A study investigating the relationship between milk urea nitrogen and the reproductive performance of Holstein cows
Περίληψη
Since protein is a fundamental component of dairy cows' diet, as well as its metabolites, it is critical to pay attention to milk urea nitrogen (MUN) in order to control the protein concentration in diet because it is one of the most prevalent compounds in milk. Hence, the present research evaluated MUN and its relationship with some reproductive performances and fertility of Holstein dairy cows. There were four groups of data concerning the reproductive and productive performance of large herds of dairy cows in Iran, including group 1) milk urea nitrogen (MUN) less than 12.96 mg/dl; group 2) MUN between 12.96 and 14.35 mg/dl; group 3) MUN between 14.35 and 15.88 mg/dl; and group 4) MUN over 15.88 mg/dl. Initially, a list of each dairy herd involved in Iran's DHI program was prepared, and 30 dairy herds with an excess of 1000 lactating cows were randomly selected. In order to mix the data on reproduction and milk composition, FoxPro 2.6 software was used. A statistical analysis of milk urea nitrogen and other independent variables was conducted through analysis of variance. The aforementioned results regarding the importance of reproduction and pregnancy rate in lactating cows and determining the appropriate concentration of milk urea nitrogen indicate that this parameter could be optimally used to control the protein-to-energy ratio and protein consumption of lactating cows in their diet.
Λεπτομέρειες άρθρου
- Πώς να δημιουργήσετε Αναφορές
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Sadeghi, K., Ganjkhanlou, M., Fekri, A., & Palangi, V. (2025). A study investigating the relationship between milk urea nitrogen and the reproductive performance of Holstein cows. Περιοδικό της Ελληνικής Κτηνιατρικής Εταιρείας, 75(4), 8353–8362. https://doi.org/10.12681/jhvms.37076
- Τεύχος
- Τόμ. 75 Αρ. 4 (2024)
- Ενότητα
- Research Articles
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Αναφορές
Abdisa T (2018) Review on the reproductive health problem of dairy cattle.
Journal of Dairy & Veterinary sciences 5(1), 1-12.
Adamczyk K, Makulska J, Jagusiak W and Węglarz A (2017) Associations
between strain, herd size, age at first calving, culling reason and
lifetime performance characteristics in Holstein-Friesian cows. Animal,
(2), 327-334.
Ahammed R, Tasnim M, Halim MA, Sarkar M, Islam MS and Morshed
M (2018) A Comparative study on reproductive hormones of repeat
breeding and synchronized repeat breeding dairy cows under bathan
rearing system at Baghabari milk shed areas in Bangladesh. IOSR
Journal of Agriculture and Veterinary Science 11(11), 55-60.
Alabbasi HHH and Hatif SA (2019) The effect of date fruit on puberty
and sexual maturity in heifers. Kufa Journal for Agricultural Sciences
(2), 47-54.
Albarrán-Portillo B and Pollott GE (2013) The relationship between fertility
and lactation characteristics in Holstein cows on United Kingdom
commercial dairy farms. Journal of Dairy Science 96(1), 635-646.
Anand I, Dhaliwal GS and Chawla PS (2019) High blood/Milk urea nitrogen
had deleterious impact on fertility parameters in crossbred cows.
The Indian Journal of Animal Reproduction 40(1), 42-44.
Anderson GW and Barton BA (1988) Reproductive efficiency: potential
nutrition-management interactions. Proceedings of Winter Dairy
Management Schools, Cornell University, Ithaca, NY. USA, pp.107.
Arbel R, Bigun Y, Ezra E, Sturman H and Hojman D (2001) The effect of
extended calving intervals in high lactating cows on milk production
and profitability. Journal of Dairy Science 84(3), 600-608.
Arunvipas P, VanLeeuwen JA, Dohoo IR, Leger ER, Keefe GP, Burton
AS and Lissemore KD (2007) Milk urea-nitrogen negatively affected
first-service breeding success in commercial dairy cows in Prince Edward
Island, Canada. Preventive Veterinary Medicine 82(1-2), 42-50.
