. Throughout the different heat treatments applied, pasteurization at low temperature could be the most suitable alternative to preserve the antioxidant properties of camel milk.


Assuntos
Caseínas , Leite , Animais , Antioxidantes/química , Camelus , Temperatura Alta
3.
Anim Biotechnol ; 32(6): 748-757, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32293994

RESUMO

Healthy animals can constitute a reservoir for Escherichia coli potentially dangerous for humans. Our objectives were to investigate virulence genes in E. coli isolated from healthy animals in southern Tunisia and to determine their resistance to antimicrobials of high importance in humans and animals. 126 fecal samples were collected from healthy animals (cattle, sheep, goats, chicken, camel, bustard and rabbit) and assayed by PCR for virulence genes and by disk diffusion for antimicrobial resistance. STEC were isolated most frequently from goats (27.7%), sheep (20%) and cattle (14.2%). ExPEC prevalence of iucD (41.6%), papC (27.7%), sfa (13.8%), afa8 (13.8%) and iron (72.2%) was highest in camels. Prevalence of the ExPEC associated genes iss and cnf and the EPEC defining gene eae was highest in rabbits (53.3, 13.3, and 53.3%, respectively). The genes defining enterotoxigenic, enteroinvasive and enteroaggregative E. coli were not detected and faeG was found only in camels (5.5%). The most common phylogenetic groups were B1 (54.5%) and B2 (16.6%). Virulence gene profiles varied greatly between animal species. Overall, antimicrobial resistance was not highly prevalent, the highest resistance being observed against tetracycline, 43.9%.


Assuntos
Antibacterianos/farmacologia , Escherichia coli , Gado/microbiologia , Animais , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Testes de Sensibilidade Microbiana , Filogenia , Ovinos , Tunísia/epidemiologia
4.
Trop Anim Health Prod ; 53(2): 275, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33880641

RESUMO

Effects of two different management systems on male dromedary camel hormones, behaviors, and semen parameters were documented. Camels (n=6) were tested under two management systems: (i) housed in single boxes with 1-h freedom (H23); (ii) exposed to females for 17 h (from 3.30 p.m. to 8.30 a.m.) and then housed (ConExF). Blood was collected every morning; camel behavior was recorded twice a day: (i) from 7:00 to 8:00 a.m. to determine the short effects; (ii) from 2:00 to 3:00 p.m. to determine the long effects. Each camel underwent a female parade and semen collection thrice a week; sexual behavior, libido, and semen parameters were assessed. Testosterone and cortisol concentrations were higher in ConExF than H23. Compared to the H23 group, ConExF group spent more time walking, standing tripods, and looking outside their pen/box but they spent less time eating, ruminating, resting, standing, and showing stereotypical behaviors. In the morning, ConExF group spent more time walking, ruminating, and showing typical sexual behaviors compared to themselves during afternoon time and the H23 group. However, in the afternoon time, ConExF camels put more time their heads outside the box through the window and showed higher frequencies of stereotypies, probably due to a higher level of frustration. While the sexual behavioral score was higher and ejaculates showed a higher fraction of milky white and white-colored semen in ConExF than H23 group, their libido was similar. Overall, 17 h of exposure led to an increase in testosterone and cortisol levels, enhancing sexual behavior and semen color, but leading to frustration.


Assuntos
Camelus , Análise do Sêmen , Animais , Feminino , Masculino , Sêmen , Análise do Sêmen/veterinária , Comportamento Sexual Animal , Testosterona
5.
J Food Sci Technol ; 58(5): 1727-1739, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33897011

RESUMO

This work intended to compare dromedary yogurt's characteristics obtained by a co-fermentation process with plant (carob powder) or autochthonous bacteria (Enterococcus faecium and Streptococcus macedonicus). For this reason, the ultrafiltration process (UF) is applied to increase the rate of total solids in dromedary milk within the margin needed to prepare a yogurt. Carob powder or autochthonous bacteria were incorporated at the level of 2% in UF milk. Then mixtures were fermented with the strains Lactobacillus bulgaricus and Streptococcus thermophiles, and the obtained products are named CFC (yogurt with carob), CFS (yogurt with autochthonous strains) and control (yogurt with only L. bulgaricus and S. thermophilus) respectively. All along of 3 weeks at cold, CFC and CFS maintained Streptococcus at appropriate levels (>8 log CFU/g). Moreover, CFC showed the lowest syneresis, highest cohesiveness and springiness values, and oleic acid (C18:1n9; 26.315%). However, CFS yogurt resulted in higher volatile compound formation than CFC and control, where isobornyl propionate was the major one.

