Infertility: A Challenge Exploring Successful Solution

Role of Reproductive Technologies

Good reproductive performance is essential for efficient livestock production, so improvement programs should increase reproductive efficiency to the extent that this can be justified economically. The females must grow rapidly to attain sexual maturity, initiate estrous cycles, ovulate and be mated by fertile males or inseminated with viable semen at the proper time for any chance of conception. At a micro level, each missed heat is a missed opportunity. For each heat missed the farmer incurs a loss of milk production of 21 days, in addition to bearing the feeding cost for animal maintenance. This tantamounts to about Rs.5500. Artificial insemination (AI), which is a normal practice in cattle, is not as successful in buffalo especially in hot summer months, because of the weakness of oestrus symptoms and the variability of oestrus length, which make oestrus detection very difficult. Scientists the world over are working on developing new estrus synchronization protocols which can reduce the ovulation time window post synchronization so as to practice insemination at a fixed time thereby obviating the need for heat detection which is a serious problem especially in buffaloes. The application of two protocols-ovsynch and heatsynch-for estrous synchronization and fixed time AI were successfully attempted in buffaloes (Fig.1 and 2) both in the farm as well as in farmers herds with a success rate for conceptions ranging from 40-50% also in animals suffering from anestrus or repeat breeding.

New Studies on Pregnancy Rates

Research studies on dairy cows have demonstrated that the success rate of the Ovsynch and Heatsynch protocol is dependent on the estrous cycle stage at the onset of the protocol. For example, the initiation of the Ovsynch protocol between days 13 and 17 or early in the estrous cycle (days 2–4) led to a reduced pregnancy rate. Other studies have established that GnRH induced follicular turnover or induction of a new follicular wave is the most efficient if ovulation is induced in response to the first GnRH treatment and that resetting the follicular development can produce a new dominant follicle containing an oocyte with greater potential fertility. Hence, a new estrous synchronization method that includes the administration of an additional PGF2 injection 48 h before beginning the Ovsynch protocol was developed which was named the Doublesynch (the abbreviation of double 

synchronization) protocol, as it resulted in synchronized ovulation after both the first and second GnRH treatments. In a limited study conducted on buffaloes the pregnancy rates were 60% using TAI doublesynch application on cycling buffaloes, and, 55% for anestrus buffaloes, in comparison to 27.3% for cycling buffaloes inseminated following spontaneous estrus. The overall pregnancy success rates after the Doublesynch protocol in both cycling and anestrus buffaloes increased by 30.8% compared to spontaneous estrus (58.1% vs. 27.3%). The study demonstrated that the Doublesynch protocol followed by TAI significantly enhanced the pregnancy rate in cycling and anestrus buffaloes in comparison to untreated controls even during the low breeding season (summer). By substituting the second GnRH injection of the Doublesynch protocol with estradiol benzoate another novel estrous synchronization protocol – estradoublesynch- has recently been developed (Fig.3). Estradiol benzoate has some advantages compared with GnRH (i.e., cheaper hormone price, easier scheduling and implementation for injection and insemination, greater uterine tone, ease of insemination, and occurrence of estrus as has been recorded using the Heatsynch protocol. The success rates in terms of percentage of buffaloes conceived were very similar to that obtained using the doublesynch protocol in buffaloes. The techniques of doublesynch and estradoublesynch hold promise and need to be validated in farmers' herds.

B.S. Prakash, Assistant Director General (AN&P), Animal Science Division, ICAR, Krishi Bhawan, New Delhi-110001

Climate Change: Role of Indigenous Livestock for Sustainable Food Production

The climate change includes sudden major changes in temperature, precipitation, or wind patterns vis a vis the normal conditions during the same period over the years. Under the present paradigm of climate change, global warming is the major issue that has arisen because of ongoing rise in global average temperature near Earth's surface. Increasing concentrations of greenhouse gases like Carbon dioxide, nitrous oxide, methane in the atmosphere that ultimately is causing climate patterns to change abruptly, thus affecting human and animal life both directly causing disease and heat stress as well as indirectly by increased incidences of natural disasters. Earth's average temperature has risen by 1.4°F over the past century, and is projected to rise another 2 to 11.5°F over the next hundred years. These small changes in the average temperature of the planet can translate to much larger and potentially dangerous shifts in climate and weather. Rising global temperatures have often been accompanied by changes in weather and climate. Some places have experienced intense rainfall, resulting in more floods while at other places no rainfall causing droughts, or, as well as more frequent and severe heat waves. The planet's oceans and glaciers have also experienced some big changes - oceans are warming and becoming more acidic, ice caps are melting, and sea levels are rising. As these and other changes become more pronounced in the coming decades, they are likely to present challenges to our society and our environment.

Mega Biodiversity

Traditionally, India has been a mega bio-diversity centre and rearing of domesticated animals was practiced since time immemorial. Almost all the major livestock species including cattle, buffaloes, sheep, goats, pigs, camels, horses, donkeys, yak and mithuns are found in India. Apart from poultry, domesticated species of avian such as ducks, geese, quails, turkey, pheasants and partridges also exist in India. In domesticate species there are over 140 well documented and defined breeds, whereas per FAO watch list there are about 220 breeds. Tharparkar, Sahiwal and Rathi breeds of cattle and camels are indigenous to hot arid deserts where they experience excessive heat during day time in summer when ambient temperature may be as high as 48-50oC. While the same animal stay in open in night when the outside temperature may be as low as 15-18oC. Like-wise yak (Bos grunniens) is found in cold arid desert in upper Himalayas where day temperature may be 35-38oC and night temperature may be sub zero. These highly adapted germplasm have fixed genes and alleles that give them sustenance in world's most inhospitable climate and can serve as excellent experimental model for studies related to animal production under changing climate. It is imperative to identify such alleles and gene combinations in our indigenous livestock breeds and populations and the develop strategies for gene based introgression in other populations which are prone to susceptibility to impending climate change.