Ayaşan T, Hizli H, Yazgan E, (2011) The effect of milk urea nitrogen on
milk composition in Holstein dairy cows. Eurasian Journal of Veterinary
Sciences, 27 (4), 219-222.
Beatson PR, Meier S, Cullen NG and Eding H (2019) Genetic variation in
milk urea nitrogen concentration of dairy cattle and its implications
for reducing urinary nitrogen excretion. Animal 13(10), 2164-2171.
Bertipaglia ECA, Silva RG and Maia ASC (2018) Fertility and hair coat
characteristics of Holstein cows in a tropical environment. Animal
Reproduction 2(3), 187-194.
Birukawa N, Ando H, Goto M, Kanda N, Pastene LA, Nakatsuji H, Hata
H and Urano A (2005) Plasma and urine levels of electrolytes, urea
and steroid hormones involved in osmoregulation of cetaceans. Zoological
Science 22(11), 1245-1257.
Bisinotto RS, Greco LF, Ribeiro ES, Martinez N, Lima FS, Staples CR,
Thatcher WW and Santos JEP (2018) Influences of nutrition and metabolism
on fertility of dairy cows. Animal Reproduction 9(3), 260-
Bjelland DW, Weigel KA, Hoffman PC, Esser NM and Coblentz WK
(2011) The effect of feeding dairy heifers diets with and without supplemental
phosphorus on growth, reproductive efficiency, health, and
lactation performance. Journal of Dairy Science 94(12), 6233-6242.
Bjelland DW, Weigel KA, Vukasinovic N and Nkrumah JD (2013) Evaluation
of inbreeding depression in Holstein cattle using whole-genome
SNP markers and alternative measures of genomic inbreeding. Journal
of Dairy Science 96(7), 4697-4706.
Bobbo T, Penasa M, Rossoni A and Cassandro M (2020) Genetic aspects
of milk urea nitrogen and new indicators of nitrogen efficiency in
dairy cows. Journal of Dairy Science 103(10), 9207-9212.
Braga Paiano R, Becker Birgel D and Harry Birgel Junior E (2019) Uterine
involution and reproductive performance in dairy cows with metabolic
diseases. Animals 9(3), 93.
Broderick GA and Clayton MK (1997) A statistical evaluation of animal
and nutritional factors influencing concentrations of milk urea nitrogen.
Journal of Dairy Science 80(11), 2964-2971.
Bruckental I, Oldham JD and Sutton JD (1980) Glucose and urea kinetics
in cows in early lactation. British Journal of Nutrition 44(1), 33-45.
Burgos SA, Fadel JG and DePeters EJ (2007) Prediction of ammonia
emission from dairy cattle manure based on milk urea nitrogen: Relation
of milk urea nitrogen to urine urea nitrogen excretion. Journal of
Dairy Science 90(12), 5499-5508.
Butler WR (1998) Effect of protein nutrition on ovarian and uterine physiology
in dairy cattle. Journal of Dairy Science 81(9), 2533-2539.
Butler WR, Calaman JJ and Beam SW (1996) Plasma and milk urea nitrogen
in relation to pregnancy rate in lactating dairy cattle. Journal of
Animal Science 74(4), 858-865.
Canfield RW, Sniffen CJ and Butler WR (1990) Effects of excess degradable
protein on postpartum reproduction and energy balance in dairy
cattle. Journal of Dairy Science 73(9), 2342-2349.
Carlsson J and Pehrson B (1993) The relationships between seasonal variations
in the concentration of urea in bulk milk and the production
and fertility of dairy herds. Journal of Veterinary Medicine Series A
(1‐10), 205-212.
Carroll DJ, Barton BA, Anderson GW and Smith RD (1988) Influence of
protein intake and feeding strategy on reproductive performance of
dairy cows. Journal of Dairy Science 71(12), 3470-3481.
