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Each lactation begins with the birth of a calf, and the initial yield is a reliable indicator of the animal’s genetic potential. The highest yield is reached after five to six weeks of lactation and maintained for some weeks. Thereafter the yield decreases until the end of lactation. Lactation ends as the dry period starts.
In buffalo, the highest lactation milk yield is seen in the fourth lactation, after which it declines. The shape of the lactation curve depends on factors such as feed, management, milking frequency and diseases. The length of lactation and yield for various breeds is shown in Table 11. The optimum lactation length in Murrah buffalo has been reported to be 262 to 295 days.
In Italy it is recommended to keep a lactation length of 270 days in controlled herds. ICAR recommends a lactation length of 305 days, similar to that for controlled cattle.
Lactation and milk yield depend on both genetic and non-genetic factors. The genetic influence is from species, breed, and individual animals. Further, it is affected by the ability to reproduce – that is by fertility and the calving interval. Improvements in these factors may result from breeding and selection.
The non-genetic factors are management, amount and quality of feed, and the farmer’s skill in detecting heat and illnesses. Factors which are outside the farmer’s control such as climate, temperature and humidity also influence lactation and milk yield.
Buffalo in a field near Naples, Italy.
Feeding is the most important factor for increasing and sustaining the milk yield. Sufficient amounts of energy, protein, minerals and water must be provided in order to achieve maximum yield. See chapter 4 section on: Practical feeding of the lactating buffalo.
Calving interval is closely related to lactation length and milk yield. The longer the calving interval, the longer the lactation and the higher the lactation yield. However, total lifetime yield will be substantially less than that of a buffalo with shorter calving intervals. (See chapter 2 section on: Breeding buffalo).
Milking. The anatomy of the udder and physiology of milk ejection in buffalo is quite primitive compared to that of dairy cows (see chapter 5: Milking). When a buffalo is being machine milked for the first time it is important to ensure that the udder is emptied efficiently. Even in dairy cows it is known that milk ejection is inhibited or disturbed when they are milked in unfamiliar surroundings, and then it is only possible to extract the cisternal milk (Bruckmaier et al., 1993). Repeated occurrence of inhibition of milk ejection and high residual milk fractions could result in a reduction in the secretory activity in the mammary gland.
Reproductive efficiency. Studies on reproductive efficiency indicate that Riverine breeds of buffalo reach puberty around six months earlier than Swamp breeds. However pre-weaning and weaning nutrition is important in promoting growth and achieving puberty in all breeds: animals that have a higher daily gain reach puberty in a shorter time. Because of the weight differences between breeds, heifer weight at first conception can vary from 250 to 400kg. Heifers bred with a good early management system conceived at a younger age than a control group (Barile, 2005).
The weight of the heifer at calving seems to affect milk yield. Studies on Murrah (cited in Ståhl Högberg and Lind, 2003) indicate that buffalo heifers should weigh about 400 to 500 kg at the time of calving in order to reach maximum milk
production.
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Buffalo should be dried off approximately two to three months before expected calving. The dry period is valuable to the buffalo, she may rest and the udder tissue recuperates and reconstitutes itself.
In high yielding herds (above 10 kg per day on average) the buffalo should be dried off when the daily yield falls below 2.5 kg, even if it is still more than three months to expected calving. An alternative to drying off is to use the buffalo as a foster mother to newly born calves. One buffalo may serve one newborn calf, or two older calves which also receive additional feed. Care should be taken to dry the foster mother off completely no later than two months before calving.
In herds which are hand milked and where the yield is low, it is difficult to set a lower limit in kg. Instead, the two months limit is recommended.
Milk from buffalo differs from that from cattle. The biggest difference is with respect to fat. In cattle, the milk contains between 3 to 5% fat, depending on feed and breed. In buffalo milk the average fat content is usually 7 to 8% but may be as high as 13%.
Buffalo milk fat has a higher melting point than that of cattle, due to its higher proportion of saturated fatty acids (77:23, saturated:unsaturated). Buffalo milk fat contains higher proportions of butyric, palmitic and stearic acids and a lower content of caproic, caprylic, capric and lauric acids than does cow milk (Ganguli, 1974). Phospholipids and cholesterol are lower in buffalo milk. It is also less susceptible to oxidative changes compared to cows’ milk.
