Factors affecting the yield and quality of milk: I. The age of the cow

1929 ◽  
Vol 19 (2) ◽  
pp. 342-372 ◽  
Author(s):  
R. R. Kay ◽  
Andrew C. M'Candlish

1. The variations in production due to age have been investigated with the records of 738 Ayrshire cows for 4380 lactations.2. Milk and butterfat production increase up to about 7 years of age and then show a decrease.3. The fat percentage for 3-year-olds is higher than that for older cows.4. After 3 years of age there is little change in the fat percentage with age that is of any practical significance until advanced ages are reached, when there may be a fall of importance.5. The increase in production associated with age is probably attributable, in part, to the growth of the secretory tissue of the udder and to body growth in general.6. Part of the increase may also be due to an improvement in functional activity through use.7. The tendency for milk to show a slightly lower fat percentage as the cow advances in age is probably due to the fact that as the milk yield changes the fat yield changes in the same direction but at a slower rate.8. There is little known regarding the influence of very advanced age on production, but it is probable that many cows maintain for a long time the production associated with maturity, and then decline slowly.9. Heifers with a low fat percentage need not as a rule be expected to test higher on reaching maturity.10. It is probable that the increase in production with maturity is associated more closely with high initial production than with persistency of production.11. Correction factors for age are presented.

1930 ◽  
Vol 20 (1) ◽  
pp. 45-52 ◽  
Author(s):  
J. Glen ◽  
Andrew C. M'Candlish

1. Milk and butterfat production rise to about the sixth lactation, but beyond the fifth lactation the increase may be neglected.2. The lactation of maximum production may be taken as the fifth which corresponds to 7 years of age.3. Beyond the fifth lactation the milk and butterfat yields vary irregularly but show a downward tendency.4. The fat yield shows either a fall or only a very small increase in the second lactation.5. The fat percentage is highest in the first lactation, drops markedly in the second, remains fairly steady for a few lactations, though with a slight downward tendency, and then falls off in the higher lactations.6. Results obtained by applying correction factors for either age or lactation are quite comparable and choice in the method to be used will depend largely on the original data available.


2017 ◽  
Vol 42 (1) ◽  
pp. 48
Author(s):  
M. Mukson ◽  
H. Setiyawan ◽  
M. Handayani ◽  
A. Setiadi

The objectives of this research wereto analyze the local resource-based development of dairy cattle in orderto improve the production and quality of milk in Central Java. The research wascarried out by survey method. The research locations (Boyolali and Semarang) were chosen using purposive sampling method.In each regency was determined 2 sub district locations in which having the largest dairy cow population and 3 Dairy Cattle Farmer Associations (DCFA) in every sub district.Dairy farmers were sampled randomly, 10 farmers in every DCFA. Therefore, there were 120 dairy cattle farmers for sample. Data wereanalyzed using descriptive methods, location quotient (LQ) analysis and multiple linear regression statistical model. The dependent variables were yield and quality of milk (Y1,2) and the independent variables were human resources (x1), environmental resources (x2), capital resources (x3), entrepreneurship resources (x4), technology resources (x5), institution resources (x6) and infrastructure resources (x7). The LQ analysis showed that dairy cattle population, availability of forage and agricultural waste, and absorption of labour were very potential (LQ>1). Local resources significantly affected (P<0.01) the production and quality of dairy cattle milk. These results suggest that the development of dairy cattle business needs to consider the potential of local resources in order to improve the production and quality of milk.


1927 ◽  
Vol 17 (1) ◽  
pp. 118-139 ◽  
Author(s):  
T. J. Drakeley ◽  
Margaret K. White

The principal factors influencing the yield and quality of milk are (1) stage of the lactation period, (2) breed of the cow, (3) interval between milkings, (4) age of the cow, (5) individuality of the cow, (6) efficiency of the milker, (7) temperature and weather conditions, (8) health of the cow, (9) feeding.


1977 ◽  
Vol 17 (88) ◽  
pp. 765 ◽  
Author(s):  
AP Meissner ◽  
AL Clarke

Trials lasting three years were conducted at 27 sites in the south-east of South Australia to examine the responses of mown subterranean clover-ryegrass pastures to repeated annual applications of potassium chloride. At 20 sites, yield of dry matter (DM) was increased by potassium in one or more harvests. Responses were measured in 9 out of 55 winter harvests and 42 out of 86 spring harvests; mean responses to 100 kg ha-1 KCl (-Y100) at responsive sites were 380 and 560 kg DM ha-1 in winter and spring respectively. When potassium dressing increased yield, the proportion of clover in the sward was either maintained or increased. The herbage concentration of potassium was usually increased, and its magnesium concentration sometimes depressed, by potassium application. Although the K:Mg ratio was thereby increased, especially during winter, it rarely reached 15, the value considered necessary to induce grass tetany in cattle. Multivariate regression analysis showed that the exchangeable potassium concentration (Kex) of the top 10 cm of soil, the depth of soil overlying clay or limestone, and the sand content of the topsoil were factors affecting yield response. The best regression equations, however, explained less than half of the response variations. In practice, Kex alone would have usefully diagnosed potassium responsive sites. Responses occurred often when Kexwas less than 0.2 me 100 g-1 and rarely when it was greater. The use of potassium fertilizer is likely to be worthwhile to establish new pasture, to maintain the clover content of old pasture, and to increase the yield and quality of hay, where soils have less than 0.20 me 100 g-1 Kex. Such soils are most commonly sands more than 30 cm deep.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Jianbing Hu ◽  
Qiang Xu ◽  
Chenchen Liu ◽  
Binghao Liu ◽  
Chongling Deng ◽  
...  