6.
Food Technol Biotechnol ; 58(2): 147-158, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32831567

RESUMO

RESEARCH BACKGROUND: Milk protein hydrolysates have received particular attention due to their health-promoting effects. Dromedary milk differs from the milk of other dairy animals in the composition and structure of its protein components, which give it unique properties. The bioactivity and functionality of whole dromedary milk proteins and their enzymatic hydrolysates have not received much attention, hence this study aims to investigate the effect of enzymatic hydrolysis of dromedary milk proteins on their antioxidant activities and functional properties. EXPERIMENTAL APPROACH: Dromedary milk proteins were treated using four proteolytic enzymes (pepsin, trypsin, α-chymotrypsin and papain) and two mixtures of enzymes (pancreatin and pronase). The degree of hydrolysis was measured to verify the hydrolysis of the proteins. The sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and gel filtration chromatography served to determine the molecular mass distribution of the hydrolysates while reversed phase-high performance liquid chromatography (RP-HPLC) was conducted to explore their hydrophobicity. The antioxidant activities were evaluated using various in vitro tests, including 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging capacities, iron(III) reducing ability and chelating activity. Besides, functional properties such as solubility, foaming and emulsification were assessed. RESULTS AND CONCLUSIONS: Dromedary milk protein hydrolysates exhibited different degrees of hydrolysis ranging from 17.69 to 41.86%. Apart from that, the hydrolysates showed different electrophoretic patterns, molecular mass distribution and RP-HPLC profiles demonstrating the heterogeneity of the resulting peptides in terms of molecular mass and polarity. The hydrolysates displayed significantly higher antioxidant capacities than the undigested proteins at all the tested concentrations. Iron(II) chelating activity was the most improved assay after proteolysis and the hydrolysate generated with pancreatin had the highest chelating power. Dromedary milk protein hydrolysates possessed good solubility (>89%). Further, foaming and emulsifying properties of dromedary milk proteins were enhanced after their proteolysis. These interfacial properties were influenced by the enzymes employed during proteolysis. NOVELTY AND SCIENTIFIC CONTRIBUTION: Enzymatic hydrolysis of dromedary milk proteins is an effective tool to obtain protein hydrolysates with great antioxidant and functional properties. These results suggest that dromedary milk protein hydrolysates could be used as a natural source of antioxidant peptides to formulate functional foods and nutraceuticals.

7.
Trop Anim Health Prod ; 52(6): 3187-3194, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32642909

RESUMO

This study aimed to investigate the milk production potential and the impact of nongenetic factors on milk yield and composition of Tunisian dromedary camels. Milk recording and sampling were carried out at monthly intervals over complete lactation for 3 years from 95 camels reared in intensive and semi-intensive systems. The overall means of daily milk yield and fat, protein, total solids, and ash contents were 4.21 ± 1.98 l/day, 2.45 ± 0.9%, 2.67 ± 0.74%, 10.75 ± 1.41%, and 0.85 ± 0.08%, respectively. The total milk yield was 1388.41 ± 575.46 l/lactation for 11 months of lactation. The daily milk yield increased regularly throughout lactation until it reached its peak in the 4th month postpartum and then decreased until the 17th month postpartum. The chemical components, except ash, followed an opposite trend to the milk yield. Their minimum contents were recorded during the 7th and 8th months postpartum, while the maximum levels were observed during the 17th month postpartum. Regarding seasonal variation, the highest daily milk yield was recorded during summer (June), whereas the lowest was found in winter (December). In contrast, the maximum and minimum contents of fat and protein were observed during winter (December) and summer (July), respectively. Similarly, total solids content was maximum in January and minimum in August. Parity had no effect on daily milk yield, while all chemical components were higher in milk from primiparous than multiparous camels. Calf sex and management system did not affect the milk yield and composition. These results are useful in order to develop feeding strategies and breeding programs for improving milk production.