Cattáneo L, Signorini ML, Bertoli J, Bartolomé JA, Gareis NC, Díaz PU,
Bo GA and Ortega HH (2014) Epidemiological description of cystic
ovarian disease in argentine dairy herds: risk factors and effects on the
reproductive performance of lactating cows. Reproduction in Domestic
Animals 49(6), 1028-1033.
Cowley FC, Barber DG, Houlihan AV and Poppi DP (2015) Immediate
and residual effects of heat stress and restricted intake on milk protein
and casein composition and energy metabolism. Journal of Dairy Science
(4), 2356-2368.
Crowe MA, Hostens M and Opsomer G (2018) Reproductive management
in dairy cows-the future. Irish Veterinary Journal 71(1), 1-13.
Dallago GM, de Figueiredo DM, de Resende Andrade PC, dos Santos RA,
Lacroix R, Santschi DE and Lefebvre DM (2019) Predicting first test
day milk yield of dairy heifers. Computers and Electronics in Agriculture
(2), 105032.
Dash S, Chakravarty AK, Singh A, Upadhyay A, Singh M and Yousuf S
(2016) Effect of heat stress on reproductive performances of dairy
cattle and buffaloes: A review. Veterinary World 9(3), 235.
Devi P, Debbarma S, Kumar G and Thakur P (2019) Effect of heat stress
on reproduction in farm animals and its mitigation: A review. Journal
of Entomology and Zoology Studies 7(2), 342-345.
Doska MC, Silva DFFD, Horst JA, Valloto AA, Rossi Junior P and Almeida
RD (2012) Sources of variation in milk urea nitrogen in Paraná
dairy cows. Revista Brasileira de Zootecnia 41(3), 692-697.
Elrod CC and Butler WR (1993) Reduction of fertility and alteration of
uterine pH in heifers fed excess ruminally degradable protein. Journal
of Animal Science 71(3), 694-701.
Esposito G, Irons PC, Webb EC and Chapwanya A (2014) Interactions
between negative energy balance, metabolic diseases, uterine health
and immune response in transition dairy cows. Animal Reproduction
Science 144(3-4), 60-71.
Fahey J, Boland MP and O’Callaghan D (2001) The effects of dietary urea
on embryo development in superovulated donor ewes and on early
embryo survival and development in recipient ewes. Animal Science
(2), 395-400.
Ferguson JD, Blanchard TL and Chalupa W (1987) November. Protein,
fats and fertility in dairy cows. In American Association of Bovine
Practitioners Proceedings of the Annual Conference pp. 112-117.
Ferguson JD, Galligan DT, Blanchard T and Reeves M (1993) Serum urea
nitrogen and conception rate: the usefulness of test information. Journal
of Dairy Science 76(12), 3742-3746.
Gábor G, Tóth F, Ózsvári L, Abonyi‐Tóth Z and Sasser RG (2008) Factors
influencing pregnancy rate and late embryonic loss in dairy cattle.
Reproduction in Domestic Animals 43(1), 53-58.
Garcia-Bojalil CM, Staples CR, Thatcher WW and Drost M (1994) Protein
intake and development of ovarian follicles and embryos of superovulated
nonlactating dairy cows. Journal of Dairy Science 77(9), 2537-2548.
Gath VP, Crowe MA, O’Callaghan D, Boland MP, Duffy P, Lonergan P
and Mulligan FJ (2012) Effects of diet type on establishment of pregnancy
and embryo development in beef heifers. Animal Reproduction
Science 133(3-4), 139-145.
Gernand E, König S and Kipp C (2019) Influence of on-farm measurements
for heat stress indicators on dairy cow productivity, female fertility,
and health. Journal of Dairy Science 102(7), 6660-6671.
Godden SM, Lissemore KD, Kelton DF, Leslie KE, Walton JS and Lumsden
JH (2001) Relationships between milk urea concentrations and
nutritional management, production, and economic variables in Ontario
dairy herds. Journal of Dairy Science 84(5), 1128-1139.
Gonzalez-Recio O, Alenda R, Chang YM, Weigel KA and Gianola D
(2006) Selection for female fertility using censored fertility traits
and investigation of the relationship with milk production. Journal of
Dairy Science 89(11), 4438-4444.
