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  • با سلام

از نوشتار شما بسیار لذت بردم. سوالی را مطرح میکنم: آیا تولید کشمیر در ایران مقرون بسرفه تر از خرگوش آنقوره است؟ یا برعکس
نویسنده:
م.انصاری

   با عنایت به سابقه پرورش بزهای تولید کننده کشمیر در ایران و سازگاری اقلیمی، تولید کشمیر در مقایسه با آنقوره مقرون بصرفه  تر بنظر می رسد. تولید آنقوره در ایران نیاز به بررسی دقیق موضوع از نظر توجیه اقتصادی دارد.

 

 

 

 

 
  • با سلام چند وقتی است که به پرورش خرگوش آنقوره علاقه مند شده ام آیا میتوانم اطلاعات بیشتری از شما در این مورد کسب کنم
        با تشکر
نویسنده:
امید

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 جناب آقای رأفت با سلام و احترام درخصوص پرورش خرگوش آنقوره سوالاتی داشتم. از آنجا که درباره پرورش این گونه، در محافل، خصوصا کارآفرینی، بحث میشود به گونه ای که پرورش آن را بسیار راحت و پرسود جلوه می دهند،استدعا دارم در باره پرورش آن منابع علمی به بنده معرفی نموده و نیز درباره بازار آن درایران و خارج از ایران منابع اطلاعاتی موثق را به انیجانب معرفی نمایید.  با تشکر فراوان محبی

جواب:

باید ببینید افرادی که پرورش خرگوش آنقوره را توصیه می کنند چقدر تجربه در این مورد دارند؟ آیا تاکنون فارم آنقوره را دیده اند؟

 

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برای اطلاعات بیشتر درمورد پرورش خرگوش آنقوره به ادامه مطلب یا کتاب مراجعه نمایید.

 


Angora

Angora, the hair of Angora rabbits, is one of the five keratinic textile fibres of animal origin of significant economic value. Wool from sheep is of course by far the main fibre, at over 1.3 million tonnes per year (thoroughly washed). The four others: mohair, angora, cashmere and alpaca, each at outputs of 5 000 to 30 000 tonnes, exhibit original qualities of fineness, lustre and feel for the production of high value added luxury items. Angora is often considered one of the "noble" fibres.

Angora: Characteristics

Textile properties

In the matter of textiles, "angora" without any other qualification refers solely to the hair produced by Angora rabbits.

Its International Organization for Standardization (ISO) symbol is WA: W for wool, reserved for noble textile hair, as opposed to H used for ordinary hair. The letter A is for the Angora rabbit and distinguishes it from the mohair produced by the Angora goat, M. The symbol for mohair is thus WM. The short hair of the ordinary rabbit is designated HK (K = Kaninchen which is "rabbit" in German).

Length. Angora hair is unusually long owing to the prolongation of the active phase of the hair follicle cycle: the hair grows for approximately 14 weeks, whereas that of the rabbit with ordinary (short) hair grows at the same rate but for only five weeks. This is due to the presence of a recessive gene in Angora rabbits.

Apart from this great length, there is no other modification either in the hair's structure or in the composition of the coat, which contains the three classic types of rabbit hair.

·guide hairs: the longest (10 to 11 cm) and the roughest; they cover and guide the coat;

· guard hairs ("barbes"): shorter than guide hairs (8 cm); their rough points lie on the coat and hermetically seal it (covering hair); four to each guide hair;

· down: shortest hair (6 cm); rounded point, hardly visible, very fine body (14 m). Very numerous, 60 to a guide hair, they constitute the thermic isolation undercoat. The length of angora hair accounts for its textile value, because it permits cohesion in the thread.

Friction coefficient. The rabbit's hair has a characteristically low friction coefficient owing to the very slight relief of the cuticle scales. This results in a particular softness to the touch, but also an exceptional capacity for slipping. This is why the length of angora is important; the hair is twisted and stays in the thread. The use of ordinary rabbit hair to replace angora produces threads of bad quality which spread everywhere: this is a fraudulent process which reflects badly on the Angora industry.

