scholarly journals Non-additive QTL mapping of lactation traits in 124,000 sequence-imputed cattle reveals novel recessive loci

2021 ◽  
Author(s):  
Edwardo GM Reynolds ◽  
Thomas J Lopdell ◽  
Yu Wang ◽  
Kathryn Tiplady ◽  
Chad Harland ◽  
...  

Deleterious recessive conditions have primarily been studied in a Mendelian disease context. Recently, several large effect, deleterious recessive mutations were discovered via non-additive GWAS of quantitative growth and developmental traits in cattle. This showed quantitative traits can be used as proxies of genetic disorders if they are indicative of whole animal health status and susceptible to underlying genetic conditions. Lactation traits might also reflect genetic disorders in cattle, given the increased energy demands of lactation and the substantial stresses imposed on the animal. Here, we report a screen of over 124,000 cows for recessive effects based on lactation traits. We discovered novel loci associated with five large recessive impacts on milk yield traits represented by missense variants (DOCK8, IL4R, KIAA0556, and SLC25A4) or premature stop variants (ITGAL, LRCH4, and RBM34) as candidate causal mutations. On milk composition traits, we identified several small effect dominance contributions to previously reported additive QTL. In contrasting analyses of milk yield and milk composition phenotypes, we note differing genetic architectures. Milk yield phenotypes presented lower heritabilities and fewer additive QTL, but higher non-additive genetic variance and a higher proportion of loci exhibiting dominance compared to milk composition phenotypes. Large-effect recessive QTL are segregating at surprisingly high frequencies in cattle. We speculate that the differences in genetic architecture between milk yield and milk composition phenotypes derive from underlying dissimilarities in the cellular and molecular representation of these traits. Lactation yields may act as a better proxy than milk composition traits for a wide range of underlying biological disorders affecting animal fitness

2000 ◽  
Vol 25 ◽  
pp. 119-123
Author(s):  
T.W.J. Keady ◽  
C.S. Mayne ◽  
D.A. Fitzpatrick

AbstractTwo partially balanced change-over design experiments were undertaken to examine the effects of concentrate energy source on milk yield and composition of lactating diary cows offered a diverse range of grass silages. A total of nine silages differing in fermentation digestibility and intake characteristics were produced in experiments 1 and 2. Silage dry matter (DM) concentration ranged from 170 to 473 g/kg, ammonia nitrogen ranged from 58 to 356 g/kg nitrogen, digestible organic matter in the DM ranged from 551 to 724 g/kg and silage DM intake potential ranged from 57 to 103.8 g/kg w0.75 respectively. In experiment 1, 5 concentrates were formulated to contain similar concentrations of crude protein (CP), effective rumen degradable protein (ERDP), metabolizable energy (ME) and digestible undegradable protein (DUP) while three concentrates were formulated in experiment 2 to contain similar concentrations of CP, ME and DUP. The concentrates were prepared using barley, wheat, sugar beet pulp and citrus pulp as energy sources and formulated to achieve a wide range of starch concentrations. Starch concentrations ranged from 50 to 384 g/kg DM and 22 to 273 g/kg DM in experiments 1 and 2 respectively. There were no concentrate energy source by silage type interactions for silage intake, milk yield and composition. It is concluded that increasing starch intake resulted in positive and negative linear relationships for milk protein (P<0.001, R2 = 0.96) and fat (P<0.001, R2 = 0.85) concentrations respectively. Concentrate energy source had no effect on silage DM intake or milk yield.