Gross JJ, Kessler EC, Albrecht C and Bruckmaier RM (2015) Response of
the cholesterol metabolism to a negative energy balance in dairy cows
depends on the lactational stage. PloS One 10(6), 0121956.
Gunn PJ, Schoonmaker JP, Lemenager RP and Bridges GA (2014) Feeding
excess crude protein to gestating and lactating beef heifers: Impact
on parturition, milk composition, ovarian function, reproductive
efficiency and pre-weaning progeny growth. Livestock Science
(3), 435-448.
Gustafsson AH and Palmquist DL (1993) Diurnal variation of rumen
ammonia, serum urea, and milk urea in dairy cows at high and low
yields. Journal of Dairy Science 76(2), 475-484.
Hafez ESE and Hafez B (2013) Reproduction in farm animals. John Wiley
& Sons pp. 518-522.
Heins BJ and Hansen LB (2012) Fertility, somatic cell score, and production
of Normande× Holstein, Montbéliarde× Holstein, and Scandinavian
Red× Holstein crossbreds versus pure Holsteins during their first
lactations. Journal of Dairy Science 95(2), 918-924.
Heins BJ, Hansen LB and Seykora AJ (2006) Calving difficulty and
stillbirths of pure Holsteins versus crossbreds of Holstein with Normande,
Montbeliarde, and Scandinavian Red. Journal of Dairy Science
(7), 2805-2810.
Henao-Velásquez AF, Múnera-Bedoya OD, Herrera AC, Agudelo-Trujillo
JH and Cerón-Muñoz MF (2014) Lactose and milk urea nitrogen:
fluctuations during lactation in Holstein cows. Revista Brasileira de
Zootecnia 43(4), 479-484.
Hof G, Vervoorn MD, Lenaers PJ and Tamminga S (1997) Milk urea nitrogen
as a tool to monitor the protein nutrition of dairy cows. Journal
of Dairy Science 80(12), 3333-3340.
Hristova VK (2014) Study of Seasonal Dynamics of Blood Metabolic
Profile and Milk Urea Nitrogen (MUN) Level of Cows with Reproducti.
Accelerating the World’s Research 35(5), 36-54.
Ibtisham F, Nawab AAMIR, Li G, Xiao M, An L and Naseer G (2018)
Effect of nutrition on reproductive efficiency of dairy animals. Medycyna
Weterynaryjna 74(6), 356-361.
Jannah M, Mustofa I, Utama S, Mulyati S, Safitri E and Al-Arif MA
(2019) Identification of estrogen levels in dairy cows based on mun
levels and pregnancy rates. Indian Journal of Public Health Research
& Development 10(12), 320-324.
Jonker JS, Kohn RA and Erdman RA (1998) Using milk urea nitrogen to
predict nitrogen excretion and utilization efficiency in lactating dairy
cows. Journal of Dairy Science 81(10), 2681-2692.
Jordan ER and Swanson LV (1979) Serum progesterone and luteinizing
hormone in dairy cattle fed varying levels of crude protein. Journal of
Animal Science 48(5), 1154-1158.
Jordan ER, Chapman TE, Holtan DW and Swanson LV (1983) Relationship
of dietary crude protein to composition of uterine secretions and
blood in high-producing postpartum dairy cows. Journal of Dairy
Science 66(9), 1854-1862.
Kafilzadeh F and Farivar F (2006) Relationship between pregnancy and
blood or milk urea nitrogen in lactating dairy cows. Iranian Journal
of Agricultural Sciences 37(2), 353-360.
Kananub S, Pechkerd P, Van Leeuwen J, Stryhn H and Arunvipas P (2020)
Evaluation of influence of milk urea nitrogen on reproductive performance
in smallholder dairy farms. Australian Veterinary Journal
(8), 375-379.
Karapetkovska-Hristova V, Tomovska J, Bonev G, Dimitrov S, Dimitrovska
G, Presilski S and Ahmad MA (2014) Interrelationship
between the milk urea nitrogen level and milk coagulation traits in
Holstein-Friesian cows with reproductive disorders in R. Macedonia.
