# The Author(s) 2020 Abstract
This study focuses on heatstress conditions for dairycattleproduction in WestAfrica under current and future climatic conditions. After testing the accuracy of the dynamically downscaled climate datasets for simulating the historical daily maximum temperature (Tmax) and relative humidity (RH) in WestAfrica for 50 meteorological stations, we used the dataset for calculating the temperature-humidity index (THI), i.e., an index indicating heatstress for dairycattle on a daily scale. Calculations were made for the historical period (1981–2010) using the ERA-Interim reanalysis dataset, and for two future periods (2021–2050 and 2071–2100) using climate predictions of the GFDL- ESM2M, HadGEM2-ES, and MPI-ESM-MR Global Circulation Models (GCMs) under the RCP4.5 emission scenario. Here, we show that during the period from 1981 to 2010 for > 1/5 of the region of WestAfrica, the frequency of severe/danger heat events per year, i.e., events that result in significant decreases in productive and reproductive performances, increased from 11 to 29–38 days (significant at 95% confidence level). Most obvious changes were observed for the eastern and southeastern parts. Under future climate conditions periods with severe/danger heatstress events will increase further as compared with the historical period by 5–22% depending on the GCM used. Moreover, the average length of periods with severe/danger heatstress is expected to increase from ~ 3 days in the historical period to ~ 4–7 days by 2021–2050 and even to up to 10 days by 2071–2100. Based on the average results of three GCMs, by 2071–2100, around 22% of dairycattle population currently living in this area is expected to experience around 70 days more of severe/danger heatstress (compare with the historical period), especially in the southern half of WestAfrica. The result is alarming, as it shows that dairyproduction systems in WestAfrica are jeopardized at large scale by climate change and that depending on the GCM used, milk production might decrease by 200–400 kg/year by 2071–2100 in around 1, 7, or 11%. Our study calls for the development of improved dairycattleproduction systems with higher adaptive capacity in order to deal with expected futureheatstress conditions.
Environmental factors, particularly heatstress, present challenges to dairy cow productivity and health. In the absence of active cooling, exposure to elevated temperatures and humidity significantly reduce dry matter intake during lactation, and subsequent declines in milk yield can approach 25% depending on the severity and duration of the heatstress (reviewed by West, 2003). Lactating cows make metabolic adaptations which repartition additional energy away from productive purposes such that the actual decline in production exceeds what would be expected based on the lower DMI (Rhoads et al., 2009). Similarly, when dry cows are exposed to heatstress they produce less milk than cooled dry cows in the next lactation, even when both groups are cooled after calving (reviewed in Tao and Dahl, 2013). Dry cows under heatstress consume less feed than cooled cows, but the metabolic adaptations observed in lactating cows are not present (Tao et al., 2012). Despite the significant losses associated with productivity under heatstress, additional negative impacts on the overall health of lactating and dry cows and their calves accrue with exposure to high temperatures and humidity, and those outcomes are the focus of this paper.
Dairy farming is one the most important sectors of United Kingdom (UK) agriculture. It faces major challenges due to climate change, which will have direct impacts on dairy cows as a result of heatstress. In the absence of adaptations, this could potentially lead to consider- able milk loss. Using an 11-member climate projection ensemble, as well as an ensemble of 18 milk loss estimation methods, temporal changes in milk production of UK dairy cows were estimated for the 21st century at a 25 km resolution in a spatially-explicit way. While increases in UK temperatures are projected to lead to relatively low average annual milk losses, even for southern UK regions (<180 kg/cow), the ‘hottest’ 25×25 km grid cell in the hottest year in the 2090s, showed an annual milk loss exceeding 1300 kg/cow. This figure represents approximately 17% of the potential milk production of today’s average cow. Despite the potential considerable inter-annual variability of annual milk loss, as well as the large differences between the climate projections, the variety of calculation methods is likely to introduce even greater uncertainty into milk loss estimations. To address this issue, a novel, more biologically-appropriate mechanism of estimating milk loss is proposed that pro- vides more realistic future projections. We conclude that South West England is the region most vulnerable to climate change economically, because it is characterised by a high dairy herd density and therefore potentially high heatstress-related milk loss. In the absence of mitigation measures, estimated heatstress-related annual income loss for this region by the end of this century may reach £13.4M in average years and £33.8M in extreme years. a1111111111
