Livestock Pathogens of Waterborne & Public Health Concern:

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1 Ambient conditions and monitoring for livestock associated pathogens and indicators in CA waterways 1. Overview of pathogens and indicator bacteria of concern. 2. Indicator bacteria dynamics in runoff from rangeland and irrigated pasture.. Correlations between indicator bacteria and pathogens of concern. C. hild C. parvum Type of organism Protozoa Bacteria U.S. waterborne disease outbreaks causing gastroenteritis 1989 through 1996 Agent No. outbreaks Drinking water Water recreation Giardia duodenalis Cryptosporidium Campylobacter jejuni C. parvum Pathogens and produce: rangeland runoff and irrigation water A decade of produce outbreaks traced back to CA Year Food Vehicle Mesclun lettuce Unpasteurized apple juice Alfalfa or clover sprouts (6 outbreaks) Raw almonds Romaine lettuce Raw almonds Baby spinach Baby spinach Iceberg lettuce Iceberg lettuce Pathogen Cases Livestock Pathogens of Waterborne & Public Health Concern: Protozoa: hard to eliminate during water treatment, low infectious dose, mild to moderate illness Cryptosporidium parvum Giardia duodenalis Bacteria: easy to eliminate during water treatment, higher infectious dose, mild to serious illness pathogenic (e.g., Stx 1&2, O157:H7) Campylobacter 1

2 Indicator bacteria v. pathogens total coliforms, fecal coliforms, indicator, Enterococcus Bacteria that when present in water indicate the presence of fecal material and pathogens. C. parvum E. Coli O157:H7 Ideal world: strong, reliable correlation between indicator bacteria and bovine pathogens in water C. parvum (oocysts / L) A standard is born indicator (cfu/1ml) Indicator Bacteria Standards: Surface Waters Fresh water standards exist for both indicator and fecal coliforms across CA: varies by water board USEPA Recommends 1. geometric mean <126 bacteria per 1 ml from 5 samples in days Indicator Bacteria: One Big Happy Family total coliforms fecal coliforms indicator 2. single grab samples should not exceed 25 bacteria per 1 ml : : A malcontent in every family Beef cattle - indicator bacteria pathogenic indicator Shiga-toxin outbreak strain Fecal coliforms: 1,, to 1,, per gm feces all classes O157:H7 Indicator : 1,, to 1,, per gm feces all classes. 2

3 Indicator dynamics in runoff from rangeland and irrigated pasture. Small watershed scale annual rangelands Spatial Scale: Pasture to the watershed to the Delta. Temporal Scales: Runoff event to the water year. Ramifications for monitoring and meeting water quality standards. Experimental watersheds HREC (7), SFREC (4) Grazing and fire treatments 2 to acres in size HREC SFREC SFREC heavy grazing/rangeland can observe an order of Schubert Watershed Winter Storm Dec , 21 magnitude acre catchment or greater on UC-SFREC change in Sierra Nevada during foothill a oak storm woodlands, event. grazed by beef cattle , E.coli (cfu/1ml) FC (cfu/1ml) 8, 6, 4, 2, Fecal Colif. & (cfu/1 ml) SFREC heavy grazing/rangeland can observe an significant reduction in concentration from start to end of rainfall season. 9 6 Watershed 4: 22 Winter Stormflow acre catchment on in Sierra Nevada annual range, winter graze, cow-calf, 5 lb/ac RDM E.coli (cfu/1ml) FC (cfu/1ml) 25, 2, 15, 1, 5, Fecal Colif. & (cfu/1 ml) : 12: : 12: : 12: : 12: : 12: : 12: 2-Nov 27-Nov 22-Dec 17-Jan 11-Feb 9-Mar -Apr 28-Apr Two storms in mid December One rainfall-runoff season HREC observe variable differences between moderately grazed and non-grazed watersheds, background does not =. Concentration (cfu/1ml) Mean generic and fecal coliform concentrations from 4 oak woodland watersheds at UC-HREC near Hopland, CA during 21 WY Moderately grazed A B C D Watershed fecal coliform Non-grazed since Valley and Foothill Irrigated Pastures Flood Irrigated Pasture