International Journal of Enhanced Research in Science Technology
& Engineering 3(4), 199-207.
Kohn RA, Kalscheur KF and Russek-Cohen E (2002) Evaluation of models
to estimate urinary nitrogen and expected milk urea nitrogen.
Journal of Dairy Science 85(1), 227-233.
Kume S, Numata K, Takeya Y, Miyagawa Y, Ikeda S, Kitagawa M, Nonaka
K, Oshita T and Kozakai T (2008) Evaluation of urinary nitrogen
excretion from plasma urea nitrogen in dry and lactating cows.
Asian-Australasian Journal of Animal Sciences 21(8), 1159-1163.
Larson SF, Butler WR and Currie WB (1997) Reduced fertility associated
with low progesterone postbreeding and increased milk urea nitrogen
in lactating cows. Journal of Dairy Science 80(7), 1288-1295.
Larson SF, Butler WR and Currie WB (2007) Pregnancy rates in lactating
dairy cattle following supplementation of progesterone after artificial
insemination. Animal Reproduction Science 102(1-2), 172-179.
Law RA, Young FJ, Patterson DC, Kilpatrick DJ, Wylie ARG and Mayne
CS (2009) Effect of dietary protein content on the fertility of dairy
cows during early and mid-lactation. Journal of Dairy Science 92(6),
-2746.
Li HQ, Liu Q, Wang C, Yang ZM, Guo G, Huo WJ, Pei CX, Zhang YL,
Zhang SL, Wang H and Liu JX (2016) Effects of dietary supplements
of rumen-protected folic acid on lactation performance, energy balance,
blood parameters and reproductive performance in dairy cows.
Animal Feed Science and Technology 213(6), 55-63.
Linn J (2006) Feed efficiency: Its economic impact in lactating dairy
cows. WCDS Advances in Dairy Technology 18(19-28), 30.
Liu J, Li L, Chen X, Lu Y and Wang D (2019) Effects of heat stress on
body temperature, milk production, and reproduction in dairy cows:
A novel idea for monitoring and evaluation of heat stress-A review.
Asian-Australasian Journal of Animal Sciences 32(9), 1332.
López-Gatius F (2018) Approaches to increase reproductive efficiency in
artificially inseminated dairy cows. Animal Reproduction 10(3), 143-
Maya-Soriano MJ, López-Gatius F, Andreu-Vázquez C and López-Béjar
M (2013) Bovine oocytes show a higher tolerance to heat shock in
the warm compared with the cold season of the year. Theriogenology
(2), 299-305.
Mekonnin A, Howie AF, Riley S, Gidey G, Tegegne DT, Desta G, Ashebir
G, Gebrekidan B and Harlow C (2017) Serum, milk, saliva and
urine progesterone and estradiol profiles in crossbred (Zebu x Holstein
Friesian) dairy cattle. Animal Husbandry, Dairy and Veterinary
Science 1(3), 63-71.
Melendez P, Donovan A and Hernandez J (2000) Milk urea nitrogen and
infertility in Florida Holstein cows. Journal of Dairy Science 83(3),
-463.
Mosaferi S, Ettehad S and Kooshavar H (2011) Study on the relationship
between milk urea nitrogen (MUN) and fertility in dairy cattle houses
in Tabriz. Veterinary Clinical Pathology the Quarterly Scientific
Journal 2(18), 1233-1245.
Muller CJC, Potgieter JP, Cloete SWP and Dzama K (2014) Non-genetic
factors affecting fertility traits in South African Holstein cows. South
African Journal of Animal Science 44(1), 54-63.
Munyaneza N, Niyukuri J and Hachimi YE (2017) Milk urea nitrogen
as an indicator of nitrogen metabolism efficiency in dairy cows: a
review. Theriogenology Insight-An International Journal of Reproduction
in all Animals 7(3), pp.145-159.