Because of its softness angora hair is used for the manufacture of insulating underclothes (keratin). Ten percent angora in a mixture of wool, cotton and synthetic fibres makes an extremely soft fabric, very easy on the skin.

The kemp points and the covering hairs, which are more rigid, rise from the fabric, giving it a fluffy appearance which is much prized. Whole angora hairs obtained by depilation are the most suited for this purpose.

Other characteristics of angora hair

Although the Angora rabbit exists in all colours, only the albino strain is produced now. Its coat is entirely white, which is an advantage for dyeing. Coloured Angora rabbits are raised in India for the manufacture (by breeders themselves) of undyed artisanal fabric with muted colour motifs. The hairs are all medulated (hollow), which makes them lighter than wool (density 1.1 against 1.3) and increases their insulating properties. They have all the properties of keratin, notably insulation, water absorption and good dyeing quality.

Mini-glossary

Selected technical terms for fur production

Curing: tanning skins with hair.

Shearing: separating the hair from the skin in which it is implanted.

Knife marks: perforation or slit from skinner's knife.

Skinning: separating the skin (with hair) from the animal (carcass).

Brushing: gently brushing hair back into place at various stages in the curing process.

Pellicle: a thin collagenous film on the flesh side. The subskin muscle is removed with the dermis during skinning.

Fur: rabbit skin and hair.

Glossing: dyeing the hair of cured pelts.

Moulting: period of reactivation of hair follicle. The base of the former hair is hydrolized, freeing the hair canal for the emergence of the new hair.

Moulting zone: section of skin where hair follicles were active at slaughter. Seen as dark blue patches on the skin side of the pelt. The hair comes out easily or is still very short, its growth interrupted by slaughter.

The Angora rabbit's coat is 98.5 percent pure as cutaneous secretions (restricted to those of the sebaceous glands) are very slight and the animal grooms itself frequently (a sheep's fleece is only 50 percent pure because of the presence of suint). Angora wool goes straight to the card without previous washing: it is imperative that the producer keep constant control over the cleanliness of the animals.

Commercial qualities

There are several grades of hair, identified by length, type of animal and cleanliness. First-quality hair which represents 70 percent of the coat must be over 6 cm in length (down) and clean. This grade was worth 950 FF a kg in 1984, but only 300 FF in 1981 to 1982. Since 1988, the price has ranged from 300 to 380 FF.

Second-quality hair is clean but too short (down less than 6 cm) or too woolly. It is grown on the belly and extremities and is worth about 20 percent less than the first-quality wool. The hair of the young Angora rabbit is shorter and softer. It is the product of the first and sometimes the second collection. The clean but felted hairs collected on the necks of females or breeding animals are worth only 15 percent of the value of first-quality hair.

Dirty hair of any length is virtually worthless. At best, it is worth less than shorn hair from ordinary rabbit breeds. Its value would be no more than 5 or 6 percent of the first quality. Clean hair is therefore absolutely essential in angora wool production.

Raising Angora rabbits

Angora rabbits are reared primarily for their hair. The production of this hair calls for an entirely different set of techniques from those used in meat-rabbit production. These techniques have historically reached the pinnacle of specialization in France, where the sole target has long been wool production, but some countries, headed by China, are now also developing this specialization.

Sexual balance. The adult female produces the hair: adult, because top-quality angora is only produced from the third collection at nine months, and female because the female produces more hair than the male - an average of 1 kg against 700 to 800 g for the male. Therefore the hair-producing stock is made up of adult females that are maintained as long as possible, with reproduction kept at a minimum. Gestation and especially lactation reduce hair production by one-third.

The number of breeding bucks is kept to a minimum. The proportion is only 2 or 3 percent in hair-production units. In France the males not destined for breeding are culled at birth, which hastens the development of the female young.

