@conference {60936,
	title = {Effects of sub-clinical endometritis on ovarian follicular activity in postpartum dairy cows},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {69},
	year = {2009},
	month = {Jun},
	pages = {32-36},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Christchurch},
	abstract = {The effects of sub-clinical endometritis (scEndo) on ovarian follicular activity in pasture-fed dairy cows were determined. The uterine-health status of lactating dairy cows (n = 169) was assessed on day (D) 21 ({\textpm} 3 days) postpartum by Metricheck. In a sub-population (n = 47; 32 clean, 15 scEndo), Metricheck assessment was repeated on D42 and uterine cytology undertaken on D21 and D42 [scEndo = polymorphicnuclear (PMN) cells >18\%]. Follicular activity was assessed by ultrasound on D42 and D63. Metricheck evaluation revealed that the proportion of cows with scEndo was 15/169 (8.9\%) and 4/47 (8.5\%) on D21 and D42 respectively. Irrespective of the method used to determine scEndo, dominant (P <0.001) but not subordinate (P >0.1) follicles were larger and grew faster on D63 than on D42. Based on the D21 Metricheck but not the \%PMN classification, dominant follicles of scEndo cows were larger and grew faster (P = 0.02) than those in clean cows. No overall effect of uterine status was found on the subordinate follicles, although these tended (P = 0.06) to be larger on D63 than on D42 but only in clean cows. Thus early postpartum scEndo appears to modulate the subsequent size of the dominant follicle. However, it remains to be determined whether this affects the subsequent fertility of these cows. },
	issn = {1176-5283},
	author = {Back PJ and Ledgard AM and Beaumont S and Berg MC and Peterson AJ and McNatty KP and Green MP}
}
@conference {41283,
	title = {Relationship between bulk milk urea nitrogen and reproductive performance of New Zealand dairy herds},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {61},
	year = {2001},
	month = {Jan},
	pages = {192-194},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Christchurch},
	abstract = {New Zealand dairy cows grazing lush spring pasture have relatively high plasma urea nitrogen levels as a consequence of the high soluble crude protein content of this rapidly growing pasture. The elevated plasma urea levels have been implicated as a cause of poor reproductive performance in dairy herds. The aim of this trial was to determine if the bulk milk urea nitrogen levels (BMUNs) collected during the period from calving and through mating were related to the reproductive performance of the herds. Bulk milk samples were collected twice a week from 127 farms during the spring of 1998. The farms were suppliers of the NZ Dairy Group and Kiwi co-operatives. Reproductive performance data was collected from all herds. BMUNs were determined spectrophotomically using Sigma blood urea nitrogen kits. The twice-weekly BMUNs were averaged for each farm and these weekly mean values were centred on the nominated week of mating (W=+1) for the individual farms. There were significant among-farm differences in BMUNs with individual weekly farm values ranging from 5.4 to 26.8 (mg/dl) and the mean (W-3 to W+5) value for farms ranging from 9.6 to 18.8 (mg/dl). There were significant between farm differences in reproductive performance. The percentage of cows submitted for AI in first 3 weeks of mating (\%SR21) ranged from 29.9 to 95.3\%. The percentage of SR21 cows conceiving to that AI (\%Preg1) ranged from 39 to 98.6\% and the percentage of all cows in the herd pregnant by the end of mating (\%Pregall) from 44.9 to 98.4\%. There was some indication of a relationship between reproductive performance and BMUNs in that the change in BMUN level from W-3 to W+5 was significantly correlated within geographic zones with \%SR21 and \%Pregall, correlation coefficients being 0.36 (P=0.013) and 0.37 (P=0.010) respectively. The corresponding correlation for \%Preg1 was only 0.21(P = 0.15). Thus farms for which BMUNs rose over the period W-3 to W+5 had higher reproductive performance than those in the same zone, which showed a fall. However, this accounted for very little of the overall variability. Farms were ranked on their reproductive performance and the average weekly BMUNs for the farms in each quartile calculated. There was no difference in the pattern of BMUNs for the different quartiles of each reproductive parameter. Thus, the measurement of BMUNs would appear to be of little value as an indicator or predictor of reproductive performance. },
	issn = {1176-5283},
	author = {Smith JF and Beaumont S and Hagemann L and McDonald RM and Peterson AJ and Xu ZZ and Duganzich DM}
}
@conference {40726,
	title = {Comparison of cervical, transcervical and laparoscopic insemination of ewes with chilled stored and frozen ram semen},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {55},
	year = {1995},
	month = {Jan},
	pages = {248-250},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {A technique for transcervical artificial insemination (TAI) of the ewe  has been reported as an alternative to laparoscopic intrauterine insemination  (LAI). This study evaluated the techniques under New Zealand conditions.   Romney ewes (365) were treated in February for 14 days with CIDR},
	issn = {1176-5283},
	author = {Smith JF and Parr J and Beaumont S and Oliver JE and Upreti GC}
}
@conference {40725,
	title = {Effect of diluent type and storage time on the pregnancy rate of ewes inseminated laparoscopically with chilled ram semen},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {55},
	year = {1995},
	month = {Jan},
	pages = {245-247},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Five trials involving 879 ewes were conducted in November,  December 1993, February, March and April 1994. Ewes were synchronised  with CIDR},
	issn = {1176-5283},
	author = {Smith JF and Parr J and Murray G and Oliver JE and Beaumont S and Upreti GC}
}