Nebel RL and McGilliard ML (1993) Interactions of high milk yield and
reproductive performance in dairy cows. Journal of Dairy Science
(10), 3257-3268.
Negrón-Pérez VM, Fausnacht DW and Rhoads ML (2019) Invited review:
Management strategies capable of improving the reproductive
performance of heat-stressed dairy cattle. Journal of Dairy Science,
(12), 10695-10710.
Nilforooshan MA and Edriss MA (2004) Effect of age at first calving on
some productive and longevity traits in Iranian Holsteins of the Isfahan
province. Journal of Dairy Science 87(7), -2135.
Norman HD, Wright JR, Hubbard SM, Miller RH and Hutchison JL (2009) Reproductive status of Holstein and Jersey cows in the United
States. Journal of Dairy Science 92(7), 3517-3528.
Ntallaris T, Humblot P, Båge R, Sjunnesson Y, Dupont J and Berglund
B (2017) Effect of energy balance profiles on metabolic and reproductive
response in Holstein and Swedish Red cows. Theriogenology
(12), 276-283.
Olivera-Muzante J, Fierro S, Alabart JL, Claramunt M, Minteguiaga MA,
Aunchayna G, Errandonea N and Banchero G (2019) Short-term dietary
protein supplementation improves reproductive performance of
estrous-synchronized ewes when there are long intervals of prostaglandin
or progesterone-based treatments for timed ai. Animal Reproduction
Science 206(3), 78-84.
Oltenacu PA and Broom DM (2010) The impact of genetic selection for
increased milk yield on the welfare of dairy cows. Animal Welfare
(1), 39-49.
Omur A, Kirbas A, Aksu E, Kandemir F, Dorman E, Kaynar O and Ucar
O (2016) Effects of antioxidant vitamins (A, D, E) and trace elements
(Cu, Mn, Se, Zn) on some metabolic and reproductive profiles in
dairy cows during transition period. Polish Journal of Veterinary Sciences
(4), 34-42.
Padalia H, Bharti RR, Pundir YPS and Sharma KP (2010) Geospatial
multiple logistic regression approach for habitat characterization of
scarce plant population: A case study of Pittosporum eriocarpum
Royle (an endemic species of Uttarakhand, India). Journal of the Indian
Society of Remote Sensing 38(3), 513-521.
Payne JM, Rowlands GJ, Manston R and Dew SM (1973) A statistical
appraisal of the results of metabolic profile tests on 75 dairy herds.
British Veterinary Journal 129(4), 370-381.
Pazzola M, Dettori ML, Carcangiu V, Luridiana S, Mura MC and Vacca
GM (2011) Relationship between milk urea, blood plasma urea and
body condition score in primiparous browsing goats with different
milk yield level. Archives Animal Breeding 54(5), 546-556.
Pongpiachan P, Rodtian P and Ota K (2003) Effects of tropical climate on
reproduction of cross-and purebred Friesian cattle in Northern Thailand.
Asian-Australasian Journal of Animal Sciences 16(7), 952-961.
Raboisson D, Albaaj A, Nonne G and Foucras G (2017) High urea and
pregnancy or conception in dairy cows: A meta-analysis to define the
appropriate urea threshold. Journal of Dairy Science 100(9), 7581-
Rahbar R, Sadeghi-Sefidmazgi A, Abdullahpour R and Nejati-Javaremi
A (2019) Can post-milking insemination increase conception rate
in high-producing Holstein cows under heat stress? A retrospective
study. The Journal of Agricultural Science 157(3), 254-259.
Rajala-Schultz PJ, Saville WJA, Frazer GS and Wittum TE (2001) Association
between milk urea nitrogen and fertility in Ohio dairy cows.
Journal of Dairy Science 84(2), 482-489.
Rangel, A.H.D.N., Soares, A.D., DE Lima, T.C.C., Araújo, T.P.M. and
Júnior, D.M.D.L., 2013. Concentration of urea nitrogen in buffalo
milk during different seasons of the year in Northeastern Brazil. Revista
Caatinga, 26(3): pp.99-104.