Impact of climate change on livestock

Climate change comes as an additional factor affecting a livestock sector that is already highly dynamic and facing many challenges. Important objectives of livestock genetic resource management include ensuring that animal genetic resources (AnGR) are effectively deployed to meet these challenges (i.e. are well matched to the production environments in which they are kept) and that the genetic diversity needed to adapt production systems to future changes is maintained. At the same time, many of the specific challenges associated with climate change (high temperatures, disruptions to feed supplies, disease outbreaks, etc,) as well as the general unpredictability it brings to the future of the livestock sector, highlight the importance of retaining diverse genetic options for the future. Livestock sector is affected by climate change and also contribute in global warming to some extent. Climate change affects livestock both directly and indirectly. The direct effects are due variation in air temperature, humidity, wind speed and other climate factors that influence animal performance viz., growth, milk production, wool production and reproduction. The impact of climate change on animal production has been due to differential availability of feed grain, pasture and forage crop production and quality, health, growth and reproduction and, disease and their spread under abrupt climate change. Thus, an increase in air temperature, such as that expected in different scenarios of climate change, would affect directly animal performance by altering the animal heat balance. There are four modes of energy transfer: radiation, convection, evaporation, conduction, which is governed by several physical parameters control heat transfer by different modes. Air temperature affects energy exchanges through convection and evaporation. When temperature increases, evaporation becomes the most important way of heat loss, since it does not depend on a temperature gradient. Therefore combination of temperature and humidity acquire more relevance, since humidity enhances temperature effects. Therefore, it is important to evaluate the environment, from the heat stress stand-point, through the temperature humidity index (THI). Dairy cattle show signs of heat stress when THI is higher than 72. The comfort limit depends on level of production, type of germplasm and its longevity under given conditions. Animals presenting higher level of production are more sensitive to heat stress. It is not only intensity of stress, but also the length of the daily recovery period is important in determining animal responses to climatic stresses. They fail to dissipate the extra heat load accumulated during days when there are several hours with THI well above the comfort limit, and little opportunity to recover. Climate change is likely to lead to changes in disease epidemiology, severity of outbreaks and spread to other areas. Precise effects of climate change on disease profile are difficult to predict, but combined with problems in the sustainability of some conventional disease control programmes, climate change-related effects are likely to increase the importance of genetic resistance and tolerance to diseases. Changes in the distribution and incidence of diseases that kill large numbers of animal or induce culling measures for disease control may pose additional threats to animal genetic resources diversity. The poor farmers can adapt to the local scale effects of climate change to some extent but feed supply by commercial producer is also affected due to dependence on

world feed markets and that is again vulnerable to the effects of climate change, especially on prices.

Sustainability of livestock especially, the exotic breeds or their crossbreds depends on better feed and fodder resources in adequate quantity is influenced more critically than the indigenous ones. The indigenous breeds have lesser feed/fodder requirements, able to utilize coarser feed/ fodder resources and can graze on meagre grazing resources that too when the ambient temperature is high. Therefore, the types of germplasm, their adaptability under different climate regimen are keys for sustainability especially under impending climate change.

Studies on impact of climate change in Indian livestock

The vulnerability of livestock to climate change has hardly been documented in India. Isolated experimental studies have been conducted on effects of season and climate on production, performance and other physiological parameters of dairy animals. From these studies it has been revealed that milk yield of crossbred cows in India (e.g., Karan Fries, Karan Swiss and other Holstein and Jersey crosses) are negatively correlated with temperature-humidity index. The influence of climatic conditions on milk production has been also observed for local cows which are more adapted to the tropical climate of India. Heat stress has been found to have detrimental effects on the reproduction of buffaloes, although buffaloes are well adapted morphologically and anatomically to hot and humid climate. The thermal stress on Indian livestock particularly cattle and buffaloes have been found to decrease estrus expression and conception rate. The length of service period and dry period of all dairy animals was found to be increased from normal during drought. The outbreak of the disease has often been correlated with the mass movement of animals which in turn is dependent on the climatic factors. The higher incidence of clinical mastitis in dairy animals during hot and humid weather

may be due to increased heat stress and greater fly population associated with hot–humid conditions.

Mitigation strategies

Since climate change could result in an increase of heat stress, all methods by which animals can cope with heat stress or alleviate the impacts of heat stress to mitigate the impacts of global change on animal responses and performance need to be assessed. Three basic management schemes for reducing the effect of thermal stress have been suggested: (a) physical modification of the environment; (b) genetic development of less sensitive breeds and (c) improved nutritional management schemes.