2019 ◽  
Vol 56 (03) ◽  
pp. 743-746
Author(s):  
Adnan Mobeen

The present study was planned to cope with feed scarcity issue using bypass fat as a non-conventional feed resource. Twentyfour early lactating indigenous dairy animals comprising of twelve Nili-Ravi buffaloes and twelve Sahiwal cows were selected to determine the effect of bypass fat supplementation on daily milk yield, milk composition and change in body weight. These animals were randomly distributed in to four groups (G0, G1, G2 andG3) having similar parity and milk yield. All the experimental animals were fed with basal ration (Trifolium alexendrinum + wheat straw) and concentrate in equal proportion (3kg day-1 animal-1 ) in addition to 0, 250, 350 and 450g bypass fat animal-1day-1 , respectively. Data collected for each treatment was analyzed under completely randomized design using MINITAB (2000) and the mean was compared using the Tukey’s test (P<0.05). The data revealed a significant effect (P<0.05) on milk production and 3.14 kg day-1 more milk was produced in group G2 compared to control group. Fat corrected milk yield was also enhanced (P<0.05) from 8.25 (G0) to 12.36 kg day-1 (G2). Milk composition in the sense of fat percentage was also improved [5.25 (G0) to 5.78 (G2)] significantly. While average protein content, SNF% and total solids% remained unaffected. Similarly, change in body weight was non-significant. Milk value (Rs./day) was significantly (P<0.05) increased from 512.25 to 747.75 in the group G0 to G2. Form present finding it could be concluded that dietary supplementation of bypass fat in indigenous dairy animals is a better option to increase the milk yield without compromising milk quality and animal health


2019 ◽  
Vol 15 (02) ◽  
pp. 39-41
Author(s):  
H H Panchasara ◽  
A B Chaudhari ◽  
D A Patel ◽  
Y M Gami ◽  
M P Patel

The study was conducted to evaluate the effect of feeding herbal galactogogue preparation (Sanjivani biokseera) on the milk yield and milk constituents in lactating Kankrej cows. Thirty-two lactating Kankrej cows in their 1st to 6th lactation were taken for the experiment from 3 days after calving up to 52 days postpartum. All the animals were fed as per the standard seasonally available roughages and concentrates to meet their nutritional requirements. The cows were randomly divided into two uniform groups of 16 cows in each according to initial milk yield and milk composition. The animals in group-I were not given any supplement and served as control. The animals in group-II were given Sanjivani biokseera (Naturewell Industries) @ 60 g per day for 1-month, commencing 3 days after calving, in addition to the usual feeds/fodders. A clear difference was observed in milk yield from day 8 onward of experiment between groups with significant (plessthan0 0.05) higher values from day 16-52 in cows fed herbal galactogogue as compared to control, but no such distinct effect on milk constituents was observed on day 52 when analyzed. The use of herbal galactogogue significantly (p lessthan 0.05) increased the overall average of 52 days milk production, which was 9.34 ± 0.21 lit/day in supplemented as compared to 7.75 ± 0.26 lit/day in control animals. It was concluded that herbal galactogogue (Sanjivani biokseera) could increase milk yield in lactating dairy cows through its galactopoetic property and improved rumen environment.


Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 309
Author(s):  
Deise Aline Knob ◽  
André Thaler Neto ◽  
Helen Schweizer ◽  
Anna C. Weigand ◽  
Roberto Kappes ◽  
...  

Crossbreeding in dairy cattle has been used to improve functional traits, milk composition, and efficiency of Holstein herds. The objective of the study was to compare indicators of the metabolic energy balance, nonesterified fatty acids (NEFA), beta-hydroxybutyrate (BHBA), glucose, body condition score (BCS) back fat thickness (BFT), as well as milk yield and milk composition of Holstein and Simmental cows, and their crosses from the prepartum period until the 100th day of lactation at the Livestock Center of the Ludwig Maximilians University (Munich, Germany). In total, 164 cows formed five genetic groups according to their theoretic proportion of Holstein and Simmental genes as follows: Holstein (100% Holstein; n = 9), R1-Hol (51–99% Holstein; n = 30), first generation (F1) crossbreds (50% Holstein, 50% Simmental; n = 17), R1-Sim (1–49% Holstein; n = 81) and Simmental (100% Simmental; n = 27). The study took place between April 2018 and August 2019. BCS, BFT blood parameters, such as BHBA, glucose, and NEFA were recorded weekly. A mixed model analysis with fixed effects breed, week (relative to calving), the interaction of breed and week, parity, calving year, calving season, milking season, and the repeated measure effect of cow was used. BCS increased with the Simmental proportion. All genetic groups lost BCS and BFT after calving. Simmental cows showed lower NEFA values. BHBA and glucose did not differ among genetic groups, but they differed depending on the week relative to calving. Simmental and R1-Sim cows showed a smaller effect than the other genetic groups regarding changes in body weight, BCS, or back fat thickness after a period of a negative energy balance after calving. There was no significant difference for milk yield among genetic groups, although Simmental cows showed a lower milk yield after the third week after calving. Generally, Simmental and R1-Simmental cows seemed to deal better with a negative energy balance after calving than purebred Holstein and the other crossbred lines. Based on a positive heterosis effect of 10.06% for energy corrected milk (ECM), the F1, however, was the most efficient crossbred line.