There is a general consensus that the heritability for fertility traits is low, with most heritability estimates of traditional measures of fertility being <5% (Pryce and Veerkamp 2001; Wall et al. 2003; Jamrozik et al. 2005); heritability estimates for fertility traits derived using hormonal assays tend to be greater (Royal et al. 2002; Veerkamp, Koenen and de Jong 2001; Berry et al. 2012). To-date however, with the exception of a few studies (Grosshans et al. 1997; Pryce and Harris 2006; Olori, Meuwissen and Veerkamp 2002; Haile- Mariam, Morton and Goddard 2003), most of the reported genetic parameters for fer- tility traits have been estimated from ani- mals in year-round calving milk production systems. Firstly, traits different to those previously evaluated in year-round calving systems may be more pertinent to seasonal calving production systems such as the ability to calve early in the calving season. Secondly, the phenotypic and genetic vari- ation (and potentially their ratio) in some traits may differ with production system; for example in a seasonal calving herd strong emphasis is placed on the ability of the cow to return to service early post- calving while extended voluntary waiting periods may be tolerated in non-seasonal herds. Finally, covariances among fertility traits and between fertility traits and milk
Lameness is defined as any abnormality that causes the animal to change its gait or posture. Huxley (2013) reported that lameness is a symptom of a wide range of diseases. The primary cause of lameness in most dairy herds are hoof lesions (Oberbauer et al., 2013). Hoof lesions such as infectious hoof lesions (e.g. digital and interdigital dermatitis, and foot rot), horn lesions (e.g. sole hemorrhage, sole and toe ulcer, and white line disease), and other lesions (e.g. korn, fissures, thin soles, and corkscrew claw) are the major hoof lesions that causes lameness (Chapinal et al., 2013). In commercial dairy operations, lameness causes major economic losses due to its unfavorable effect on productivity and profitability of dairy industry. Several studies have reported how lameness causes weight loss and (Enting et al., 1997), reduced milk yield (Lucey et al., 1986; Warnick et al., 2001; Hernandez et al., 2005), reduced reproductive efficiency (Bicalho and Oikonomou, 2013), and premature culling (Booth et al., 2004). Lameness causes pain leading to a debilitating condition and distress in affected cows, which is considered as a serious animal welfare issue (Booth et al., 2004; Vermunt, 2007; Von Keyserlingk et al., 2009). Kelton et al. (1998) reported that lameness costs $302 per case. Guard (1999) estimated direct cost due to lameness in 100-cow herds to be $7,600. Cha et al. (2010) used a dynamic programming method and determined
gy input to excrement. One of the arguments of Cederberg & Stadig (2003) to system expan- sion was the high replacement rate (37% or 72 kg boneless meat yield per cow and year) in dairy farms in Sweden. Kraatz (2009) included the energy demand for rearing heifers in the energy input of milk production. Furthermore, she discussed various possibilities on how to allocate the whole energy input to milk, meat, calf, and excrement production by using bio- logical and physical relations. The energy input for milk, meat and calves was allocated ac- cording to the energy demand of cattle for maintenance and lactation. The energy allocated for excrement was performed according to the substitution of manure with chemical fertilis- ers. She carried out these allocations under several variants and provided a discussion. The reason not to including the energy output from excrement in the allocations is the grazing of the cows direct on the farm which causes to neglect the excrement in both input and output sides by Refsgaard et al. (1998), Grönroos et al. (2006) and Thomassen et al. (2008). Beside the energy input sources considered in the investigations, allocation method, and also the milk yield and milk type should be considered for the comparison of different reports.
Technology of dairycattleproduction on Zeleno Polje, Belje d.d. farm
Summary: Most important branch of agriculture and livestock breeding in the world is cattle breeding. In the Republic of Croatia, cattle breeding is divided into three sectors: milk production, beef production and those two combined. In Croatia, simmental breed is the most popular, holding 74% of entire milk and meat production. For milk production, holstein breed is most commonly used, so this breed is usually called "milk factory". We classify cattle breeding into extensive and intensive breeding. Extensive breeding is based on producing certain amount of products, with large number of cattle, but with small numbers of products per stock. Intensive breeding is sustained with large quantity producing cattle, with maximum amount of work and money invested. That way maximum production per stock is achieved, and one of the examples for such production is Zeleno Polje farm. The farm is owned by Belje d.d. company, and it is registered as cattle breeding and milk producing farm, with main task of producing holstein friesian cattle breed, which is known for high quantity milk production. To ensure high quality and quantity production, cattle is placed in 9 production groups (introduction to lactation, 40L, 28L, 18L, drying, preparation, freezing, mastitis).