Physical modification of the environment

The different methods of environmental modification include: shades, ventilation, combination of wetting and ventilation. Providing shades to livestock is the simplest method to reduce the impact of high solar radiation. Shades can be either natural or artificial. Tree shades have proved to be more efficient. In traditional livestock rearing, animals are herded under the shade of trees in pasture or in forests during peak summer hours. When enough natural shade is unavailable, artificial structures may be constructed. Different aspects concerning design and orientation of shades have been published. Shades are effective in reducing heat stress in the dairy cow. Animals presented lower afternoon rectal temperature and respiration rate, and yielded more milk and protein when provided adequate shade. The artificial shade structure using heat proof materials may not differ from tree shades, in terms of the effects on animal well-being. Increase in air movement is an important factor in the relief of heat stress, since it helps heat loss due to air convection especially under high ambient humidity leading to evaporative cooling. Wherever possible, natural ventilation should be maximized by constructing open-sided constructions. Forced ventilation, provided by fans, is a very effective method, if properly designed. An effective way of cooling cattle is spray evaporative cooling. There are several methods available: mist, fog and sprinkler systems. However, the single use of a sprinkler and fan system, for 30 minutes before milking, has proved to be useful to relieve dairy cow's heat stress. In 2030, adoption could restrict losses to 1% of annual production. Finally, in 2070, milk losses would be reduced to 3 to 4% of annual milk production, by installing environmental modifications.

Genetic development of less sensitive breeds

The strategies should be to explore all the livestock breed populations keeping following points in to consideration.

•Documentation of indigenous breeds for heat tolerance, disease resistance, adaptation to poor diet, etc. and their comprehensive evaluation of performance and use of animals in specific production environments;

•Phenotypic characterization studies on Animal Genetic Resources (AnGR), the surveys should have data entry on all phenotypic traits specifically;

•Improving knowledge and awareness of, and respect for, local and indigenous knowledge relevant to climate-change adaptation and mitigation;

•Identifying potential climate change-related threats to specific AnGR, ensuring that long-term environmental threats are monitored and that urgent action is taken to address immediate threats from climatic disasters to save small populations at severe risk;

•Modelling the future distribution and characteristics of production environments, to support the assessment of threats and the identification of areas that may be suitable for particular breeds in the future;

•Improving knowledge of breeds for their current geographical distributions and to facilitate planning of climate-change adaptation measures and AnGR conservation strategies;

Improving the availability of the above-described knowledge, including via DAD-IS and other AnGR

information systems.

Improved nutritional management schemes

The effects of climate change on livestock production can be mediated through change in feed resources and feeding schedules. It is known that feed resources can have a significant impact on livestock productivity, the carrying capacity of rangelands, the buffering ability of ecosystems and their sustainability, prices of grains, trade in feeds, changes in feeding options, grazing management and ultimately the control on greenhouse gas emissions. There are considerable opportunities to reduce the methane emissions per animal by individual and herd management changes that reduce the proportion of energy spent in maintenance. Maximised fecundity, health and maximising daily product output by provision of ad libitum high digestibility feed or specific supplementation for enhancing digestibility of coarse feeds and fodders. Reducing total emissions (kg/d) rather than simply emission intensity (methane/product) from the herd or flock will require reduction in animal numbers or implementing mitigation strategies such as the inclusion of fats or oils in the diet. Potential exists to reduce emission without restricting animal performance by grazing pastures of lesser tannin levels or by supplementing with oils or white cotton seed and by some small supplementations of tannin and saponins. Pasture quality, supplementation and selection for NFI are potential means of reducing the emissions intensity and total methane emissions from livestock. Efficiency of the whole herd or flock can also be improved by further increasing productivity of stock and minimising the proportion of consumed energy utilised in maintenance. The climate change could affect animal production and well-being, especially because of increases in air temperature. However, the knowledge of animal responses to heat stress during the hot months in several areas of the world, as well as during extreme heat events, may be used to evaluate the impacts of global change. Some current practices and adoptions to reduce heat stress in dairy cows, such as shades, sprinklers and ventilations will be suitable for mitigating climatic change effects if the economics of heat stress management do not change radically. However, farmers are not quite aware about the impacts global warming can produce in their operation. Therefore, good research work is needed to help them take strategic and tactical decisions. National Initiative on Climate Resilient Agriculture (NICRA) launched by Indian Council of Agricultural Research (ICAR) with the funding from Ministry of Agriculture, Government of India has three major objectives of strategic research, technology demonstrations and capacity building. Assessment of the impact of climate change simultaneous with formulation of adaptive strategies is the prime approach under strategic research across all sectors of agriculture, dairying and fisheries. Evolving climate resilient agricultural technologies that would increase farm production and productivity vis-à-vis continuous management of natural and manmade resources constitute an integral part of sustaining agriculture in the era of climate change.

Source of Article: Book on Climate Change and Sustainable Food Security Author: K.M.L. Pathak, Neelam Gupta, Vineet Bhasin, Rajan Gupta, S.C.Gupta and

B.S. Prakash, ICAR (Indian Council of Agricultural Research)

Treating infertility, a common problem in cattle

Reproduction is the first system to be affected by malnutrition

Right Nutrition

Cattle should be fed with a well balanced diet to increase conception rate. Infertility In cattle accounts for major economic losses in dairy farming and dairy industry in India. Maintaining an infertile animal is an economic burden and in most countries such animals are driven to slaughterhouses. In cattle, nearly 10-30 per cent of lactations may be affected by infertility and reproductive disorders. To attain good fertility or high calving rate both the male and female animals should be well fed and free from diseases.

Many reasons

The causes of infertility are many and can be complex. Infertility or failure to conceive and give birth to a young one can be due to malnutrition, infections, congenital defects, management errors and ovulatory or hormonal imbalances in the female, according to Dr. Cecilia Joseph, Associate Professor,Department of Clinics, Madras Veterinary College,Chennai.