Assuntos
Camelus/fisiologia , Leite/química , Leite/metabolismo , Animais , Feminino , Lactação , Estações do Ano , Tunísia
8.
J Dairy Sci ; 102(6): 4844-4856, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31005319

RESUMO

The aim of this study was to explore the antibacterial peptides derived from dromedary lactoferrin (LFc). The LFc was purified from colostrum using a batch procedure with a cation exchange chromatography support and was hydrolyzed with pepsin to generate peptic digest. This peptic digest was fractionated by cation exchange chromatography, and the antilisterial activity of LFc, peptic digest, and obtained fractions was investigated using the bioscreen method. The growth of Listeria innocua ATCC 33090 and LRGIA 01 strains was not inhibited by LFc and its hydrolysates. Two fractions of dromedary lactoferrin peptic hydrolysate were active against both strains. A tandem mass spectroscopy analysis revealed that the 2 active fractions comprised at least 227 different peptides. Among these peptides, 9 found in the first fraction had at least 50% similarity with 10 known antimicrobial peptides (following sequence alignments with the antimicrobial peptide database from the University of Nebraska Medical Center, Omaha). Whereas 9 of these peptides presented homology with honeybee, frog, or amphibian peptides, the 10th peptide, F152SASCVPCVDGKEYPNLCQLCAGTGENKCACSSQEPYFGY192 (specifically found in 1 separated fraction), exibited 54% homology with a synthetic antibacterial peptide (AP00481) derived from human lactoferrin named kaliocin-1. Similarly, the second fraction contained 1 peptide similar to lactoferrampin B, an antibacterial peptide derived from bovine milk. This result suggests that peptic hydrolysis of LFc releases more active antimicrobial peptides than their protein source and thus provides an opportunity for their potential use to improve food safety by inhibiting undesirable and spoilage bacteria.


Assuntos
Antibacterianos/farmacologia , Camelus , Lactoferrina/farmacologia , Listeria/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Antibacterianos/metabolismo , Bovinos , Feminino , Hidrólise , Lactoferrina/metabolismo , Leite/química , Pepsina A/metabolismo , Fragmentos de Peptídeos , Peptídeos/metabolismo , Peptídeos/farmacologia
9.
J Anim Physiol Anim Nutr (Berl) ; 103(6): 1637-1645, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31389084

RESUMO

The valorization of natural resources in small ruminants feeding can reduce the cost of feed and produce good meat quality. The objective was to evaluate the effects of local feed resources on the physico-chemical aspects, the sensorial characteristics and the fatty acid profile of goat kid's meat. Twenty-six kids are divided in three groups (average body weight = 15.85 kg; age = 4 months). The groups received oat hay (group control C), dried olive leaves + dried Stipa tenacissima (group OL) or grass hay (group Ko). The animals were slaughtered after 90 days of experience, with an approximate final live weight of 18.5 kg. Total solids, pH, fat, crude protein, vitamin, cholesterol and fatty acid contents of meat were determined. The OL group had the highest ultimate pH (6.82 vs. 6.73); cooking loss, gross composition (total solids, protein and fat), cholesterol and colour coordinates (L, a* and b*) were similar among groups. The vitamin E, affected by diet, was higher in group OL than the other groups (3.71 mg/kg vs. 1.32 and 2.17 mg/kg, respectively, for C and Ko groups). Moreover, meat from this group showed the highest saturated fatty acid. Unsaturated fatty acids content was higher in the meat of C and Ko groups. On the other side, polyunsaturated fatty acid level was not affected by the diet treatment. The n6/n3 ratio was significantly affected by the diet; it was lower in meat of groups Ko and OL (3.17 and 3.38 respectively). The feeding effect on sensory quality of meat was not significant.


