Management to Increase Herd Performance

Increasing the production of a herd rests on 3 main aspects: 1) improvement and monitoring of reproductive performance, 2) adequate nutritional management, 3) prevention of diseases

Reproductive management

The backbone of any reproductive management program is the definition of breeding objectives, the maintenance of good breeding health records, management of breeding activity, and regular reproductive evaluation of the breeding stock.

Defining breeding methods and objectives

Breeding methods and objectives should be defined for each group of animals before joining. This should include:

*    Identifying animals to be bred

*    Defining the type of breeding management to be used (hand mating, free joining, etc.)

*    Planning for the booking of different studs

*    Deciding the length of the breeding season (continuous or seasonal)

*    Targeting breeding dates for young and postpartum animals

*    Scheduling of regular veterinary herd visits

Record keeping

Methods for animal identification have been described in earlier chapters and range from tattoos to electronic identification. All reproductive and health events should be recorded with precision and used for periodic herd evaluation. Computer record-keeping programs for llama and alpaca herds are available on the market but have not yet reached the state of advanced development seen in software designed for the management of cattle.

Management of breeding

Two main systems are used in camelidae breeding: hand mating, and pen or free mating. There is very little use of artificial breeding. The selection of the type of breeding system depends on many factors.

Hand mating

In hand breeding, the female is led to the male (or vice versa) and the mating is supervised. This is by far the most common breeding system used in intensively managed animals such as racing dromedaries and some prized herds of llamas and alpacas. This system has several advantages, including a better management of the stud, prevention of accidents, and acquisition of precise breeding records. In addition it allows close supervision of individual animals. The major drawback of this system is the risk of breeding females that are not ready. In the dromedary, we have noticed that males trained for hand breeding tend to breed any female that is submissive without regard to her follicular activity. Also, trained females will easily assume the copulation position without necessarily being at the right follicular stage.

Hand mating can be optimized with regular veterinary examinations, especially when dealing with very valuable animals. The females should be examined by ultrasonography every 2 or 3 days and only those presenting a mature follicle and increased uterine tone should be bred. This system allows us to achieve an 86% first-service conception rate in the normal dromedary female.

Special care should be taken to insure that the breeding area has good footing and is comfortable for the animals when they assume the copulation position. In the dromedary, the best surface is sand. The perineal area and tail of the female should always be checked for signs of vaginal discharge before breeding. The female should be prepared by washing the perineal area, especially if a gynecological examination is done prior to breeding. In llamas, the female's tail should be wrapped to avoid formation of hair rings on the male's penis. In the dromedary, the penis should be manually guided to prevent rectal intromission.

There are no studies on the optimal frequency of utilization of the male in this system. In the dromedary, we have observed a frequency of use varying from 2 to 15 matings per day. We have been using males 4 times daily with one day of rest per week without any effect on fertility. It is certain that more studies are needed for the determination of the optimal use of studs in these species according to their age, fertility, and testicular size (sperm production).

It is a common belief that the dromedary camel will not breed in the presence of people but this is not true. However, to prevent distraction, the breeding area should be calm and movement of other males or females restricted because many males tend to behave defensively and stop breeding, especially when they see other studs. Breeding should be conducted during the early hours of the day or late afternoon in hot climates. In the llama, when breeding is conducted indoors, it is important to provide enough ventilation (using a large fan or just natural air circulation) to prevent heat stress during the time of breeding which may take up to 50 minutes.

When breeding is supervised, it is important to record some specific observations on the breeding. We note the following information:

1)    Behavior of the female: readily accepts the male, difficult, or indifferent

2)    Male behavior: readily accepts the female, attempts to bite

3)    Timing of copulation: time from introduction of the female to mounting and duration of copulation

4)    Quality of thrusting: good, powerful, weak, number per minute

These observations help the breeder to judge if ejaculation has taken place. However, the only certain method for evaluation of the occurrence of ejaculation is through vaginal examination of the female following breeding.

Pen, group or paddock mating

Group mating is practiced in many herds. Its biggest advantage is that it is less labor-intensive than hand mating. The male can be permanently left with the female, or introduced only at specific times of the day. In traditional management of dromedaries, males are introduced only at night. However, the breeding records are often not precise and are limited to the dates of the beginning and end of the joining period. Therefore, prediction of the date of parturition can not be made in this system unless pregnancy examinations are done at regular intervals during the joining period. In the dromedary, this is easily accomplished by teasing every 14 days and removing all females that show the characteristic pregnancy behavior from the herd (cf. Examination of the female). Confirmation of pregnancy in these females is done by ultrasonography or rectal palpation. We are currently investigating the efficiency of Kamar bovine heat detection patches as a method for the identification of mated or mounted dromedary females.