Sexual cycle

Both cows and buffaloes have the sexual cycle (oestrus) once in 18-21 days for 18-24 hours. But in buffaloes, the cycle is silent posing a big problem to the farmers. Successful heat deduction is possible only when the animals can be properly identified when they come in

oestrus (heat), proper maintenance of records and proper training of staff. The farmers should closely monitor the animals 4-5 times from early morning to late night. Poor heat deduction can cause increased levels of infertility. Considerable skill is needed to deduct the animals in heat for visible signs. Farmers who maintain good records and spend more time watching the animals obtain better results. "To avoid fertilization failure, breeding should be done during the oestrus period. Animals that do not show oestrus or do not come to cycle should be checked and treated," she said. Deworming once in 6 months should be done for worm infestations to maintain the health status of the animals.

Periodic deworming

A small investment in periodic deworming can bring greater gains in dairying. Generally vaccinations are avoided during pregnancy. For successful dairy farming, nutrition plays an important role.

Balanced diet

Cattle should be fed with a well balanced diet with energy, protein, minerals and vitamin supplements. This helps in increased conception rate, healthy pregnancy, safe parturition, low incidence of infections and a healthy calf. Care of young female calves with good nutrition helps them to attain puberty in time with an optimum body weight of 230-250 kgs, suitable for breeding and thereby better conception, explained Dr. Cecilia Joseph.

Feeding adequate quantity of green fodder during pregnancy will avoid blindness in newborn calves and retention of placenta (after birth). In natural service, breeding history of the bull is very important to avoid congenital defects and infections. Infections of the uterus can be largely avoided by having cows served and calved under hygienic conditions. After 60-90 days of insemination, the animals should be checked for confirmed pregnancy by qualified

veterinarians. When conception occurs, the female enters a period of anestrus (not exhibiting regular oestrus cycles) during pregnancy. The gestation (pregnancy) period for cow is about 285 days and for buffaloes, 300 days.

Avoid transportation

Unwarranted stress and transportation should be avoided  during the last stages of pregnancy. The pregnant animal should be housed away from the general herd for better

feeding management and parturition care, they elaborated. Pregnant animals should be drained of their milk two months before delivery and given adequate nutrition and exercise.

This helps in improving the health of the mother, delivery of a healthy calf with average birth weight, low incidence of diseases and early return of sexual cycle.

Breeding cycle

Breeding can be started within four months or 120 days after delivery to achieve the goal of one calf per year for economic and profitable dairy farming, according to them.

Dr. T. Senthilkumar, Assistant Professor, Directorate of Extension

Education, TANUVAS, Chennai - 600 051, Tamil Nadu

Animal Feeding Strategy under Current Feed Scarcity Scenario

Introduction

India is endowed with world's largest and most diverse asset of livestock in terms of species and breeds within the species. It posses one of the world's best dairy buffaloes, draught cattle, carpet wool sheep and highly prolific goat breeds. India has a share of 2.4% of the world's areas with 15% and 17.5% of world livestock and human population respectively. The number of livestock per hectare is 1.58 and there is one livestock per 2.1 human beings in the country. Because of large human 

population, there is huge demand for land for food in the country, and there is a stiff competition for food between humans and animals. The food grains chiefly wheat, paddy, maize, barley, bajra, jowar and ragi are grown for human consumption and only a smaller part is meant for livestock and poultry feeding, a chunk of which is again diverted towards feeding of poultry and swine. Apart from this feed grains, oil cakes and by-products are one of the chief components of the concentrate feeds commonly fed to ruminant livestock. Cottonseed cake and meal are often used in cattle feed throughout the country followed by rapeseed meal whereas groundnut meal is less popular because of aflatoxin problem. Though the oil cakes are supposed to be rich in protein and energy, the real scenario is something different. In commercial feed preparations, the cakes used are mostly solvent extracted which have been already drained out of maximum oil for human consumption and hence 

contain negligible oil content. The problem of adulteration in oil cakes viz. groundnut husk for cake, ureas for soybean meal, argemone for mustard seed etc. is also present. Unlike solvent extraction process during expeller processing, a lot of heat is generated which detoxifies some of the naturally prevalent toxic principles viz. gossypol in cottonseed cake, glucosinolates in mustard seed cake, rapeseed cake and protease in soybean meal etc. By considering the above it is clear that solvent extracted cakes are of poor quality and thus of low nutritive value. Another inherent issue is regarding the import policy of oil cakes in India. India regularly imports edible oil instead of the intact oil seeds which creates problems for the country's crushers, with the solvent extraction units running at only 50% of capacity. Another chief and usual ingredient of ruminant ration is fodders and forages, which are again short in supply. Currently, there is scarcity of land for fodder cultivation giving rise to a deficit of 25% dry fodder, 20% green and 32% deficit of concentrate mixture (NIANP, 2012) and the gap between requirement and availability is predicted to rise further. Since years a large proportion of our animals are underfed. Through natural selection and human interventions though those animals rose into stress tolerant and optimal producing breeds but gene responsible for economical traits might have been suppressed. So, the concern regarding nutrition of animals need to be taken more seriously by all groups of animal science researchers.