The success of the 1986 project resulted in the introduction of a dairy progeny testing scheme in 1987. The scheme was run for the Holstein and Jersey breeds. The objectives of the scheme were given as to breed cows that are of sound dairy confirmation and are high producers of good quality milk. Breeders, through their breed societies, nominated several young bulls for testing. The breed societies inspected the bulls to evaluate them for type. This information, together with pedigree information for production and linear traits was used by a Sire Evaluation Committee to select bulls to be tested. At the inception of the program, six Holstein bulls and one Jersey bull were tested each year in participating herds. The owners of these herds were contracted to offer 18 percent of their cows for mating to young bulls each year and to rear and record production to the end of their first lactation all the resulting heifer calves. It was expected that each bull would have 80 to 90 daughters with completed lactations, given the population size. Appropriate models (developed in 1986) were used to analyse the data to calculate proofs for both bulls and cows. The number of bulls to be selected out of those tested was not fixed, therefore the selection intensity was not predetermined. The first group of bulls tested was from embryos imported from the USA. They were genetically better than the bulls that were already available in Zimbabwe, so non were culled (a selection intensity of zero). The proportion of cows mated to test bulls was low (18 %) as farmers were not willing to risk high use of untested bulls. In addition, a lot of emphasis was placed on the accuracy of evaluation (bulls were expected to have 80 to 90 daughters). This all resulted in a small number of bulls being tested and the inability to cull any.
The experimental design is to arrange the collected raw data and put them into standard tables. It is so to make every of the tables comparable to each other as the raw samples from the farmers have different pattern of record. The selected samples are according to the month that the cattle calved until the day it dry, so that a trend per lactation can be noted. The lactation curve is then shown in graph. After that, the average yield of total milking cow for the particular farm is calculated to see the lactation trend of the farm. Then, ten cows from each farms act as replication are selected for the statistical analysis.
ROSSA & BAZZO (2009), studying an absorption chiller of 17 kW thermal capacity (three times bigger than B1 and B3) and driven by heat waste from a natural gas turbine, reported COP values between 0.25 and 0.31 for a cooling process. SILVA & MOREIRA (2008) simulated chillers fired by natural gas and landfill gas through EES software (Engineering Equation Solver), and observed COPs from 0.12 to 0.36, for equipment with cooling capacity between 18 and 70 kW. This way, the results obtained here for B1 and B3 in cooling system (from 0.15 to 0.24) seem to be satisfactory.
production. When the environmental temperature is above the body temperature, the cows countenance the risk of heatstress and milk production can be decreased by as much as 50% (Ben Salem and Bouraoui, 2009). The comfortable environmental temperature for dairycattle ranges between 5 to 25 0 C which is also known as the thermal comfort zone (McDowell, 1976). The objective of this study was to monitor the trend of daily milk yield as function of ambient temperature and relative humidity during the months of summer season (July- October) at BAU Dairy farm and to analyze the composition of summer milk produced by Holstein Friesian crossbred dairy cows.
Heatstress increased rectal temperatures, respiration rates, and plasma cortisol concentrations and decreased milk yield No discernible effects on immune function due to bST Heatstress reduced lymphocyte migration to udder Limitations: Very low cow numbers
Ayrshire cattle are reddish brown and white spotted. Its spots are kind of unusual, because they are usually jagged and small and scattered all over their body. They would normally have long, upright horns, but most are dehorned as calves. This means that their horns are removed when they are very young. The Ayrshire is named after the County Ayr in Scotland, where the breed was first developed.
Coccidiosis is frequently associated with stress factors, such as weaning, change in feed, crowding or other disease problems. In young animals, which are the most susceptible, it can be diagnosed as young as 18-21 days of age. The reason this disease often develops early in life is that the young dairy calves are confined in previously contaminated areas, i.e. hutches, calf stalls, etc., or they are housed in overcrowded conditions. Once a facility has become contaminated, it has the potential for a recurring problem. Animals that develop coccidiosis may show only minor signs, such as rough hair coat, low grade diarrhea and unthriftiness. In more severe cases, animals can have bloody diarrhea, dehydration, depression and may even die. Whether the disease is mild or severe, the infected animal will be depressed in its growth rate, have reduced feed consumption and decreased feed efficiency.(5) This leads to an inability of the animal to reach its full growth potential, which can result in economic losses for the producer. External Parasites
Increasing standards for health and welfare of livestock has led to considerable research activity into ways to monitor and measure a wide range of traits (e.g., associated with fertility, legs/feet, metabolism, udder, birth, feeding, behavior, milk composition, body composition) that can be used for management and genetic selection purposes, as well as parameters of public interest (Eggar-Danner et al., 2015). Bell and Wilson (2018) found that regional differences in longevity of cows exists within UK dairy herds, with cows having a shorter life (averaging 2.6 lactations) in the region with the highest milk yields and longest interval between calvings (associated with poor fertility), compared to other regions studied (about 2.8 lactations on average) with lower milk yields and calving intervals; the average number of lactations across the UK was still below three lactations when cows are expected to reach their mature and optimum level of productivity. Ultimately maintaining healthy animals will enhance production, particularly later in life from increased lifetime performance (Bell et al., 2015). Therefore, management and breeding policies should be directed toward not only increasing production but decreasing the causes of involuntary culling (fertility, lameness, and udder health) (Bell et al., 2010). Survival within a herd influences the number of replacement animals needed, which in turn influences the productivity and profitability of the herd, as at a high replacement rate the costs are high but at too low a rate the production, reproduction, or genetic improvement of the herd may be impaired (Hadley et al., 2006). In dairy cows, several countries around the world (France, Italy, Germany, Switzerland, Belgium, Australia, United States, UK, Nordic countries, Ireland, The Netherlands) now give fitness traits more emphasis and weighting in their total economic merit index for ranking cattle for genetic selection purposes (Eggar-Danner et al., 2015) and less weighting than other countries toward milk production traits (milk, fat, and protein yield) at <50% weighting in the index
The results of the measurements of the physiological parameters in the monitored cows show that the mean values obtained in the treatment group were lower than the corresponding ones of the control group. Specifically, the sprinkler system especially influenced the respiration rate that in the treatment group was 56.4 breath/min on average, a little higher than the upper limit of the ideal range of 26-50 breath/min (Merck Veterinary Manual, 2012a). This result is in according with Calegari et al. (2012) and indicated a more favourable condition for heat dissipation in the pen with the sprinkler system. On the contrary, in the control group, the mean value of the respiration rate was 70.1 breath/min on average, that is considerably higher than the ideal range.