animal ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 100015
Author(s):  
T.V.C. Nascimento ◽  
R.L. Oliveira ◽  
D.R. Menezes ◽  
A.R.F. de Lucena ◽  
M.A.Á. Queiroz ◽  
...  

1976 ◽  
Vol 56 (2) ◽  
pp. 233-242 ◽  
Author(s):  
L. J. FISHER ◽  
DOROTHY S. WALSH

Sixteen lactating Holstein cows were randomly assigned to treatment sequences in a 4 × 4 changeover experiment. Experimental periods were 28 days in length separated by 7 days for changeover. Cows were fed corn silage free choice and gradually increasing amounts of one of four dairy concentrates containing 0, 11, 22, or 34% rapeseed meal (RSM) of a Canadian, experimental, low glucosinolate–low erucic acid variety. Concentrate intake (kg dry matter/day), milk yield (kg/day) and body weight change (kg/28 days) were 8.45a, 8.71a, 8.37a and 7.17b; 24.40a, 24.03ab, 22.92bc and 21.96c and 7.6b, 22.4b, 13.0ab, and 3.0b for 0, 11, 22 and 34% RSM mixtures, respectively. There was no influence of treatment on milk composition. Ration dry matter (DM) and nitrogen digestibilities declined (P < 0.05) as the RSM in the concentrate mixture increased. The amount of nitrogen excreted in the urine was greatest for cows fed 0% RSM and least for cows fed 34% RSM. Cows fed concentrate mixtures containing 34% RSM had a lower blood thyroxine level than others (P < 0.05), but RSM-containing concentrates had no apparent effect on the conversion of thyroxine to triiodothyronine. Results of the trial indicated that this experimental variety of RSM had no detrimental effect on concentrate intake, DM digestibility, milk composition or thyroid hormone metabolism when included at levels up to 22% in the concentrate mixture. However, milk yield and apparent digestibility of ration nitrogen were decreased (P < 0.05) by the 22% RSM mixture. It was not certain from the current findings whether the depression in digestibility was due largely to the high oil content of the meal or due to the higher fiber content of the RSM-supplemented rations.


1969 ◽  
Vol 43 (4) ◽  
pp. 651-662 ◽  
Author(s):  
A. T. COWIE ◽  
P. E. HARTMANN ◽  
A. TURVEY

SUMMARY Twenty-one rabbits were hypophysectomized during the second week of lactation. Hypophysectomy inhibited milk secretion within 3–7 days. Restoration of the milk yield to pre-operative levels was obtained when daily injections of either sheep prolactin (50 or 100 i.u.) or human growth hormone (HGH) (2·5 or 5 mg.) were administered; partial recovery of the milk yield was obtained with 25 i.u. sheep prolactin/day or 1·25 mg. HGH/day. Neither bovine growth hormone (BGH), adrenocorticotrophin (ACTH) nor cortisol acetate had any significant restorative effects on milk secretion or synergistic effects when combined with sheep prolactin or HGH. The probable development of immune responses to sheep prolactin and HGH was observed. After hypophysectomy, changes in milk composition were found which were similar in trend to the more gradual normal changes observed in late lactation. Sheep prolactin and HGH restored the composition of the milk as well as the yields to normal levels, and both hormones caused rapid increases in lactose yields. The pigeon crop-stimulating potency of the HGH preparation was low (equivalent to 3·7 i.u. sheep prolactin/mg.), yet its lactogenic and galactopoietic potencies were high thus emphasizing the unreliability of assessing the mammotrophic potencies of HGH preparations in birds.