Reis Lacerda Medeiros AC (2020) Genetic correlation between milk urea
nitrogen and reproductive performance in seasonal grazing dairy
cows. a thesis presented in partial fulfilment of the requirements for
the degree of Master of Science (Animal Science) at Massey University,
Palmerston North, New Zealand (Doctoral dissertation, Massey
University). pp.94-100.
Rhoads ML, Rhoads RP, Gilbert RO, Toole R and Butler WR (2006) Detrimental
effects of high plasma urea nitrogen levels on viability of
embryos from lactating dairy cows. Animal Reproduction Science
(1-2), 1-10.
Ribeiro ES (2018) Symposium review: Lipids as regulators of conceptus
development: Implications for metabolic regulation of reproduction
in dairy cattle. Journal of Dairy Science 101(4), pp.3630-3641.
Rodney RM, Celi P, Scott W, Breinhild K and Lean IJ (2015) Effects of
dietary fat on fertility of dairy cattle: A meta-analysis and meta-regression.
Journal of Dairy Science 98(8), 5601-5620.
Rodney RM, Celi P, Scott W, Breinhild K, Santos JEP and Lean IJ (2018)
Effects of nutrition on the fertility of lactating dairy cattle. Journal of
Dairy Science 101(6), 5115-5133.
Roseler DK, Ferguson JD, Sniffen CJ and Herrema J (1993) Dietary
protein degradability effects on plasma and milk urea nitrogen and
milk nonprotein nitrogen in Holstein cows. Journal of Dairy Science
(2), 525-534.
Roy B, Brahma B, Ghosh S, Pankaj PK and Mandal G (2011) Evaluation
of milk urea concentration as useful indicator for dairy herd management:
A review. Asian Journal of Animal and Veterinary Advances
(1), 1-19.
Sadeghi-Sefidmazgi A, Moradi-Shahrbabak M, Nejati-Javaremi A, Miraei-
Ashtiani SR and Amer PR (2012) Breeding objectives for Holstein
dairy cattle in Iran. Journal of Dairy Science 95(6), 3406-3418.
SAS Institute (2001) SAS User’s Guide. Version 8.02 ed. SAS Institute
Inc., Cary, NC.
Schaeffer LR, Burnside EB, Glover P and Fatehi J (2011) Crossbreeding
results in Canadian dairy cattle for production, reproduction and conformation.
The Open Agriculture Journal 4(1), 422-428.
Seroussi E, Shirak A, Gershoni M, Ezra E, de Abreu Santos DJ, Ma L
and Liu GE (2019) Bos taurus-indicus hybridization correlates with
intralocus sexual-conflict effects of PRDM9 on male and female fertility
in Holstein cattle. BMC Genetics 20(1), 1-11.
Sewalem A, Miglior F, Kistemaker GJ, Sullivan PV and Van Doormaal
BJ (2008) Relationship between reproduction traits and functional
longevity in Canadian dairy cattle. Journal of Dairy Science 91(4),
-1668.
Shelton K, Parkinson TJ, Hunter MG, Kelly RW and Lamming GE (1990)
Prostaglandin E-2 as a potential luteotrophic agent during early pregnancy
in cattle. Reproduction 90(1), 11-17.
Sklan D and Tinsky M (1993) Production and reproduction responses by
dairy cows fed varying undegradable protein coated with rumen bypass
fat. Journal of Dairy Science 76(1), 216-223.
SM A and Estuty N (2021) Nutritional effects on dairy cattle fertility. International
Journal for Research in Applied Sciences and Biotechnology
(4), 71-82.
Sonderman JP and Larson LL (1989) Effect of dietary protein and exogenous
gonadotropin-releasing hormone on circulating progesterone
concentrations and performance of Holstein cows. Journal of Dairy
Science 72(8), 2179-2183.
Souza FRD, Campos CC, Silva NAMD and Santos RMD (2016) Influence
of seasonality, timing of insemination and rectal temperature on
conception rate of crossbred dairy cows. Semina: Ciências Agrárias
-162.