Assuntos
Ração Animal , Dieta , Carne , Valor Nutritivo , Animais , Fenômenos Fisiológicos da Nutrição Animal , Composição Corporal , Culinária , Clima Desértico , Dieta/veterinária , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Cabras/fisiologia , Carne/análise , Carne/normas , Tunísia
10.
Trop Anim Health Prod ; 48(5): 897-903, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26970973

RESUMO

This study aimed to test the effects of the three management systems on the behavioral repertoire and particularly on the incidence of stereotypical behavior in restrained camels. Five male camels were tested under the following management systems: (i) unexposed, housing in a single box (Unexpo); (ii) continuous exposure, exposed continuously to females (ConExpoF); and (iii) re-unexposed, housing again in a single box (Re-Unexpo). Every day, bulls were filmed for 30 min and videos were analyzed using a focal animal sampling ethogram. Under the ConExpoF system, camels spent the majority of time in standing with opened legs (490.0 ± 94.3 s), looking (925.0 ± 93.7 s), and walking toward the females (206.0 ± 73.4 s) and they ate and ruminated less compared to Unexpo and Re-Unexpo systems. Rumination and standing durations were significantly longer in Re-Unexpo than in Unexpo and ConExpoF management systems. When camels were continuously exposed to females, they showed few stereotypical behaviors compared to Unexpo (490.0 ± 146.1 s) and Re-Unexpo (624.0 ± 146.1 s) systems. The frequency of both total and oral stereotypes was significantly higher in Unexpo and Re-Unexpo systems compared to ConExpoF; however, no significant difference was observed among the three management systems in the frequency of locomotor stereotypes. Overall, it appears that the continuous female exposure system might be a suitable management practice for male camels used for intensive reproduction, as it decreases the manifestation of stereotypical behavior in comparison with housing for 24 h in a single box.


Assuntos
Criação de Animais Domésticos/métodos , Camelus/fisiologia , Restrição Física/veterinária , Comportamento Sexual Animal/fisiologia , Animais , Feminino , Masculino , Reprodução , Estações do Ano
11.
Trop Anim Health Prod ; 48(5): 935-42, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27129886

RESUMO

This study aims to determine the relationship between internal and external udder and teat measurements and evaluate their correlation with milk yield and milk partitioning in the udder of dromedary camels. Six Maghrebi camels reared under intensive conditions were monitored at early, middle, and late lactation. Udder measurements included udder depth, udder horizontal circumference, fore and rear teat length and diameter. Besides, scans of the left fore and rear quarters were taken in duplicate before morning milking (16 h) using an oxytocin receptor blocking agent (Atosiban) to determine teat and gland distension before milk ejection. Cisternal and alveolar milk volumes were then evaluated. Correlation coefficients were calculated between the performed udder external and ultrasonographical measurements and cisternal and daily milk production on the measurement day. Significant effect of lactation stage was observed in all measured traits. All internal and external measurements decreased significantly at late lactation as well as cisternal and total milk yield. The quarter cisternal area averaged 16.3 ± 2.2 cm(2) and decreased about three times at late lactation compared to early and middle lactation. All external and internal measurements were positively and highly correlated (P < 0.001). The knowledge of the relationship between udder internal and external morphological traits would permit to predict udder cisternal storage capacity and can ultimately be adopted to improve milk storage capacity of dromedary camels.


Assuntos
Camelus/anatomia & histologia , Indústria de Laticínios/instrumentação , Glândulas Mamárias Animais/anatomia & histologia , Animais , Indústria de Laticínios/métodos , Feminino , Antagonistas de Hormônios/farmacologia , Lactação/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/fisiologia , Leite , Vasotocina/análogos & derivados , Vasotocina/farmacologia
12.
Trop Anim Health Prod ; 48(2): 387-94, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26644226

RESUMO

The aim of this work was to assess maternal and neonatal changes in plasma proteins, glucose and cortisol and to quantify the colostral immunoglobulin G (IgG) transfer in the peri-partum period in D'man sheep, a prolific breed, taking into account the parity of the ewe. The concentrations of proteins and glucose were high in the ewes on day 7 and at lambing before decreasing. Likewise, cortisol plasma concentration was maximal during the 6 h following lambing and dropped at 12 h. Protein and glucose concentrations were low in lambs at 1 h of birth after which they increased. By contrast, cortisol level was the highest during the first 12 h of birth and then decreased. The colostral IgG level was high at lambing and dropped by over 87 % from 1 to 48 h post-partum. In the newborn, the plasma IgG concentration was lowest at birth and increased rapidly during the first 24 h of birth. Parity influenced maternal physiology with multiparous ewes having the lowest concentrations of proteins, glucose, IgG and cortisol, but the highest colostrum IgG level. Accordingly, lambs born from primiparous ewes had lower protein, glucose and plasma IgG concentrations than lambs born from multiparous ewes. The main outcome of this study was that lambs born from primiparous ewes are characterized by the lowest physiological indices and this may influence their survival chance.