Strategies undertaken to solve the animal feed scarcity issue

Improving productivity in areas already under fodder cultivation, improving productivity of grazing and pasture ands, raising perennial fodder crops on field bunds and boundaries, peri-urban areas and exploiting ununtilized and under-utilized fodder crops are some of the promising options to enhance fodder availability. In 12th five year plan period promotion of fodder cactus in arid ecosystem especially in states of Rajasthan and Gujarat is taken up. Accelerated fodder development programme taken up by the Ministry of Agriculture (2011) aims at accelerating production of fodder through promotion of integrated technologies and processes by production of quality seeds and organized demonstration of appropriate forage equipments through state Agricultural Universities and adoption of technologies like fodder block making units, chaff cutter for fodder processing and silage making. Silage has nutritive value comparable or slightly lower than that of green forage. Corn silage is a very good source of fodder for dairy animals. It can be complemented with a protein source such as Lucerne fodder or urea while making silage. Reports suggest that corn silage provides adequate energy for growing cattle and buffalo. Variation in fodder availability and quality year through reduces the intake and digestibility due to change in microbial population during the transit of fodder, which can be avoided by silage feeding. Silage processing reduces the daily wages towards labour for cutting and transport of fodder from field to farms and also leaves the field open for new crop sowing leading to efficient utilization of land. Thus, more crops could be obtained from limited land. Another very easy energy saving method of fodder preservation in tropical climate without compromising quality is by drying the fodders before reaching maturity in the form of hay. Mostly fodders like Lucerne, oat, cowpea, berseem etc. Are dried for hay making . Progressive farmers in Punjab state report that guinea and Lucerne hay could exclusively support milk yield up to 10 litre. Over the years, 

considerable technological advancement has taken place in the feed and fodders focus in gon enhancement of their nutritional quality and subsequently productivity enhancement. One such very effective and well adopted technology is bypass nutrient technology which has been taken up by private feed manufactures as well as National Dairy Development Board (NDDB) and dairy federations. Its benefits have percolated to the ground level. The area specific mineral mixture technology has also helped to a considerable extent in overcoming the problem of infertility at field level. The livestock productions systems in India predominantly sustain on feeding of crop residues. Fodder and crop residue enhancement and densification are also the strategies adopted to solve the issue of their poor nutritive value. In Feb 2012, National Dairy Plan I (NDP-I) was initiated to achieve the objective of 150 million ton milk yield by the year 2016-17 under which along with production of high genetic merit bulls, semen production, doorstep AI emphasis was laid upon ration balancing and fodder development programme. Unless provided balanced diet, it's not possible to exploit the genetic potential of animal for higher productivity. The rations balancing can be done with the feed ingredients available with the farmer with extra addition of some minerals, vitamins and some concentrate feeds to fill the deficit of energy and protein in the ration leading to least cost ration formulation and also efficient utilization of locally available feed resources. Research and field trials conducted with this idea lead to increased milk yield, reduced cost of milk production along with reduced methane emission. Under fodder development programme, focus is laid upon improving productivity of fodder crops and common grazing lands and conservation of surplus green fodder for availing during lean season. Local resource persons demonstrate silage making and re-vegetation of common grazing lands with high yielding cultivated fodder crops, grasses and pasture legumes. Crops residues form the chief basal diet of the Indian ruminant livestock though they are not sufficient or balanced regarding their nutritive value. Hence, they can be enriched with cakes, brans, grains, molasses, hay and minerals and then densified into blocks. This aspect of enriching the poor quality feeds is also undertaken in NDP-I. Such densified blocks can be produced and transported at cheaper cost compared to the crop residues and areas to achieve optimum production from the animals. Scientists at IGFRI, Jhansi made the process easy, simple by adding a gadget to existing threshing machine used in the wheat-fields which lead to wheat straw treatment in the field without any additional cost (CAR News, Jan-March, 2014). The scarcity of crop residues is likely to rise in due course, since a part of cellulose rich crop residues are partitioned towards paper mill, plywood industry etc. since fibrous feeds are usual in ruminant ration, there is need to explore additional similar resources. Plant breeders in India have identified a number of varieties/hybrids which could give a better quality and higher yield of crop residue without any compromise in grain yield. This would provide an opportunity for augmenting the availability of fodder from crops like pearl millet, sorghum, maize and oats. Development of many interspecies hybrids in Trifolium is in progress in IGFRI, Jhansi. Systemic forage crop breeding programme at ICAR institutions and State Agricultural Universities have led to development of a large number of improved varieties of forage crops suitable for different agro-ecological zones. Integrated fodder production system can also be adopted to adjust the cultivation of fodder crops with that of main crops and harvest them as per the needs. This can easily be practiced by all classes of farmers under both irrigated and rainfed conditions. A plant like Azolla contains 25-30% protein, 10-15% minerals and 7-10% of amino acids on dry matter basis and is rich in essential amino acids, vitamins (vitamin A, vitamin B12 and ß-Carotene), growth promoter metabolites and minerals like Ca, P, K, Fe, Cu, Mg etc. It has been tested to be palatable to cattle and other ruminants with a potential to increase milk production by 15-20% in milch cows. Aqua plants and vegetable wastes can be very good alternative feed resources for ruminant feeding after reducing the moisture content to certain limit. With the scarcity in land for fodder cultivation of aqua plants and their field trials. As regards aquatic cultivation one of the emerging technology of fodder cultivation is hydroponics. It is a method of growing plants in water using mineral nutrient solutions and no soil. Terrestrial plants may be grown with their roots in the mineral nutrient solution only. Through the concept of hydroponics is an old one, it has been attracting interest from feed manufactures. Fruits and vegetable wastes viz. carrot fresh tops and pomace, carrot wet, cauliflower leaves, sweet potato, tomato pomace dried, tomato pulp, citrus pulp, baby corn husk and fodder, bottle gourd pulp, banana peels, muskmelon peels and watermelon peels are produced on a large scale from processing industries. As per FAO (2012) fruit and vegetable processing, packing, distribution and consumption in the organized sector in India generate a total of approximately 1.81 million tones of fruit and vegetable wastes. A large proportion of these wastes are dumped in landfills or rivers, causing environmental pollution. Alternatives to such disposal methods could be recycling through livestock as feed resources or further processing to extract or develop value-added products which will economize the animal feed and also alleviate the environmental pollution associated with disposal of fruits and vegetable wastes.