There are no studies on the optimal male-to-female ratio to be used in the free breeding system. In the dromedary, we have observed ratios ranging from 1:25 to 1:300 (male : female).

Artificial breeding

The use of artificial insemination and embryo transfer is still very limited in camelidae. The management of animals when using these techniques has been described in detail in another chapter in this publication (cf. Artificial breeding).

Reproductive examinations

Regular reproductive examination is the key for the success of any reproductive management program. Types of examinations to be conducted and their schedule depend on the category of animals examined. In a breeding project, animals will fall into one of the following categories according to their breeding status:

1)    Breeding males fall into two sub-categories: confirmed studs that have bred successfully for at least one season, and new, recently-purchased or young males

2)    New females. This group includes all young, recently-purchased females or visiting females with no reproductive history

3)    Barren females: females that failed to conceive or lost their pregnancy during the preceding season

4)    Pregnant females that are due to give birth during the season and be rebred

During the breeding season, reproductive examinations of these categories of animals will fall into one of the following types:

*    Pre-breeding examination

*    Pregnancy diagnosis

*    Examination for reproductive problems

*    Examination of the peri-parturient female

Pre-breeding examination

A pre-breeding examination should be done on all animals in the first 3 breeding-status categories. The extent of the examination will depend on the animal. Examination of the confirmed studs can be limited to evaluation of the external genitalia, particularly the size and consistency of the testis. However, a more detailed examination, including an attempt to collect semen or test breed, should be done on males with no reproductive history. At the moment, the best methods to test male camelids are to collect semen after breeding, test breed a group of females, or to breed superovulated females and collect embryos.

All females should be examined (rectal palpation, ultrasonography and vaginal examination) at least once before joining to ensure that they have a normal genital tract. Barren females should be examined thoroughly to determine the reason of reproductive failure (cf. Female examination).

Pregnancy diagnosis

Early pregnancy diagnosis is a critical aspect of reproductive management of camelidae. It saves valuable time and resources by identifying females or males with reproductive problems. The earliest pregnancy diagnosis can be achieved by observation of the female behavior or by measuring plasma progesterone levels. Pregnancy status is confirmed by ultrasonography at a later date.

Pregnancy diagnosis based on female behavior is possible from 14 days post-breeding. The pregnant llama refuses the male by "spitting off," whereas the pregnant dromedary female shows the characteristic posture with tail curling (cf. Physiology). These methods of pregnancy diagnosis are not 100% accurate and should be combined with ultrasonography and progesterone assay.

Progesterone plasma level rises following mating and is maintained above 2 ng/ml during the entire pregnancy, while in the non-pregnant female this level falls sharply after 12 days post-coitus. Progesterone levels in blood or milk of the bred female can be determined by simple techniques (RIA - ELISA).

Rectal ultrasonography can be used with high accuracy starting at day 18 post breeding in the llama and dromedary (cf. Female examination). For alpacas and small llamas, pregnancy diagnosis can be done by abdominal ultrasonography at 60 days of pregnancy (cf. Female Examination).

It is important to remember that embryonic loss can range from 5% to 30%. Most of these embryonic deaths occur before day 60 of pregnancy. Therefore, an examination for the confirmation of the pregnancy should be scheduled at 60 days. A third pregnancy examination is preferably done at 120 days. All females should be rechecked at the estimated last trimester of pregnancy when an adjustment of nutrition is required.

Examination for reproductive problems

Early detection of reproductive problems and their treatment saves a lot of time and allows a more efficient use of the male. All females that fail to become pregnant or are not observed mating after 2 weeks of joining should be examined for reproductive problems according to the protocol presented earlier in this publication (cf. Breeding soundness of the female). Detailed gynecological examination should also be performed as soon as possible on animals that have experienced abortion or early embryonic loss.

Examination of the peri-parturient female

Pregnant females that are near term (calculated on the basis of mating date and average pregnancy length) should be regularly inspected for signs of approach of parturition. This can be done by the owners if they have good experience in camelidae breeding. Any female that fails to show evident signs of pregnancy by the last trimester of gestation should be examined by the veterinarian. Examination of the peri-parturient female also includes postpartum examination in order to decide on the time of the next breeding (cf. Management of parturition and postpartum breeding).