Harvesting schedule. The hair is collected every 90 to 100 days, when the follicles reach the resting stage and before hair starts falling, which would cause felting and reduce the value. The hair is cut with scissors or electric or manual shears, or collected by depilation. Depilation has long been the technique of choice in France, synchronizing the reactivation of hair follicles with a well-structured coat with good guide hairs. Since the 1980s French breeders have been using a depilatory fodder sold under the name LagodendronR (Société Proval, 27 rue de la gare de Reuilly, 75012 Paris). With careful use of this product, rabbits can be shaved more quickly and easily and less stressfully. Scissors is the more common technique in China, with shearing more common in Central Europe and South America. French-type Angora rabbit hair is better collected by depilation, whereas shearing or scissors are better for Chinese or German-type Angoras. The differences between their genotypes include, inter alia, the simultaneous resumption of hair follicle growth in accordance with the collection method.

Angora hair must be sorted into the different grades at collection, which is the best time. A skilled operator takes about half an hour: less than 20 minutes and more than 45 minutes are both very rare.

FIGURE 50 Comparative growth of hair types in Angora and common rabbits

Habitat

Angora rabbits must be reared in single cages, at least after the age of two months when the hair is first collected. The cage must be big enough (about 0.5 m2) and high enough (about 0.5 m). Wire-mesh floors are rarely recommended. Angora rabbits, particularly French ones, have very fragile paws for their weight of roughly 4 kg. As they are to be kept for several years it is better not to take chances.

French breeders have opted for cement hutches and straw litter, for clean hair and paw protection. The straw absorbs the urine. A little fresh straw is added each week and the entire litter changed every four or five weeks. Duckboard has been a frequent choice in other countries, with the slats made of bamboo (as in China) or plastic. Some breeders, for example in India, use German-type Angoras and have successfully raised them on wire-mesh floors as for meat-rabbit production (see Chapter 6).

Angoras do not like high temperatures (over 30°C). Low temperatures are a problem as well (below 10°C), but only during the days following hair collection. It is therefore not necessary to heat all production buildings (in fact open-air production has long been the practice in France); on the other hand, the denuded rabbit must be protected, particularly where depilation is the collection technique. Breeders use several methods: two-stage depilation at intervals of a few days, leaving a "back" which is subsequently removed; body-coat, warmers, post-depilation boxes, etc.

Feeding and hygiene

Feeding Angora rabbits involves several peculiarities compared with meat rabbits. Indeed, the Angora at peak production is an adult rabbit in a situation of maintenance from the physiological standpoint. Its growth is complete and reproduction is limited to a few animals. It must, however, produce over 2 kg of dry proteins a year -more than 1 kg of keratin (hair) and the same amount from the internal sheath of the hair follicle. This is the equivalent of 7 or 8 kg of muscle.

This explains the need for a high-protein diet - 17 percent. The keratin in the hair is rich in sulphur amino acids, exporting 35 g of sulphur a year, so the proper intake of these amino acids (0.8 percent in the ration) must be ensured. The high productivity of modern Angora strains (up to 1 400 g per year), make full productivity difficult under traditional feeds such as hay, alfalfa, oats, barley, etc. The amounts would be excessive and deficits in sulphur amino acids inevitable. For cost considerations (excluding labour costs) some French breeders still combine these feeds with balanced concentrates containing methionine, vitamin and mineral supplements. Almost all breeders use only pelleted feeds for Angoras which are easy to administer. In this case an average 170 to 180 g should be fed to each rabbit daily.

The Angora rabbit's feed requirements follow the cycle of collection (every three months) and hair regrowth. Requirements increase after depilation as the animal is then hairless and energy losses by radiation are very great. By the second month the animal is again well covered, but this is when the hair grows fastest so the ration must of course remain adequate. In the third month, requirements decrease because the hair grows more slowly and, as collection time approaches, starts to fall. Daily rations need to be adjusted carefully to these variable requirements.

It is now the practice to give 190 to 210 g per day of dry matter during the first month, 170 to 180 g during the second month and 140 to 150 g during the third month. This is less imperative when the wool is sheared. It is also recommended that the rabbits not be fed one day a week so the stomach can empty, preventing or at least diminishing the risk of the hair balls that can form from self-grooming (very hard balls called trichobezoars that obstruct the pylorus and usually end in death).