Souza VC, Aguilar M, Van Amburgh M, Nayananjalie WAD and Hanigan
MD (2021) Milk urea nitrogen variation explained by differences in
urea transport into the gastrointestinal tract in lactating dairy cows.
Journal of Dairy Science 104(6), 6715-6726.
Soydan E and Kuran M (2017) The effect of calving season on reproductive
performance of Jersey cows. Mljekarstvo/Dairy 67(4), 362-369.
Spooner MK, Lenis YY, Watson R, Jaimes D and Patterson AL (2021)
The role of stem cells in uterine involution. Reproduction 161(3),
R61-R77.
Staples CR, Thatcher WW and Clark JH (1990) Relationship between
ovarian activity and energy status during the early postpartum period
of high producing dairy cows. Journal of Dairy Science 73(4), 938-
Starbuck GR, Darwash AO, Mann GE and Lamming GE (2001) The detection
and treatment of post insemination progesterone insufficiency
in dairy cows. BSAP Occasional Publication 26(2), 447-450.
Summar ML, Koelker S, Freedenberg D, Le Mons C, Haberle J, Lee HS,
Kirmse B, Registry TE and Members of the Urea Cycle Disorders
Consortium (2013) The incidence of urea cycle disorders. Molecular
Genetics and Metabolism 110(1-2), 179-180.
Tillard E, Humblot P, Faye B, Lecomte P, Dohoo I and Bocquier F (2007)
Precalving factors affecting conception risk in Holstein dairy cows in
tropical conditions. Theriogenology 68(4), 567-581.
Van den Berg I, Ho PN, Haile-Mariam M, Beatson PR, O’Connor E and
Pryce JE (2021) Genetic parameters of blood urea nitrogen and milk
urea nitrogen concentration in dairy cattle managed in pasture-based
production systems of New Zealand and Australia. Animal Production
Science 114(3), 648-652.
Vasconcelos JLM, Silcox RW, Rosa GJM, Pursley JR and Wiltbank MC
(1999) Synchronization rate, size of the ovulatory follicle, and pregnancy
rate after synchronization of ovulation beginning on different
days of the estrous cycle in lactating dairy cows. Theriogenology 52(6), 1067-1078.
Veen WAG and Bakker YT (1988) The influence of slowly and rapidly
degradable concentrate protein on a number of blood parameters in
dairy cattle. Netherlands Journal of Agricultural Science 36(1), 51-
Walsh SW, Williams EJ and Evans ACO (2011) A review of the causes of
poor fertility in high milk producing dairy cows. Animal Reproduction
Science 123(3-4), 127-138.
Wathes DC, Taylor VJ, Cheng Z and Mann GE (2003) Follicle growth,
corpus luteum function and their effects on embryo development in
postpartum dairy cows. Reproduction Supplement 61(4), 219-237.
Wiltbank MC, Souza AH, Carvalho PD, Cunha AP, Giordano JO, Fricke
PM, Baez GM and Diskin MG (2014) Physiological and practical
effects of progesterone on reproduction in dairy cattle. Animal 8(s1),
-81.
Wiltbank MC, Souza AH, Giordano JO, Nascimento AB, Vasconcelos
JM, Pereira MHC, Fricke PM, Surjus RS, Zinsly FCS, Carvalho PD
and Bender RW (2018) Positive and negative effects of progesterone
during timed AI protocols in lactating dairy cattle. Animal Reproduction
(3), 231-241.
Yan L, Robinson R, Shi Z and Mann G (2016) Efficacy of progesterone
supplementation during early pregnancy in cows: A meta-analysis.
Theriogenology 85(8), 1390-1398.
Yasothai R (2014) Importance of minerals on reproduction in dairy cattle.
International Journal of Science, Environment and Technology 3(6),
-2057.
Yoon JT, Lee JH, Kim CK, Chung YC. and Kim CH (2004) Effects of milk
production, season, parity and lactation period on variations of milk
urea nitrogen concentration and milk components of Holstein dairy
cows. Asian-Australasian Journal of Animal Sciences 17(4), 479-484.
