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Infections with the blood sucking parasite, Haemonchus contortus, are of primary concern for small ruminant producers, especially due to the prevalence of anthelmintic resistance. The objective of this study was to determine the effectiveness of copper oxide wire particles alone (COWP; n = 12; 1 g bolus Copasure; Animax Ltd), Cydectin alone (CYD; n = 10; 0.4 mg/kg; Bayer), a combination of COWP + CYD (n = 12) and an untreated control group (CON; n = 11) in reducing fecal egg counts (FEC) in meat goat kids. At weaning (88.4 ± 0.7 d), 45 meat goat kids with FAMACHA scores = 3 and weighing 12.5 ± 0.4 kg were separated into the four treatment groups after accounting for initial FAMACHA eyelid color score, breed (Spanish or Myotonic), and birth type (single or multiple). Feces were collected on d 0 and 14 for determination of FEC. Pooled treatment group feces were also cultured on d 0 and 4 to determine gastrointestinal nematode (GIN) genera. Individual FEC were calculated, and treatment efficacy was determined according to the guidelines established by the World Association for the Advancement of Veterinary Parasitology. FEC were log transformed and analyzed using repeated measures in a mixed model with d 0 FEC as a covariate. Individuals were removed from the study if d 0 FEC was less than 400 eggs/g (n = 3, n = 3, n = 2, and n = 2 for CON, COWP, CYD and COWP + CYD, respectively). There was a mixed population of GIN cultured from pooled fecal samples (averaging 70.3%, 17.7%, and 12.0% for H. contortus, Tricostrongylus spp., and Oesphagostomum spp., respectively). Pre-treatment FEC averaged 1,262 ± 241, 2,794 ± 765, 2,050 ± 378 and 1,375 ± 221 eggs per gram (epg), for the CON, COWP, CYD and CYD+COWP, respectively. There was an effect of treatment on FEC with FEC on day 14 less (P < 0.05) for COWP (497 ± 200 epg), CYD (746 ± 334 epg) and COWP + CYD (559 ± 246 epg) treated kids than CON (1,701 ± 895 epg). CON group FEC increased by 35% while treatment with COWP reduced FEC by 71% (84 - 92% Confidence Interval; CI), compared with 56% (60 - 89% CI) for CYD and 67% (88 - 90% CI) for COWP + CYD. Even though all treatments were more effective than the CON, the effect of COWP + CYD was similar to COWP and CYD when used alone and no additive effect was observed. Under the conditions of this study, COWP, COWP + CYD and CYD were all effective in reducing FEC compared with leaving meat goat kids untreated. [ABSTRACT FROM AUTHOR]

Small ruminant production in the US is significantly impacted by infections with gastrointestinal nematodes (GIN), especially the blood sucking GIN, Haemonchus contortus. Unfortunately, the indiscriminate use of available drug classes has led to multi-drug resistant GIN that pose significant challenges to parasite control on many farms. The objective of this study was to evaluate the effectiveness of a natural fungus, Duddingtonia flagrans (Bioworma, International Animal Health) in reducing GIN loads in lactating meat does. Thirty eight late gestating Spanish and Myotonic does were dewormed (day 0) approximately 2 weeks before to kidding with a combination of levamisol (Prohibit; 12 mg/kg BW) and moxidectin (Cydectin; 0.4 mg/kg BW) before the start of feeding BioWorma according to the manufacturer's recommendations. At this time, does were also allocated into two treatment groups (n = 19/group), split into 3 replications per treatment and placed on six pasture paddocks (n = 6/7 per paddock). Does were then fed either a corn and soybean meal supplement at 1.5% of their BW with (BIO) or without (CON) Bioworma daily until weaning and hay was offered throughout the study. Bioworma was added to the ration based on the manufacturer's recommended dose of 0.066 g/kg BW and on the BW of the heaviest doe. To evaluate the effect of Bioworma treatment, BW, body condition score (BCS), and FAMACHA scores were recorded every 2 weeks for 98 days. Blood and fecal samples were also collected for determination of packed cell volume (PCV) and fecal egg counts (FEC). Pooled (d 28) or pooled treatment group feces (d 42, 56, 70, 84 and 98) were also collected and cultured to determine GIN genera. If blood PCV decreased to below 19%, does were dewormed and removed from the study (n = 2 BIO; n = 2 CON). Data were analyzed using repeated measures in a mixed model, and FEC were log transformed before analysis. Following deworming (d 0), FEC were reduced by 97% by d4. There was a mixed population of GIN throughout the study (averaging 70.3%,7.7%, and2.0% for H. contortus, Tricostrongylus spp., and Oesphagostomum spp., respectively). Bioworma supplementation had no impact on BW, BCS, FAMACHA scores, nor PCV averaging 38.8 ± 0.5 kg, 2.3 ± 0.03, 2.2 ± 0.02, and 29.3 ± 0.3%, respectively. There was also no effect of treatment on FEC (averaging 1,067±254 and 1,107±144 and 987±282 and 847±163 eggs per gram for BIO and CON does on days 0 and 98, respectively. Bioworma supplementation in a highly susceptible group of lactating does, had no influence on GIN indicators. Additional research is needed to confirm the efficacy of Duddingtoni flagrans in controlling GIN and how best to incorporate in current on-farm parasite control strategies. [ABSTRACT FROM AUTHOR]