Most losses of adult Angoras occur during the days following hair collection as the animals then have problems maintaining thermal balance. They become particularly sensitive to respiratory germs (pasteurella, coryza, etc.). The breeder must therefore be constantly on the alert regarding their general hygiene (frequent litter renewal, cleaning, disinfecting). Having to replace working females with young does lowers average production levels because first-year Angora output is appreciably lower: 650 g compared with 1 kg. The usual yearly rate of renewal is 25 to 35 percent.

Labour

Labour in Angora rabbit production may be subdivided into five categories:

· feeding;
· hair collection;
· cleaning and disinfection of the buildings;
· curative or preventive health care (vaccinations);
· reproduction.

Feeding is not labour-intensive provided the breeder distributes only balanced pelleted feeds in easily accessible feeders. In this case 40 minutes per day and 210 hours per year would be needed for a production unit of 400 Angora rabbits. The time is doubled for coarse feed such as hay and cereals. A daily distribution of straw or roughage, including fasting days, transport and sifting of feed must be reckoned in, raising the time spent on feeding to 400 hours per year.

Hair collection is the most time-consuming operation. The calculation needs to include not only the actual hair removal by shearing, cutting or depilation but also moving the rabbit from its hutch to the collecting table, the grooming phase to remove filth or plant matter from the coat, weighing different grades of hair, keeping records, returning the rabbit to the hutch, plus postharvest thermal stress reduction measures. All in all, some 1 000 hours per year are required for a 400-rabbit production unit.

Complete litter removal (cleaning) for hutches or cleaning out wire-mesh cages, disinfection procedures and sweeping takes at least 250 hours per year.

Veterinary care is basically preventive: vaccinations and general disease prevention can take up to 175 hours per year.

Reproduction-related work (handling breeding animals, checking gestation and kindling, sexing newborn rabbits, weaning) also requires 175 hours per year.

In all, a production unit of 400 Angora rabbits requires 2 000 working hours per year under rational production conditions.

Sources of variation in angora hair production

Genetic estimates of different strains

Although there are several strains of Angora rabbit, only the German, French and Chinese (Tanghang, Wan, etc.) strains are of economic interest at this time. The Chinese strains (including the German strain reared in China and South America) supply over 95 percent of the angora hair sold in the world. The European, French and German strains deserve mention for their specific features and because they have been selected for over 50 years.

Weight production. Hair-weight production has long been the sole focus in Angora rabbit selection. These genetic improvement efforts in France and Germany have produced highly similar acceleration of hair growth.

The annual output of does at the INRA experimental production unit in France rose from 885 g/year in 1980 to 1 086 g/year in 1986, a phenotypical gain of 31 g/year. Animals tested at the Neu-Ulrichstein Hesse Centre in Germany gained in productivity from 400 g/year in 1945 to 1 350 g/year in 1986: a phenotypical gain of 32 g/year. Production in the French and German commercial sectors lagged slightly behind these figures with an estimated annual production per doe of 1000 g/year under French and 1200 g/year under German production conditions.

There are major gaps in China by province and by production systems. The figures range from 261 g/year (unspecified Chinese strain, 1985) to 815 g/year (Wan strain, 1992) for does. Production conditions, particularly feeding, are highly influential because German rabbits under Chinese conditions are, according to the literature, producing from 422 to 820 g/year.

Non-genetic factors in quantitative hair output

Most of these factors are known today. The most important, judging by weight at each collection, is of course the interval between two collections. This effect is attenuated when considering annual output.

The collection technique (shearing or depilation) is an important factor, particularly for the (depilated) French strain, as shearing reduces adult doe productivity by about 30 percent.

The number of the hair collection is important up to the fifth collection for French strains: the first four collections successively represent 11 percent, 60 percent, 81 percent and 93 percent of adult production. The German strain is apparently more precocious, with several references citing the fourth and even the third collection as representing full potential productivity.

The sex factor is very marked in the French strain: male rabbits produce 20 percent less hair. This is not so true of the German strain, where the literature reports a difference of zero to 15 percent, with most citing a figure of 10 percent less for male rabbits. Live weight is fairly irrelevant, except during the growth period, but should be correlated with the collection number (first, second, etc.).