Assuntos
Colostro/imunologia , Imunoglobulina G/análise , Prenhez/fisiologia , Ovinos/fisiologia , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Animais Recém-Nascidos/fisiologia , Feminino , Hidrocortisona/sangue , Imunoglobulina G/sangue , Tamanho da Ninhada de Vivíparos , Masculino , Paridade , Gravidez
13.
Trop Anim Health Prod ; 47(1): 201-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25348647

RESUMO

This work aims to compare the effects of milking at two vacuum levels (38 and 48 kPa) and three pulsation rates (60, 90, and 120 cpm) on milk production and milk flow characteristics. Six multiparous Maghrebi camels in late lactation and once daily milked were used. The best combination of setting for camel's milking was high vacuum and low pulsation rate (48 kPa/60 cpm). Milk yield and average and peak milk flow rate were the highest, while milking time was the shortest using this combination of setting (3.05 ± 0.30 kg, 1.52 ± 0.21 kg/min, 2.52 ± 0.21 kg/min, and 3.32 ± 0.31 min, respectively). Lower vacuum level lengthened milking time by more than 100 % and was not sufficient to extract milk correctly (1.69 to 2.48 times less milk yield harvested), suggesting a negative interaction with the stimulatory effect of pulsation. Higher pulsation rates did not better stimulate the camels and induced more bimodality and lower milk flow rates. Animal characteristics and liner/claw design affect machine milking and further investigations must be carried out to verify their effects and to study long-term effect of high vacuum level on udder health and teat condition.


Assuntos
Camelus , Indústria de Laticínios/métodos , Hidrocortisona/sangue , Ejeção Láctea , Leite/química , Animais , Peso Corporal , Feminino , Lactação , Glândulas Mamárias Animais , Fenótipo , Pressão , Tunísia , Vácuo
14.
Trop Anim Health Prod ; 47(3): 613-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25547806

RESUMO

In many mammalian species, newborns are agammaglobulinemic; thus, colostrum and milk are the main sources of early protective antibodies. These antibodies are produced in the mother's serum and transferred to mammalian glands a few days before parturition. Here, we have studied the transfer of immunity from a she-camel immunized with human serum albumin (HSA) to her calf via colostrum and milk. Our results show that HSA-specific antibodies are produced in the mother's serum and are subsequently transferred to her colostrum. These specific antibodies are then transferred by suckling to the calf. The calf serum did not contain HSA-reactive antibodies at parturition and before the first feed, after suckling, a rise in reactivity was observed peaking at 24 h postpartum. The involvement of heavy chain antibodies (HCAbs) in the process of immunity transfer was also examined, and it was found that they were also transferred from the colostrum to the calf serum like conventional antibodies.


Assuntos
Camelus/imunologia , Colostro/imunologia , Imunidade Materno-Adquirida , Prenhez , Animais , Animais Lactentes/imunologia , Anticorpos/sangue , Feminino , Imunoglobulina G/sangue , Cadeias Pesadas de Imunoglobulinas/sangue , Gravidez
15.
J Dairy Res ; 81(4): 494-503, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25234858

RESUMO

We studied the effects of changes in the milking routine (lack or presence of 30-s prestimulation, 0 or 1, 2 or 4-min delay between preparation and cluster attachment) and environmental perturbation (unusual loud sounds capable of frightening animals just after stall entry or during the course of milking) on milk removal and milking-related behaviour in dairy dromedary camels. A 30-s prestimulation decreased incidence of bimodal milk flow curves and increased occurrence of the best milk ejection patterns with higher milk flow but had limited effect on milk production in our well-trained animals within a good machine milking setting. However, unusual sounds heard from the beginning of milking or even after milk ejection caused inhibition or disruption of milk removal and modification of camels' behaviour. Milk ejection was significantly delayed (1·58±0·17 min), residual milk increased over 40% of total milk yield and average and peak milk flow rates were significantly lowered when unusual noises were heard from the beginning of milking. These environmental perturbations increased signs of vigilance and the number of attempts to escape the milking parlour. Delaying cluster attachment for over 1 min after the end of udder preparation caused serious milk losses. Up to 62% of total milk was withheld in the udder when the delay reached 4 min. Average and peak milk flow rates also decreased significantly with delayed milking. Signs of vigilance and attempts to escape from the milking parlour appeared when camels waited for over 2 min. After a 4-min delay, camels showed signs of acute stress. Defaecation prior to milk ejection (solid faeces) and rumination during milking can be used to assess camels' milk ejection during milking. Animal welfare and milking efficiency can be ensured when camels are pre-stimulated, milked in calm conditions and with cluster attachment within a maximum of a 1-min delay after stimulation.