Management of parturition and neonatal care

One of the most important aspects of reproductive management is the care of the peri-parturient female and the newborn. Improvement of the chances of survival of the newborn starts with good management of the pregnant female, adequate birth conditions, and immediate care. Due date should be estimated in all pregnant females based on the average pregnancy length in the herd. This supposes that the breeding dates are known precisely. Precise breeding records also allow adjustment of nutrition in order to meet pregnancy requirements, especially during the last trimester of pregnancy. In the last month of pregnancy, the dam should be placed in a clean paddock and receive recommended vaccinations (cf. Vaccination). Surveillance of parturition has 3 main objectives: identification of dystocias, evaluation and administration of early neonatal care, and to insure colostrum intake for passive transfer of immunity to the newborn.

Evaluation of the birth process

There is generally no need for intervention during parturition as most births are normal. However, close supervision of the parturient females allows early diagnosis of dystocia and ensures that the newborn is cared for during the first critical hours of life. Immediately after parturition, the dam and newborn should be placed in a quiet area for 24-48 hours to allow establishment of normal bonding so that they learn to identify each other without interference from the rest of the herd. It also allows the newborn to learn to nurse undisturbed and gives the herd manager the opportunity to monitor both the offspring and the dam more closely.

Evaluation and care of the neonate

The umbilicus should be disinfected with 2% - 7% iodine or 0.5% Nolvasan^R. (chlorhexidine) immediately after birth. This treatment is repeated 3 times in the first 24 hours. Evaluation of the neonate includes taking rectal temperature, examination for abnormalities, and evaluation of maturity (cf. Obstetrics and neonatal care). Evaluation of maturity is based on birth date, weight and external appearance. The premature newborn camelidae is small in size and presents a silky coat. In the llama and alpaca, the ears are floppy or tipped because of insufficient cartilage development. The epidermal membrane tends to be very adherent and thickened, especially at the extremities and the foot pads. The teeth are not erupted yet. Premature camelidae also present respiratory difficulty (crackles, rattles or wheezes) and sometimes seem to gasp for air. All premature camelidae will not stand on their feet within the first hours as they should and may remain recumbent for up to 3 weeks. This is caused by insufficient development of the joints and tendons. Some animals may be knock-kneed without being premature, but this condition can be made worse due to excess laxity in the tendons. Tendon laxity can also cause the fetlocks to drop down or the knees (carpal joint) to bend backwards. Premature camelidae require intensive care, especially if they have compromised cardiovascular and respiratory function. Most pre-mature dromedary camels that we have seen continued to lag behind in growth and remained small in size compared to normal animals of the same age. Ocular problems and sometimes complete blindness may be a sequela of premature birth.

Colostrum intake

The newborn should receive 10% of its body weight in colostrum within the first 18 to 24 hours. At least half of this amount should be consumed in the first 6 to 12 hours after birth in order to take advantage of maximal intestinal absorption of colostral antibodies. Newborns that are unable to stand or that have dams lacking sufficient udder development should receive pre-warmed colostrum that has been kept in a freezer (-20° C). In the dromedary, we have successfully used colostrum feeding guidelines similar to those suggested for foals (cf. Obstetrics and neonatal care).

Nutrition

Camelidae are adapted to harsh conditions and are able to withstand food and water deprivation using special physiological mechanisms.)⁽¹⁹⁾ They feed primarily on poor pastures of small shrubs, bushes and perennial graminae. This adaptation to poor grazing conditions is translated into a high digestibility coefficient. The characteristics of digestive physiology and behavior in camelidae have been elegantly reviewed by Engelhardt et al. ⁽²³⁾ Camelidae are able to use pasture efficiently by selecting the most nutritious plants and increasing their digestion by a longer retention in the forestomach. In addition, they have a highly efficient urea recycling mechanism enabling its use for microbial protein synthesis. Finally, they can withstand long periods without water.

In the llama, the dry matter intake averages 1.7 kg with digestibility coefficients of 56%, 59%, and 75% for fat. proteins, and fiber respectively.⁽⁴⁹⁾

Nutritional requirements (practical feeding)

There are very few studies on the nutritional requirements of camelidae. A comparison of llama and sheep food intake and digestibility shows that llamas ingest up to 14% more straw and used it more efficiently than sheep. Efficient use is likely due to an increased mean retention time of dry matter which is 7 hours longer than that of sheep. This peculiarity of digestion allows llamas to take advantage of very poor roughage.⁽²¹⁾

Alpaca's intake is about 1% to 1.5% of their body weight and water intake is 5% to 8%, depending on pasture conditions.⁽⁵¹⁾ Most of the llamas and alpacas can be kept in relatively good condition by pasture feeding alone. In hobby farms, the tendency to overfeed results in obese animals. Supplementation should be given to lactating or growing animals. Diet should contain at least 25% fiber since low-fiber ration can lead to gastric ulcers.