The seasonal factor should also be taken into account: winter collection is always heavier than summer collection, varying by 4 to 30 percent depending on the author. It does seem that the higher the productivity of the strain, the weaker the seasonal effect.

Other variation factors such as the season of birth have been studied, but new data are needed to confirm these findings. Undeniably, other factors such as diet (deficiencies), temperature and comfort do have a direct influence on quantitative productivity of hair.

Non-genetic variation factors in qualitative hair production

Angora hair quality parameters are length, the fineness of the down, guard-hair diameter and fur structure and composition. Concerning this last point, the basic distinction is between woolly fur and fur thick in guard hairs. The latter, in accordance with the proposed classification presented to the 1992 Corvallis Convention, include those in which over 70 percent of the guard hairs are full (i.e. with pointed ends) and where less than 1 percent of the fibre is shorter than 15 mm. The other furs are considered woolly. Felting or dirty fur is also considered a quality parameter.

The interval between hair collections is a decisive factor in hair length.

In the distinction between guard hair - obtained by depilation and woolly hair obtained by shearing, the collection procedure is fundamental.

The number of the collection is important (at least at the first harvest) for all rabbit strains and for the second and third collections in French strains, where the young rabbits still produce woolly fur, even after depilation.

The sex factor is less of a distinction and is weaker in the German than in the French strain but males do show a more marked tendency towards felting.

Live weight and season have less effect in adults; at most there is a structural difference: the length ratio of underfur to guard hair is less in summer than winter: 55 percent in summer as opposed to 65 percent in winter.

Prospects for angora wool production

A point to be considered very carefully is that Angora rabbit production is labour-intensive and also requires great expertise. The slightest mistake can mean the loss of productive adults: the animals have to be over a year old to return a profit. Hair collection is always a delicate operation and careless sorting irredeemably downgrades the product. Above all, not all climates are suitable: excessive heat and intense light (albinos) are very bad elements. In cold countries, or in countries with cold winters, the solution is to use buildings that shelter the animals against the rigours of the winter. Recently denuded animals require special care, however. The feed requirements of Angora rabbits are important: a poor, deficient diet will always mean qualitatively and quantitatively poor hair production.

Last and probably most important, the price of angora wool fluctuates: first, according to fashion, with a cycle of three to five years, but also and more abruptly, in classical supply and demand terms, when world production is structurally either excessive or insufficient compared with average utilization of the fibre. The price of angora (sheared wool) suddenly doubled between 1976 and 1978 (from US$13 to $28 per kilogram) because world production, estimated at 900 tonnes in 1977, was clearly insufficient. The price remained at this high level for about ten years, following the dollar; up to US$45 to $50/kg, and then in 1988, when world production had increased by a factor of ten to 9 000 tonnes, the market collapsed and the price had fallen to US$20/kg by the summer of 1991. There was a recent reversal of this slump in Chile, Argentina, Hungary and France (and China to a lesser extent), bringing the price up to US$30 in 1992. The volumes traded, and hence angora utilization, continue to rise: the production figure is likely to reach 10 000 tonnes per year again.

As for France, the only developed country to have maintained an angora output of original quality (the guard hair), the situation is one of unprecedented crisis. Production costs no longer permit the sale of French angora wool at less than US$75/kg and the gap between that and the world price appears immense to foreign buyers (the difference between world prices and the price for French angora conventionally being 40 to 50 percent). Quality French angora hair has remained virtually unexported since 1988, therefore, and is very difficult to market internally, either in the unprocessed form for manufacture or in manufactured form (e.g. sweaters).

Clearly this is a highly speculative production and should be approached with great caution. The utilization of the noble textile fibre, angora, continues to grow despite competition from other natural fibres and particularly from synthetic fibres. This is partly due to the new sectors that have opened, particularly for fabric, in combination with cashmere and silk. The price slump from 1987 to 1991 did indeed follow ten very favourable years, after decades of good angora prices. Better times could return again

  
نویسنده : رأفت ; ساعت ۱۱:٢۳ ‎ق.ظ روز ٧ شهریور ۱۳۸٧