Assuntos
Criação de Animais Domésticos/métodos , Camelus/fisiologia , Lactação/fisiologia , Animais , Feminino , Estresse Fisiológico , Fatores de Tempo , Tunísia
16.
J Dairy Res ; 81(2): 173-82, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24622212

RESUMO

In order to evaluate milking ability in dromedary camels, 124 milk flow curves were registered during morning milking of 20 dairy Maghrebi dromedary camels. Animals were in lactations 1-8, were 6-19 years old and were 4-15 months of their current lactation. Milk flow curves were recorded using an electronic milk flow meter (Lactocorder®). Milk flow curves were classified in three typical patterns: type 1 represents curves with one high and short peak of milk flow; type 2 represents curves with a moderate mean milk flow rate during a large plateau phase; and type 3 represents curves with lower mean milk flow rate and a relatively longer milking duration. The ratio of the different milk flow patterns in the population evaluated was 40:38:22% for types 1, 2 and 3, respectively. The highest milk yield per milking, average and peak milk flow were observed in camels with type 1 curves (4·24 kg, 1·49 and 3·54 kg/min, respectively) followed by type 2 animals (3·30 kg, 1·12 and 2·12 kg/min, respectively) and lastly type 3 curves (2·34 kg, 0·65 and 1·23 kg/min, respectively). This study confirmed that a major proportion of dromedary camels have a suitable machine milking ability. Nevertheless, our results suggest that pre-stimulation and improving the milking process may improve milking efficiency and guarantee a more complete and rapid emptying of the udder.


Assuntos
Camelus/fisiologia , Indústria de Laticínios/métodos , Lactação/fisiologia , Leite/fisiologia , Animais , Indústria de Laticínios/instrumentação , Feminino , Hidrocortisona/sangue , Cinética , Ejeção Láctea/fisiologia , Tunísia
17.
Trop Anim Health Prod ; 46(5): 861-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24659302

RESUMO

Camel management has been changing in recent years from an extensive to a semi-intensive or intensive system, particularly for breeding bulls and dairy dromedary camels. Captivity may affect animal welfare, and low libido is the major complaint for housed breeding bulls. Since welfare status could also affect reproductive performance, the aim of this study was to evaluate different management practices on behavior, particularly on sexual behavior, and to identify some behavioral needs of male dromedary camels reared for semen collection. The effects of the following management systems on their behavior were compared: (i) traditional: housing in a single stall for 24 h (H24), (ii) housing in a single stall for 23 h with 1 h free in the paddock (H23), and (iii) housing in a single stall for 22 h and 30 min with 1 h paddock time and 30 min exposure to a female camel herd (ExF). During the trial, blood cortisol concentrations were assessed and camels were filmed daily for 30 min in the mornings and during a female passage in the evenings. Videos were analyzed in order to fill out a focal sampling ethogram and to score sexual behavior. As a result, there were no differences between the H24 and H23 systems, whereas ExF had a significant positive impact on their sexual behavior score and behavioral repertoire, further reducing cortisol levels. Overall, it seems that male dromedary camel welfare status improves when their behavioral needs for social interaction and movement are satisfied.