Conclusion

Feed scarcity is a major challenge to livestock sector in India. So far though various strategies have been adopted to combat the existing problem, but it has not yet reached to farmers levels. So, there is need to rigorously implement the strategies at all levels of ruminants feeding system. Improved utilization of straw, stover and crop residues are very important. Fodder variety development with emphasis on multi-cut needs attention. By products of Food industry and their utilization in ration balancing should reach the needy dairy farmers. Hay and silage preparations and feeding can also solve the problem during lean periods.

Sonali Prusty (Ph.D. Scholar, DCN Division, NDRI, Karnal)

Vijay Kumar Sharma (SMS, J&K)

Akash Mishra (Ph.D. Scholar, DCN Division, NDRI, Karnal)

S.S.Kundu (Principal Scientist, DCN Division, NDRI, Karnal)

Approach 5000+ Veterinarians/ Animal Health Experts

ANIMAL MANAGMENT DURING SUMMER STRESS

Introduction

Dairy animal produce milk most efficiently in environments where they can maintain their body temperature at around 38oC. Tissue and cellular metabolism and the underlying biochemical reactions that sustain life and productive functions need body temperature to be maintained within very narrow limits. Relatively small increases in body temperature of at least 1oC result in detectable, deleterious effects on metabolism and tissue integrity, in particular, the breakdown of body protein and a significant depression in production. The condition resulting in this, where heat load on the body of the animal exceeds heat dissipation is called heat stress. The dairy animal, dissipates heat by two distinct methods; evaporative and non-evaporative pathways.

Evaporative cooling is mainly effected through sweating and respiration. Heat stress itself is a function of time, temperature and humidity, because animal rely on water evaporation via sweating and panting to dissipate an excess of heat they have generated metabolically or absorbed from the environment. The primary factors that cause heat stress in dairy animal are high environmental temperatures and high relative humidity. In addition, radiant energy from the sun contributes to stress if animals are not properly shaded. As the environmental temperature increases, the difference between the temperature of the animal surroundings and their body decreases and her reliance on evaporative cooling (sweating and panting) to dissipate body heat increases. However, high relative humidity reduces the effectiveness of evaporative cooling and during hot, humid summer weather, the animal cannot eliminate sufficient body heat and her body temperature rises. The tremendous amount of body heat that the high yielding dairy cow produces is helpful in cold climates but is a severe liability during hot weather and in hot climates. The physical heat production of an animal is also

controlled by both internal factors and external factors of an animal. Internal heat load comes from basic functions such as respiration, digestion, as well as other daily maintenance requirements. These factors will be influenced by stage of lactation, production levels, as well as quantity, quality and type of feed consumed. External physical heat loads are management factors that affect physical activity and performance. Animal comfort, layout of facilities, stocking densities and fly control can all impact on the animal external physical heat load. Buffaloes are more prone to heat stress than cattle due to scarcely located sweat glands, black color and sparse hair on body surface. The sweat glands of buffalo skin have a low blood supply, number of sweat glands per unit area of skin is about one third of that of cattle and the thickness of corneum layer and epidermis is about double that of cattle.

The thickness and the black pigment of the buffalo skin help in absorption of more heat and leads to disproportionate convective and radiative heat losses from the extremities during exposure to solar radiation.As mentioned earlier, heat load will increase as temperature, humidity and solar radiation increase and air movement decreases.

Effect of heat stress on animals

Under heat stress, a number of physiological and behavioral responses vary in intensity and duration in relation to the animal genetic makeup and environmental factors. The degree to which an animal resists rise in temperature varies with species because of difference in their heat regulation mechanism. When animals are exposed to rising air temperature, the first response observed was increase in respiration rate. Air temperature up to around 300C has little effect on respiration rate and rectal temperature. At higher temperature above 410C, rectal temperature of animal will increase rapidly, while the respiration rate rises rapidly to about 3-4 times the normal values. Under thermal stress, animal employs moderate level of sweating and resort to open mouth panting. Thermal stress lowers feed intake of animal which in turn reduces their productivity in terms of their milk yield, body weight and reproductive performance. Under thermoneutral environmental conditions, most of the large domestic animals are able to maintain equilibrium between heat production and heat loss. High heat loads may lead to energy deficit, even when they do not induce a marked reduction of feed intake in animals.

Strategies for ameliorating heat stress

The effects of heat stress are costly to dairy farmers, but there are opportunities to recover some of the losses to hot weather. Physical modifications of environment, genetic development of breeds that are less sensitive to heat and nutritional management are the three major key components to sustain production in hot environment.

1. Shelter management

With the help of managemental tools, it is possible to modify the microenvironment to enhance heat dissipation mechanism to relieve heat stress.

(a)Scientific construction of animal shed so the air movement will not be hampered

(b) Provide comfortable micro-environment to animals.

(c) Use of cooling ponds, water sprinkler system and whole body bathing.

(d) Use of cooler for cooling of animal sheds.