The nutrient requirements for llamas have not been determined as specifically as for most other livestock species which can make ration formulation a challenge. In general, llama nutrient requirements are considered to be similar to those of sheep.⁽⁴²⁾ Llamas will eat from 1.8% - 2.0% of their body weight in dry matter. Normal water consumption for llamas is roughly 4 liters or 1 gallon per 100 lbs. of body weight. Water consumption increases during lactation and hot weather and decreases slightly in colder weather. For llamas and alpacas, the basic ration should consist of 55-65% total digestible protein, 8-10% crude protein, 20-30% crude fiber and 0.6 - 0.8% calcium. Protein and calcium should be increased respectively to 12-14% and 0.8 to 1.0% during lactation and pregnancy.⁽³²⁾ Energy requirement for llamas has been estimated at 256 ± 10 kj. Protein: energy ratio should be approximately
1:10.⁽⁶⁶⁾

Most of fetal growth occurs during the last 2 to 3 months of pregnancy and the requirements for energy, protein, and calcium will increase at this stage by 50 to 60%. Late-pregnancy females will need to eat 1.5 to 2 times the maintenance diet. Therefore, pregnant llamas and alpacas should remain on maintenance diet until the last trimester. Adjustment of nutrition to meet pregnancy requirements should be done progressively over 4-6 weeks in order to prevent metabolic diseases. ⁽³²⁾

Young llamas are generally weaned at 5 to 6 months of age. During this period (and especially during the first 3 months) they rely mainly on their mother's milk for growth. During the peak of lactation, most of the animals will lose body condition if the high milk-production requirements are not met. This loss of body condition can have a negative effect on the ability of the female to conceive during the postpartum period. Nutrient requirements at this stage of production have been estimated at 1.5 to 2.5 times the maintenance level.

In the dromedary, maintenance energy requirements were estimated at 5424 kcal per day for a 300 kg camel or 75 Kcal/ kg^0.75 (metabolic weight) per day.^{(28, 30)} The dromedary uses 68% of the energy content of a ration for body weight gain, which is more efficient than what is observed in other ruminants.⁽²⁸⁾ In most areas where dromedary camels are raised, the animals rely exclusively on pasture. This may explain the poor reproductive performance obtained in most nomadic systems. In more intensively-managed herds, ration calculation usually follows the guidelines for the bovine species. Although this approach is probably not tire best, it is the only one possible until nutritional requirements for this species are well studied. The basic rations fed to dromedary camels consist of 9 to 10 kg of dry matter (about 2% to 2.5% of body weight) and include 8% to 12% protein. In the United Arab Emirates, the basic food stuffs used are medium- to poor-quality hay (8 to 12 kg), bran (0.5 to 1 kg) and crushed barley (0.5 to 1 kg). In other areas of the world, the basic ration contains mainly straw and some grain. In Morocco, most camels receive a feed supplement during parts of the year where pasture conditions are not favorable or when there is an increased work load. Feed used as supplement includes straw (5 to 8 kg), barley (2 to 3 kg), and sometimes sugar-beet pulp or wheat bran.⁽⁶⁰⁾

Some studies have shown that there is high interaction between mineral absorption and quality of the diet. Calcium, magnesium and phosphorus levels improve in camels receiving a well-balanced ration. Trace minerals and vitamin needs for the dromedary camels are not known. Most operations use the same guidelines and feed additives provided for cattle.^(24-26) In some areas special consideration should be given to supplementation treatment with vitamin E and selenium, particularly in young animals.

Requirements for lactation and pregnancy are not yet established for the dromedary. It is known however, that animals fed restricted diets during lactation have decreased plasma glucose levels due to a high demand for lactose synthesis.⁽¹⁹⁾ Most of the females will lose weight during lactation if not fed adequately. This negative nutritional balance during lactation may be responsible for prolonged postpartum anestrus. Pasture intake in suckling camels has been estimated at 5.88 kg of dry matter. Feed intake increases 58% in lactating versus non-lactating animals and can reach up to 1.4 to 1.8% of body weight with crude protein intake of 0.9 kg, 1.1 kg, and 1.6 kg in non-lactating. pregnant, and lactating females respectively.⁽³⁹⁾

Body condition score monitoring

Body condition, or rather the change in body condition, is a very good indicator of the nutritional status of animals. The ideal method for monitoring body condition in animals is by tracking their weight. However, this is not always possible especially in large herds. Body weight in the dromedary can be estimated with relatively good accuracy from some body measurements. In young animals, weight can be estimated with a girth measurement alone⁽³⁷⁾ according to the following equations:

For 6-month-old animals. Weight (kg) = 2.68 x HG (cm) - 217.1
For 2-year-old animals. Weight (kg) = 3.88 x HG -355.4
For 3-year-old animals, Weight (kg) = 4.42 x HG -429.37, where HG = heart girth.