Assuntos
Criação de Animais Domésticos/métodos , Camelus/fisiologia , Comportamento Sexual Animal/fisiologia , Animais , Feminino , Masculino , Reprodução
18.
Trop Anim Health Prod ; 46(2): 313-21, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24122649

RESUMO

Camels are seasonal breeders, and their sexual behavior is influenced by environmental conditions, but the relationship between climatic factors and sexual behavior has been poorly described in the available literature. Nowadays, the male camel living habit is shifting towards captivity; thus, this study was carried out to evaluate the sexual behavior of housed male dromedary camel through female's parades and to correlate it with climatic parameters. Four housed sires, reared for semen collection, and one dam were used and the trial lasted 8 weeks, considering the first week as control. Six days per week and during evenings, the female was brought near each males' boxes, while two observers filled a behavioral sampling ethogram and scored the male sexual behavior. After this parade, blood samples were taken from the female to evaluate the estradiol concentration. In addition, the following meteorological parameters were recorded, everyday, at 9:00 a.m. and 19:00 p.m.: pressure, wind, temperature, humidity, and H-index. The correlation between sexual behavioral score and female estradiol concentration and climate parameters was analyzed. All the behavioral parameters showed a significant upward trend; female estradiol concentration varied during the period and picked at week 5. Male sexual behavior was negatively correlated with morning H-index, wind, and temperature, and positively correlated with pressure and evening humidity, whereas it was not correlated with estrogen. In conclusion, female parade was a successful method to evaluate and stimulate the occurrence of housed male dromedary camel sexual activity that resulted to be negatively affected by hot temperature, warm wind, and lack of rain.


Assuntos
Meio Ambiente , Comportamento Sexual Animal/fisiologia , Animais , Camelus/sangue , Feminino , Abrigo para Animais , Umidade , Masculino , Temperatura
19.
Animals (Basel) ; 14(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38791692

RESUMO

Examining the distribution patterns and spatiotemporal niche overlap of sympatric species is crucial for understanding core concepts in community ecology and for the effective management of multi-species habitats within shared landscapes. Using data from 26 camera-traps, recorded over two years (December 2020-November 2022), in Sidi Toui National Park (STNP), Tunisia, we investigate habitat use and activity patterns of the scimitar-horned oryx (n = 1865 captures) and dorcas gazelle (n = 1208 captures). Using information theory and multi-model inference methods, along with the Pianka index, we evaluated the habitat characteristics influencing species distribution and their spatial niche overlap. To delineate daily activity patterns, we applied kernel density estimation. Our findings indicate minimal spatial overlap and distinct environmental factors determining suitable habitats for each species. Furthermore, we found significant temporal niche overlaps, indicative of synchrony in daily activity patterns, with both species showing peak activity at dawn and dusk. Our results indicated that oryx and gazelle differ in at least one dimension of their ecological niche at the current density levels, which contributes to their long-term and stable coexistence in STNP.

20.
Proteomics ; 13(7): 1180-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23349047

RESUMO

Camel milk has been widely characterized with regards to casein and whey proteins. However, in camelids, almost nothing is known about the milk fat globule membrane (MFGM), the membrane surrounding fat globules in milk. The purpose of this study was thus to identify MFGM proteins from Camelus dromedarius milk. Major MFGM proteins (namely, fatty acid synthase, xanthine oxidase, butyrophilin, lactadherin, and adipophilin) already evidenced in cow milk were identified in camel milk using MS. In addition, a 1D-LC-MS/MS approach led us to identify 322 functional groups of proteins associated with the camel MFGM. Dromedary MFGM proteins were then classified into functional categories using DAVID (the Database for Annotation, Visualization, and Integrated Discovery) bioinformatics resources. More than 50% of MFGM proteins from camel milk were found to be integral membrane proteins (mostly belonging to the plasma membrane), or proteins associated to the membrane. Enriched GO terms associated with MFGM proteins from camel milk were protein transport (p-value = 1.73 × 10(-14)), translation (p-value = 1.08 × 10(-11)), lipid biosynthetic process (p-value = 6.72 × 10(-10)), hexose metabolic process (p-value = 1.89 × 10(-04)), and actin cytoskeleton organization (p-value = 2.72 × 10(-04)). These findings will help to contribute to a better characterization of camel milk. Identified MFGM proteins from camel milk may also provide new insight into lipid droplet formation in the mammary epithelial cell.


Assuntos
Camelus/metabolismo , Glicolipídeos/metabolismo , Glicoproteínas/metabolismo , Proteínas de Membrana/metabolismo , Proteômica/métodos , Animais , Compartimento Celular , Eletroforese em Gel de Poliacrilamida , Gotículas Lipídicas , Membranas , Anotação de Sequência Molecular
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