There is no doubt that shading is one of the cheapest ways to modify an animal's environment during hot weather. Although shade reduces heat accumulation, there is no effect on air temperature or relative humidity and additional cooling is necessary for farm animals in a hot humid climate.

2. Nutritional management

It has been documented that both low and high ambient temperature cause oxidative stress. Oxidative damage, as a result of heat stress may be minimized by antioxidant defense mechanisms that protect the cells against cellular oxidants and repair system that prevent the accumulation of oxidatively damaged molecules. Antioxidants, both enzymatic and non-enzymatic, provide necessary defense against oxidative stress as a result of thermal stress.

I.Non enzymatic antioxidants in reducing oxidative stress

a)Vitamins

Both vitamin C and vitamin E have antioxidant properties. Antioxidant vitamins have proved to protect the biological membranes against the damage of ROS and the role of vitamin E as an inhibitor –“chain blocker”- of lipid peroxidation has been well established. Like vitamin E,ascorbate is also a chain breaking antioxidant. It prevents lipid peroxidation due to peroxyl radicals. It also recycles vitamin E. It protects against DNA damage induced by H O radical. Vitamin C has a paradoxical effect as it can also produce ROS by its action on transition metal ions. Both ascorbate and zinc are known to scavenge reactive oxygen species (ROS) during oxidative stress. Vitamin C was found to assist in absorption of folic acid by reducing it to tetrahydrofolate, the latter again acts as an antioxidant. Use of folic acid is impaired when vitamin C is deficient.

b)Minerals and trace elements

Zinc and other trace elements like copper and chromium act as typical antioxidants as they work indirectly. Zinc is a catalytic cofactor for Cu/Zn SOD and catalyzes dismutation of superoxide anion, producing molecular oxygen and H2O2, the latter product is usually metabolized by GPx and CAT. The activity of Cu/Zn SOD, CAT and GPx is decreased in copper deficient animals. It is also reported that normal copper levels are necessary to maintain the structural integrity of DNA during oxidative stress. Supplementation of electrolytes is one among the nutritional strategies to combat heat stress in animals. Addition of Na+, K+ and Cl- is benefited in heat stressed dairy cows in terms of milk yield, acid base balance and altered temperature. Supplementation of sodium and potassium in the form of bicarbonate/carbonate also help in better regulation of acid-base balance in the blood.

3.Amelioration through immunomodulation by dietary supplement

The immunostimulant effect of antioxidant depends on age and immune state of organisms.The effect of heat stress can be neutralized by complex antioxidant system that can organism develops. The antioxidant system can be booked by supplementing antioxidants in diet. Vitamin C and trace minerals like zinc have proved to play a vital role as modulators of antibody response and enhances of wound healing in domestic animals.

Ajeet Kumar & Anil Gattani, Assistant Professor,

Department of Veterinary Biochemistry, Bihar Veterinary College, Patna

MASTITIS: CHALLENGES AND SOLUTIONS

Introduction

One of the reasons for low productivity is poor animal health, particularly, mastitis which is single largest problem in dairy animal in terms of economic losses in India as well as all over world.

Bovine Mastitis

 mastitis is an inflammation of the mammary gland in response to injury for the purpose of "destroying or neutralizing the infectious agents and to prepare the way for healing and return to normal function.

Inflammation

can be caused by many types of injury including infectious agents and their toxins, physical trauma or chemical irritants. In the dairy cow, mastitis is nearly always caused by microorganisms; usually bacteria, that invade the udder, multiply in the milk-producing tissues, and produce toxins that are the immediate cause of injury." The teat end serves as the body's first line of defense against infection. A smooth muscled sphincter, which surrounds the teat canal, functions to keep the teat canal closed, prevent milk from escaping, and prevents bacteria from entering the teat. The cells lining the teat canal

produce keratin, a fibrous protein with lipid components (long chain fatty acids) that have bacteriostatic properties. This keratin forms a barrier against bacteria. During milking, bacteria may be present near the opening of the teat canal, either through dirty and wet conditions at the teat end, through teat end lesions or colonization, on contaminated surfaces of milking units. Trauma to the teat renders it more susceptible to bacterial invasion, colonization, and infection because of damage to keratin or mucous membranes lining the teat sinus. The canal of a damaged teat may remain partially open. Conditions that are associated with high impact force against the teat end propel bacteria through healthy teat ends. This includes liner slips caused by excessive temporary vacuum losses, low vacuum reserve or level, and abrupt milking unit removal without shutting off vacuum, as well as vacuum fluctuations caused by inefficient vacuum regulation, blocked air vents, restrictions in the short milk tube, poor cluster alignment, or poor liner condition. After milking, the sphincter muscle in the teat canal remains dilated for 1-2 hours and bacteria present during this time can enter the teat canal. Examples would be dirty housing or environment, or failure to use teat dipping properly. An inflammatory response is initiated when bacteria enter the mammary gland and this is the body's second line of defense. These bacteria multiply and produce toxins, enzymes, and cell-wall components which stimulate the production of numerous mediators of inflammation by inflammatory cells. The magnitude of the inflammatory response may be influenced by the causative pathogen, stage of lactation, age, immune status of the cow, genetics , and nutritional status. Polymorphonuclear neutrophil (PMN) leukocytes and phagocytes move from bone marrow towards the invading bacteria and are attracted in large numbers by chemical  messengers or chemotactic agents from damaged tissues. Masses of PMN may pass between milk producing cells into the lumen of the alveolus, thus increasing the somatic cell count (SCC) as well as damaging secretory cells. Somatic cells consist mainly of PMN or white blood cells. At the infection site, PMN surround the bacteria and release enzymes which can destroy the organisms. The leukocytes in milk may also release specific substances that attract more leukocytes to the area to fight the infection. Numbers of somatic cells remain in large concentrations after bacteria are eliminated until healing of the gland occurs. Clots formed by the aggregation of leukocytes and blood clotting factors may block small ducts and prevent complete milk removal. Damage to epithelial cells and blockage of small ducts can result in the formation of scar tissue in some cases, with a permanent loss of function of that portion of the gland. In other cases, inflammation may subside, tissue repair may occur, and function may return in that lactation or the subsequent one.