AbstractSelf-incompatibility (SI) substantially restricts the yield and quality of citrus. Therefore, breeding and analyzing self-compatible germplasm is of great theoretical and practical significance for citrus. Here, we focus on the mechanism of a self-compatibility mutation in ‘Guiyou No. 1’ pummelo (Citrus maxima), which is a spontaneous mutant of ‘Shatian’ pummelo (Citrus maxima, self-incompatibility). The rate of fruit set and the growth of pollen tubes in the pistil confirmed that a spontaneous mutation in the pistil is responsible for the self-compatibility of ‘Guiyou No. 1’. Segregation ratios of the S genotype in F1 progeny, expression analysis, and western blotting validated that the reduced levels of S2-RNase mRNA contribute to the loss of SI in ‘Guiyou No. 1’. Furthermore, we report a phased assembly of the ‘Guiyou No. 1’ pummelo genome and obtained two complete and well-annotated S haplotypes. Coupled with an analysis of SV variations, methylation levels, and gene expression, we identified a candidate gene (CgHB40), that may influence the regulation of the S2-RNase promoter. Our data provide evidence that a mutation that affects the pistil led to the loss of SI in ‘Guiyou No. 1’ by influencing a poorly understood mechanism that affects transcriptional regulation. This work significantly advances our understanding of the genetic basis of the SI system in citrus and provides information on the regulation of S-RNase genes.


Foods ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 424 ◽  
Author(s):  
Ahmad ◽  
Cawood ◽  
Iqbal ◽  
Ariño ◽  
Batool ◽  
...  

Carrots are a multi-nutritional food source. They are an important root vegetable, rich in natural bioactive compounds, which are recognised for their nutraceutical effects and health benefits. This review summarises the occurrence, biosynthesis, factors affecting concentration, and health benefits of phytochemicals found in Daucus carota. Two hundred and fifty-five articles including original research papers, books, and book chapters were analysed, of which one hundred and thirty articles (most relevant to the topic) were selected for writing the review article. The four types of phytochemicals found in carrots, namely phenolics, carotenoids, polyacetylenes, and ascorbic acid, were summarised. These chemicals aid in the risk reduction of cancer and cardiovascular diseases due to their antioxidant, anti-inflammatory, plasma lipid modification, and anti-tumour properties. Numerous factors influence the amount and type of phytochemicals present in carrots. Genotype (colour differences) plays an important role; high contents of α and β-carotene are present in orange carrots, lutein in yellow carrots, lycopene in red carrots, anthocyanins in the root of purple carrots, and phenolic compounds abound in black carrots. Carotenoids range between 3.2 mg/kg and 170 mg/kg, while vitamin C varies from 21 mg/kg to 775 mg/kg between cultivars. Growth temperatures of carrots influence the level of the sugars, carotenoids, and volatile compounds, so that growing in cool conditions results in a higher yield and quality of carrots, while higher temperatures would increase terpene synthesis, resulting in carrots with a bitter taste. It is worthwhile to investigate the cultivation of different genotypes under various environmental conditions to increase levels of phytochemicals and enhance the nutritional value of carrot, along with the valorisation of carrot by-products.


2020 ◽  
Vol 5 (86) ◽  
pp. 3-10
Author(s):  
V.G. Chernikov ◽  
◽  
R.A. Rostovtsev ◽  
N.A. Kudryavtsev ◽  
I.V. Uschapovsky ◽  
...  

The formation of fiber flax yield and quality parameters depends on many soil-climatic, breedinggenetic, as well as anthropogenic factors. The quality of flax fiber is a combination of a number of features and properties that depend on the varietal characteristics of plants, the conditions of their cultivation, technologies for harvesting and straw retting, as well as on the processing modes of raw materials. During plant vegetation (90-130 days) many factors such as soil conditions (pH 4.8-5.5, humus 1.8-2.5%, P2O5 and K2O – 150-200 and 100-200 mg/kg, respectively) and the area of plant nutrition (15-30 million seeds/ha), temperature regime (the sum of active temperatures 1000-1800ºC), water supplying (400-430 units of water mass to create 1 unit of dry matter) and insolation (the arrival of FAR during the growing season 20-25 kcal / cm²), contamination of weeds (more than 60 annual and perennial species) and pests (more than 200 types of fungal, bacterial and viral diseases), features of phytosanitary measures (more than 50 chemicals) and agrotechnologic manners (Federal Register of technologies for the production of crop products) have a great influence on the quality of flax raw materials and can be a limit factor. Environmentally hazardous pollution of air, water and soil - the main components for the production of fiber flax – strongly affects the yield and quality of flax products. The development of waste-free environmentally friendly technologies for the cultivation, harvesting and processing of flax is an urgent task of scientific support of the industry. The main environmental factors affecting the yield and quality of fiber flax are discussed in the article.


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