Fat in buffalo milk has characteristic differences from fat in cow’s milk. The fat globules in buffalo milk have an average diameter of 2.80 µm (Martini et al., 2003), smaller than those in cow milk, which have an average diameter of 3.0-5.0 µm (Alais, 1984). In buffalo milk 91% of fat globules range from 2.1 to 4.0 µm and the size is positively correlated to the proportion of unsaturated fatty acids (Martini et al., 2003).
The content of protein, lactose and ash is somewhat higher in buffalo milk than in cattle milk. Buffalo milk contains more Vitamin A than cow milk, and only traces of carotene. This makes the milk look very white, as opposed to cattle milk which has a slight yellow shade.
The different types of casein found in bovine milk are also found in buffalo milk, although in slightly different proportions.
When making a general comparison to cow milk it can be said that buffalo milk contains significantly more total solids, higher levels of the important minerals like calcium and phosphorus, substantially less cholesterol, more of the natural anti-oxidant tocopherol and more vitamin A.
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New born buffalo calves need colostrum
During approximately the first three days of lactation the buffalo secretes colostrum. Colostrum is vital for the newborn calf and its composition reflects the calf’s need. Colostrum contains the important proteins, the immunoglobulins, which are the newborn calf’s source of antibodies. The iron and copper content of colostrum is markedly higher than that in normal milk.
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There are several factors that influence the composition of milk within a species: primarily stage of lactation, milk yield, season, feeding, nutritional level and completeness of milking. Milk composition can be altered both before and after milking. If change occurs inside the udder it is mostly due to a disease or to treatment of the disease by antibiotics or another type of medication. Changes in feed can alter the composition of milk, but these changes are seldom extreme, usually falling within normal intervals. The season of the year can also affect milk composition, although these changes are mostly due to differences in feeding during different seasons.
A study on Nili-Ravi buffalo in Pakistan showed the influence on fat percentage of stage of lactation, with fat percentage increasing steadily from 5.5% in the first month of lactation to 7.5% in the tenth month of lactation. It was reported by Ganguli (1974) that the percentage of fat in buffalo milk varied from 6.37 to 8.10%, and protein from 3.78 to 4.65%.
In Brazil it has been reported that the percentage of fat in buffalo milk was around 5.95% and protein content around 4.2% (Tonhati and Cerón-Muñoz, 2002).In Italy it has been reported that there is an improvement in the percentages of fat (8.07%) and protein (4.69%). This improvement has been mainly attributed to selective breeding for higher fat and protein, and to improved feeding and nutrition (Italian Breeders’ Association A.I.A., 2005).
A rule of thumb is that roughage increases fat content in milk, whereas concentrate depresses it. This depends on the differences in production of volatile fatty acids (VFA) in the rumen from the different carbohydrate sources. Feed rich in fibre results in a higher proportion of acetic acid, increasing the fat content of the milk. Feed rich in concentrate results in a higher proportion of propionic acid which is unfavorable for milk fat synthesis. If too much concentrate is given, levels of milk fat may be reduced.
Higher energy diets seem to give better coagulation properties in the milk. Long-chain fatty acids increase when the energy concentration in feed is low.
Glucosinolates in Brassica spp. are hydrolyzed by the ruminal microbes into thiocyanates, iso-thiocyanates and some other products. Thiocyanate is then excreted in the milk. Extremely high feeding levels with Brassica spp. may lead to undesirable levels of thiocyanate in the milk. Thiocyanate may cause thyroid enlargement in animals as well as in the humans ingesting it. Common feedstuffs of Brassica spp. are mustard fodder and mustard oil cake. Even 15 days after withdrawal of mustard feed, circulatory high levels of thiocyanate may be secreted in the milk.
Mastitis changes the milk composition dramatically. If antibiotics are applied to cure mastitis, they will be excreted in the milk. Controlling external parasites with medication such as diazinon affects milk yield as well as composition. The chemical may be detected in the milk up to 48 hours after dermal application.
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