Mastitis Causing Bacteria

Disease causing bacteria are often referred to as pathogens. The most common mastitis pathogens are

found either in the udder (contagious pathogens) or the cow's surroundings (environmental pathogens), such as bedding, manure, soil, etc. Contagious mastitis pathogens (Staphylococcus aureus, Streptococcus agalactiae) are spread from infected udders to "clean" udders during the milking process through contaminated teatcup liners, milkers' hands, paper or cloth towels used to wash or dry more than one cow, and possibly by flies. Although new infections by environmental pathogens

(other streptococci such as Str. uberis and Str. Dysgalactiae and coliforms such as Escherichia coli and Klebsiella) can occur during milking, primary exposure appears to be between milkings. Coliform infections are usually associated with an unsanitary environment (manure and/or dirty, wet conditions), while Klebsiella are found in sawdust. About 50% of environmental streptococci infections display clinical symptoms. Sixty to 70% of environmental pathogen infections exist for less than 30 days and are not easily detected. Subclinical infections are those in which no visible changes occur in the appearance of the milk or the udder, but milk production decreases, bacteria are present in the secretion, and composition is altered. There exits a negative relationship between SCC and milk yield. Many of the cows with SCC over 200,000 may have subclinical mastitis.

Effect on Milk Composition

Mastitis resulting from major pathogens causes considerable compositional changes in milk, including

increases in SCC. The types of proteins present change dramatically. Casein, the major milk protein of high nutritional quality, declines and lower quality whey proteins increase which adversely impacts dairy product quality, such as cheese yield, flavour and quality. Serum albumin, immunoglobulins, transferrin, and other serum proteins pass into milk because vascular permeability changes. Lactoferrin, the major antibacterial iron-binding protein in mammary secretions, increases in concentration, likely because of increased output by the mammary tissue and a minor contribution from PMN. Milk protein breakdown can occur in milk from cows with clinical or subclinical mastitis due to presence of proteolytic enzymes. Plasmin increases proteolytic activity by more than 2-fold during mastitis. Plasmin and enzymes derived from somatic cells can cause extensive damage to casein in the udder before milk removal. Deterioration of milk protein as a result of mastitis may continue during processing and storage. Mastitis increases the conductivity of milk and sodium and chloride concentrations are elevated. Potassium, normally the predominant mineral in milk, declines. Because most calcium in milk is associated with casein, the disruption of casein synthesis contributes to lowered calcium in milk.

Effect on dairy industry

Mastitis is responsible for heavy economic losses due to reduced milk yield ( up to 70%), milk discard after treatment (9%), treatment costs (75), premature culling (14%), decrease in milk quality and price due to high bacterial / somatic cell count, increased risk of subsequent mastitis, herd replacement, antibiotics residue in milk and its products and rejection by processor and consumer. Though cows with clinical mastitis have more dramatic changes in milk yield and composition than cows with subclinical mastitis, the losses due to latter are more severe than those due to the former. The Indian diary industry suffers and annual loss of approximately 526 millions dollars due to mastitis, 70% of which is due to subclinical  mastitis.

           

Diagnosis

While acute clinical mastitis is easily suspected/recognized While acute clinical mastitis is easily suspected/recognized even by farmers and is readily diagnosed due to udder swelling, pain and drastic decrease in milk production, the sub-clinical mastitis has neither visual abnormalities in the mammary gland (swelling, hotness, cracks etc.) nor in the milk (blood, clots, flakes etc.). Therefore, routine physical examination of udder and diagnostic screening tests for early detection of mastitis and proper treatment of affected animal are of paramount importance in order to minimize losses due to sub-clinical and clinical mastitis.

Treatment and control: The treatment of the Mastitis is definitely more expensive than its control. Needless to mention in Clinical Mastitis parenteral and intra-mammary antibiotics are used. The word of caution is the judicious use. The intra-mammary use of antibiotics should be avoided to the best possible extent as this is likely to create more damage to udder.

Some of the control measures are as mentioned below:

1. The best possible way is to regularly examine the udder milk for possibility of Sub-Clinical Mastitis.

2. The udder and the teats should be washed pre and post milking with clean water.

3. Herbal teat-dip should be used for cleaning and disinfecting the udder.

4. Post diagnosis of Sub-Clinical Mastitis. Mastilep should  be applied with gentle hand on udder during post milking.

5. The Veterinarian should be consulted for farm management, prevention/control and treatment of mastitis.

Conclusion

Mastitis not only reduces the productive capacity of the cows, it is also expensive to treat. Therefore, its prevention should be the prime concern of each farmer. Effective mastitis control strategies including prudent use of antibiotics, adequate strategies including prudent use of antibiotics, adequate housing with proper sanitation and regular screening for early detection and treatment, follow up of chronic case, culling of older cows with repeated attacks, avoiding consecutive milking and susceptibility testing of the mastitis pathogens before treatment are recommended to alleviate the problem.