4 Levels in Irrigated Pasture Tailwater A 7 hour irrigation event Levels in Irrigated Pasture Tailwater 8 Irrigation Events Tailwater Runoff Rate (cfs) Runoff (cfu/1ml) cfu/1 ml tailwater irrigation water grazing management Time of Day Jun. Sep. Two Year Survey of WQ in 24 California rangeland streams Indicator and FC concentrations were dependent 2 & 21 ~1 grab samples under storm and base flow conditions Concentration (cfu/1ml) 9, 6,, Mean generic and fecal coliform concentration measured for 2 years upon on 24 rangeland watershed streams hydrology across California (n=947 elevation samples) Rainfall-Runoff Rainfall-Runoff & Snowmelt Snowmelt fecal coliform B F G H I K N Q V X A C E P T U D J L M O R S W Stream Indicator and FC concentrations were variable Mean monthly indicator bacteria concentrations across 14 coastal and across foothill annual the water rangeland year streams on annual WY range watersheds fecal coliforms mobilization of in-stream sediment Delta Project: 88 sites monitored once a month for two years Bacterial indicators: fecal coliforms,, Enterococcus Bacterial pathogens:, shigatoxin 1&2, Campylobacter cfu/1 ml 6 4 irrigated pasture return environmental growth? 2 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep 4

5 SAC 8% 6% Indicator 6/6-6/7, 12/7-11/8, n=1892 7% of samples < 25 cfu RIO VISTA Frequency 4% STOCKTON 2% % 5% of samples > 25 cfu (cfu / 1 ml) indicator bacteria = pathogens in water? Unknown correlations between indicators and livestock associated pathogens for CA watersheds. C. parvum (oocysts / L) Ideal Correlation indicator (cfu/1ml) % infected Consider the shedding of pathogens and indicators in CA range and pasture cattle feces. 1 C. parvum in CA range cattle calves 5-15% 1, / g cows <1% 1-1 / g cattle age (months) Indicator in CA range cattle cows and calves 1% 1, 1,, / g Annual Rangeland SFREC & HREC 8 grazed rangeland watersheds 2 years Trace C. Parvum levels in <5% of ~6 stream samples 9 12, E.coli (cfu/1ml) 6 8, 4, 11/2/1 11/27/1 12/22/1 1/17/2 2/11/2 /9/2 4//2 4/28/2 (cfu/1 ml) 5

6 UFRW and Bridgeport Valley: 27-8 Graze Season (May Oct) Sample monthly: indicator and FC, C. parvum,, E. Coli O157:H7, Campylobacter Sample a total 16 sites: entering and exiting irrigated agriculture areas Irrigation, beef cattle grazing, hay production Pathogen monitoring UFRW and Bridgeport Valley water samples taken, May-Oct indicator < 25 cfu/1 ml > 25 cfu/1 ml Crypto 8=Yes 5 of 75 (6%) of 27 (11%) 12=Yes 9 of 75 (12%) of 27 (11%) Campy =Yes of 75 (%) of 27 (%) 1, to 2, AU 1,5 to 2, ac irrigated 6=Yes 4 of 95 (4%) 2 of 21 (9%) Pathogen monitoring UFRW and Bridgeport Valley SAC above meadow below meadow Crypto 8=Yes 5 RIO VISTA 12=Yes 1 2 Campy =Yes O157:H7 6=Yes 6 STOCKTON Delta pathogen indicator monitoring 955 water samples, Not so Ideal World: indicator concentrations not well correlated to, C. parvum,, etc. 1 Mean Conc. indicator < 25 cfu/1 ml > 25 cfu/1 ml Indicator 22 cfu 47 cfu. MPN.25 MPN 1,829 isolates from across these 955 samples 2 of 1,829 had Stx 1 (.1%) 2 of 1,829 had Stx 2 (.1%) (cfu/1ml) indicator (cfu/1ml) 6

7 Pathogen (no. / 1 ml) Possible Correlation at higher indicator levels? , 4, 6, 8, 1, Indicator bacteria (no. / 1 ml) Summary Significant indicator bacteria associated with direct range and pasture runoff, Conc. reduction with increased spatial scale: pasture>watershed>delta, Significant influence of watershed hydrology and livestock management on conc., Conc a ithin noff e ents (ho l ) Summary We consistently find very low levels of pathogens in these waters, Essentially non-existent correlations between pathogens and indicator bacteria in these waters, Management opportunities do exist to reduce microbial pollutant loads from these systems next topic 7