Key Words: calcium, lipopolysaccharide, dairy cow, yeast Introduction
Periparturient dairy cows can experience a myriad of metabolic disorders, and transient hypocalcemia represents one of the most common. Subclinical hypocalcemia is purportedly a gateway to other disorders such as ketosis, mastitis, and metritis, all of which compromise profitability and increase culling risks (DeGaris and Lean, 2008; Goff, 2008). After parturition, the mammary gland has a large calcium (Ca) demand, and proper parathyroid hormone (PTH) and calcitonin action is required to maintain eucalcemia (Horst et al., 2005). However, the mammary gland’s Ca uptake is so acute and extensive that it exceeds the homeostatic strategies employed to replenish circulating Ca (Goff, 2008) and cows can either enter into clinical or subclinical hypocalcemia. Although not overtly pathological, subclinical hypocalcemia has been associated with decreased productivity and other economically important phenotypes later in lactation (Goff, 2008, 2014; Oetzel, 2013). Different prophylactic and therapeutic strategies for preventing post-calving hypocalcemia include: feeding pre-calving acidifying rations (-DCAD), low Ca-diets (Thilsing-Hansen et al., 2002) or Ca chelating compounds (Goff, 2008). These dietary strategies have markedly reduced clinical rates of “milk fever”, but periparturient subclinical hypocalcemia remains a common post-calving “pathology”. Consequently, orally bolusing Ca following parturition has become a common management tactic (Oetzel and Miller, 2012; Oetzel, 2013) and preferably proven over intravenous Ca administration (Wilms et al., 2019).
The main constraint to forage production is the scarcity of land. Usually farmers do not spare cultivable land for fodder production. In Bangladesh poor farmer does not provides the high quality forages especially green grass for feeding their ruminants and due to increasing the population number the cultivated and agricultural land is diminishing day by day. As a result the pasture land is not available and hence the farmers depend on the low quality forages especially agricultural by products such as cereal straws, sugar-cane top, bagasse, tree leaves, road side grasses and stover etc. For example in Bangladesh the total area for fodder is about 6,312 hectare, producing only about 47,000 metric tons of fodder crops whereas very little grain is available for feeding the animals in the country. It is estimated that about 0.19 million tons of grain are available for livestock feeding, contributing only about 15.7 % of the total amount of concentrate feed required for farm livestock in Bangladesh (Khan, and Chaudhry, 2012). Rice straw is low in protein, fat, minerals, vitamins and other nutrients. The productions are adversely affected when ruminants are reared with these poor quality forages like rice straw (Khan and Chaudhry, 2012). Feeding ruminants with rice straw only will cause live weight and health loss (Sarnklong et al., 2010). Khan and Chaudhry (2011) suggested that the selected forages can offer complementary properties for their use to formulate forage based balanced diets to optimize the degradability and utilization of LQF in ruminants.
Hoof care has a significant impact on a cow’s mobility and how well she milks. Proper foot care is important because infection resistance, mobility and conformation affect an animal’s production level and also performance at shows. To establish a foot-care program, you must determine when an animal’s hooves need to be trimmed. In pasture conditions, feet usually don’t need to be trimmed. However, with confined housing, such as tie-stall or free- stall barns, routine trimming of dairy animals’ feet becomes essential. Until you are familiar with the procedures and skills necessary to trim the hooves yourself, it is recommended that you hire a