Energy is often the most limiting nutrient in pasture diets. The effect of energy supplementation on the growth, health, and carcass traits of pastureraised lambs was investigated. Seventy-nine Katahdin ram lambs were delivered to the Western Maryland Research & Education Center on June 15. After an 11-d acclimation period, lambs were allocated to two treatment groups based on age, weight, birth type, and FEC. Lambs in the PASTURE group (n = 40) rotationally grazed 2 ha of high quality, mixed pasture for 102 d. Lambs in the SUPPL group (n = 39) grazed similar pastures and were hand-fed a daily energy supplement (450 g of whole barley). The groups were handled bi-weekly to determine body weights, FAMACHA©, BCS, and dag scores. Individual fecal samples were collected upon arrival and at two additional time points. Lambs were ultrasound scanned on Sept 25 to determine carcass traits. Data were analyzed using the MIXED procedure of SAS, with statistical significance set at P ≤ 0.05. ADG varied considerably among weigh periods. Standard deviations were typically quite large, indicating wide variation in individual performance. Overall, the SUPPL lambs had higher ADG (P < 0.01), more backfat (P < 0.03), and higher BCS (P < 0.01) than the PASTURE lambs. There were no statistical differences in starting weight, ending weight, and loin depth. While internal parasites were not a problem during the study (only one lamb had a FAMACHA© score >4), PASTURE lambs had lower FEC (P < 0.05) on August 17 (240 ± 81 vs. 468 ± 80 epg). The value of additional gain (0.9 kg) would not have covered the cost of feed; however, four lambs were removed from the PASTURE group (due to death or failure to thrive) whereas only two lambs were removed from the SUPPL group. The study will be repeated in 2021 with similar lambs and protocol. [ABSTRACT FROM AUTHOR]

Reduced anthelmintic efficacy in beef cattle has recently been documented at the national level. The objective of this study was to determine if anthelmintic resistance is present in Maryland beef cattle herds. For this study, the fecal egg count reduction (FECR) test was used to assess anthelmintic efficacy of composite samples. Between July and October 2020, anthelmintic efficacy was assessed for 17 groups of cattle across 14 individual farms in Maryland. Each test group consisted of 24 ± 6 calves or yearlings (< 16 months of age). Previous anthelmintic treatment history was used to assign each group to one of four commercially available anthelmintics: moxidectin (injectable), moxidectin (pour-on), doramectin, or fenbendazole. Prior to treatment, cattle were weighed to ensure appropriate dose according to the product label. Fecal samples were collected from all cattle within each group before and after (17 ± 5 d) treatment. Pre- and post-treatment samples were composited for each group on an equalweight basis (10g per animal) and the number of eggs within the sample was determined using the 3-chambered McMaster technique. The mean FECR across all four anthelmintics was 60 ± 19% (mean ± 95% confidence interval), indicating that the anthelmintics tested in this study were largely ineffective. The FECR for the moxidectin injectable, moxidectin pour-on, doramectin, and fenbendazole treatments were 71 ± 38%, 47 ± 46%, 35 ± 88%, and 96 ± 18% (mean ± 95% confidence interval), respectively. Although these data indicate no statistically significant differences for efficacy among the four products tested, they do suggest that efficacy is highly variable across different anthelmintics and farms. Results also indicate that anthelmintic resistance exists on many cattle farms in Maryland. This study provides evidence that supports the need for more judicious anthelmintic use and alternative gastrointestinal parasite control measures in Maryland beef cattle herds. [ABSTRACT FROM AUTHOR]