Author(s):  
Branislav Ftorek ◽  
Milan Saga ◽  
Pavol Orsansky ◽  
Jan Vittek ◽  
Peter Butko

Purpose The main purpose of this paper is to evaluate the two energy saving position control strategies for AC drives valid for a wide range of boundary conditions including an analysis of their energy expenses. Design/methodology/approach For energy demands analysis, the optimal energy control based on mechanical and electrical losses minimization is compared with the near-optimal one based on symmetrical trapezoidal speed profile. Both control strategies respect prescribed maneuver time and define acceleration profile for preplanned rest-to-rest maneuver. Findings Presented simulations confirm lower total energy expenditures of energy optimal control if compared with near-optimal one, but the differences are only small due to the fact that two energy saving strategies are compared. Research limitations/implications Developed overall control system consisting of energy saving profile generator, pre-compensator and position control system respecting principles of field-oriented control is capable to track precomputed state variables precisely. Practical implications Energy demands of both control strategies are verified and compared to simulations and preliminary experiments. The possibilities of energy savings were confirmed for both control strategies. Originality/value Experimental verification of designed control structure is sufficiently promising and confirmed assumed energy savings.


2016 ◽  
Vol 19 (1-2) ◽  
pp. 50-65
Author(s):  
MA Baset ◽  
KS Huque ◽  
NR Sarker ◽  
MM Hossain ◽  
MN Islam

A total of 160 cows, 10 cows in each of native (local cow) and crossbred (local × Holstein Friesian) origins differing in lactation were used in 2×2×2×2 factorial experiment using Randomized Block Design (RBD) to evaluate milk yield and composition of cows considering regions (good & poor feed base region), seasons (dry: Nov.–Feb. 2009 & wet: Jun.–Oct. 2009), genotypes and lactation. A “good and/or poor feed base” region was classified based on the availability of quantity and quality roughages throughout the year. The study revealed that the daily milk yield and 4% FCM of cows under good feed base condition were 6.76 and 6.49 kg, respectively and under poor feed base condition were 3.67 and 3.31 kg, respectively. Feed base region did not affect on milk fat and it was observed that the milk protein, lactose, solids-not-fat (SNF), minerals and total solids under good feed base condition were 37.9, 54.9, 100.9, 6.3 and 140.6 g/kg, respectively, whereas, under poor feed base condition the values were 36.3, 52.9, 98.0, 6.1 and 135.2 g/kg, respectively. Season did not affect milk yield and composition except minerals (6.5 g/kg vs. 5.9 g/kg). Genotypes significantly (p?0.01) influenced daily milk yield, the milk protein and minerals. Lactation did not affect milk yield and the milk protein, but influenced the fat, lactose, SNF, minerals and total solids. The interaction of feed base regions and seasons significantly (p?0.01) influenced milk yield and the milk fat and SNF. The milk protein and lactose was influenced by the interaction of feed bases region, seasons and lactation. Milk yield negatively correlated with fat per cent. The percentage of fat significantly (p?0.01) correlated with protein, lactose, SNF, and minerals %. The percentage protein correlated with lactose, SNF and minerals. Lactose % significantly (p?0.01) correlated with SNF%. It may be concluded that milk yield and composition depends on feed base region, genotype and lactation of cows. Season did not influence milk yield and the composition. Milk yield negatively correlated with the percentage of fat, protein, lactose, SNF and milk composition strongly correlated with each other.Bangladesh J. of Livestock Res. 19(1-2): 50-65, Jan-Dec 2012


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