In adult dromedary' camels, the best body measurements for the estimation of body weight are the circumference at the hump, height at the withers, and height at the hump.⁽⁴⁷⁾ The most used equations for the estimation of live weight are:

Weight (kg) = 53xAxBxC
Weight (kg) = 52xAxBxC
Weight (kg) = 6.46 x 10'7 (A + B + C)^3.17

where A = girth over the hump, B = height at the withers and C= thoracic girth.⁽⁶⁰⁾

When these measurements are not possible, the herd nutritional situation can be judged by the change in body condition. Body condition is scored based on a 4-, 5- or 9-point system.⁽¹⁾ The evaluation is subjective but allows a comparison of the condition of the animal during phases of production especially when done by the same individual. The scoring is based on the amount of muscle mass and fat deposition in key areas of the body: thorax, loin, ribs, sternum, withers and in the hump in the case of dromedaries and Bactrian camels (Figure 12.1). We prefer to use a 9-point scoring system to avoid the use of half points which one is often tempted to do in the field. In a 4-point scoring system conception rates were respectively 6%, 52%, 98%, and 95% for animals with BCS 1, 2, 3, or 4.⁽²⁾ Our results of screening several hundreds of dromedary females show that no ovarian activity is observed in animals that have less than a 3 BCS on a 9-point scale.

Evaluation of the body condition score in llamas and alpacas requires feeling the chest area, inspecting the conformation of the chest and front legs, feeling the lumbar area, the ribs, and examining the inner thighs. The pelvis is generally a bad indicator of body condition in the South American camelidae because it tends to always feel bony.
 

The muscle mass and fat deposit of the animal can be evaluated at the level of the lumbar area (loin). In emaciated or thin animals, the vertebrae processes are easily felt with almost no muscular cover which gives a certain concavity to each side of the spine. In optimal condition, the angle over the lumbar muscles is about 45. In obese animals, the tendency is towards a more convex shape due to excessive fat deposition (Figure 12.2). Muscle mass and fat deposit can also be evaluated by the shape of the inner thigh inspected from behind the animal. The space between the rear legs is wide in very thin animals and decreases markedly in fat animals (Figure 12.2). A thin llama will have more space between the rear legs close to the body and less musculature, while a fat llama's upper thighs will touch each other.

Palpation of the ribs is a good indictor of the amount of subcutaneous fat. Under optimal conditions the ribs should be felt without a great deal of pressure with the fingers. The ribs are almost impossible to feel in obese animals. The amount of muscle and fat cover can also be evaluated by the general shape of the chest. In thin animals the chest has an overall "V" shape which becomes more rounded in fat animals.

The ideal body condition varies according to stage of production. In the five-point system, animals should score between 3 and 3.5 at the end of pregnancy and between 3.0 to 4.0 during lactation. The corresponding score in the 9-point system would be 5 and 5 to 6.

Preventive medicine

Disease testing

Several diseases constitute a potential risk for the herd, including brucellosis, tuberculosis, paratuberculosis (Johne's disease), tetanus, enterotoxemia, colibacillosis, actinobacillosis, listeriosis, anthrax and pasteurellosis, ringworm, trypanosomiasis, and mange. Most of these can be prevented by testing and quarantine of newly acquired animals, a sound vaccination program, and regular prophylactic treatments.

Vaccination

Immunization programs have two main objectives - first to protect valuable animals from highly contagious diseases and second to increase colostral antibodies against organisms responsible for neonatal diseases.

In the dromedary, vaccination is seldom used in the traditional system. However, in a more modem operation, vaccination against camel pox, anthrax, rabies and enterotoxemia is widely practiced. However, with the exception of camel pox vaccination, the efficiency of these immunization programs and their effect on productivity have not been thoroughly investigated.

In llamas and alpacas, vaccination is based on the diseases which are present in each geographic area and the vaccines which are effective in other small ruminants (sheep and goats). There are no vaccines which are specifically approved for South American camelidae (Table 3).

Parasite control

Parasite control by drenching or administration of ivermectine should be done at least twice a year. Also, infestation should be monitored by fecal egg count periodically. External parasites, especially ringworm and mange, can be a serious problem in some camel herds. All animals should receive treatment against both internal and external parasites before introduction to the herd.

Foot care

Animals kept on soft ground may need toenail trimming every 6 weeks. In some instances, trimming may be needed 3 or 4 times per year.
 

Overgrowth of toe nails can also be a problem in the dromedary, though with less frequency than for llamas and alpacas.

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