A follow-up study was conducted to validate observations from an earlier trial on reproductive function in ram lambs following short scrotum castration. Again, East Friesian x Lacaune male dairy lambs from a commercial sheep dairy born in February and March were either left intact (IN, n=25), rendered short-scrotum (SS; n=18), or completely banded (WE; n=25) within 10 d of birth. At a mean age of 65 d, lambs were moved to the study site and managed as one group on cool season forages and supplemented with grain at 2–3% BW. At a mean age of 172 d, lambs were tested for libido in a 5 min pen test, and semen was collected from 7 IN and 7 SS lambs. Four estrus-induced teaser ewes were used for libido testing and semen collection by artificial vagina. Lambs were harvested the day after testing/collection, and reproductive tracts were recovered from 5 IN and 5 SS lambs at random. Differences between male lamb types were analyzed using PROC GLM. No statistical differences (P >0.05) in reproductive behaviors were observed between IN and SS, though number of services and kicks were numerically higher in IN than SS (1.3 vs. 0.45; 1.6 vs. 0.73). No reproductive behaviors was observed in WE. Ejaculate volume was not different between IN and SS (0.56 vs. 0.49 ml), but percent motile sperm (45 vs. 6 %; P< 0.01) and sperm concentration (1.52 vs. 0.05 billion/ml; P< 0.05) were higher in IN then SS lambs. Total testis and epididymis weight were also higher (P< 0.01) in IN than SS lambs (291 vs. 109 g; 53.8 g vs. 17.7 g). Additionally, epididymal sperm reserves were higher (P< 0.05) in IN than SS (9.42 vs. 0.89 billion) lambs. Results confirm our earlier findings that reproductive function was greatly reduced, but did not cease in short scrotum ram lambs. [ABSTRACT FROM AUTHOR]

Short-scrotum (induced cryptorchid) rams can retain growth and performance characteristics of intact-rams while making them sterile and facilitating co-grazing with ewe-lambs. East Friesian x Lacaune male lambs left intact (n = 19; IN), rendered short-scrotum (n = 17; SS) or neutered (n = 25; WE) by 10 d of age, were used to evaluate libido and semen quality at 7-mo old. Lambs were managed as one group on a forage-based diet supplemented with a grain mixture (barley and soybean meal at 0.7 kg/d). Four CIDR-treated estrus-induced ewes were placed two/pen in adjacent 2.5x2.5 m pens for libido testing. Males were introduced individually to ewe pens for 5 min and reproductive behaviors recorded (anogenital sniffs, foreleg kicks, flehmen, false mounts, and service). Semen was collected from 6 random IN and SS lambs via artificial vaginas using estrus-induced ewes as teasers. Volume was recorded, and ejaculate extended in milk/egg yolk, packaged into straws, and stored at 5°C for analysis with a CASA system the following day. Behavior measurements were compared between types using PROC GLM. Ejaculate characteristics are presented as mean±SD due to insufficient sperm concentrations of SS ejaculates. Anogential sniffs, foreleg kicks, and mounts were similar in IN and SS, and higher (P < 0.05) than in WE (7.44 and 6.34 vs. 4.76; 1.72 and 1.60 vs. 0.17; 1.78 and 2.05 vs. 0.22; respectively). Number of services were higher (P < 0.001) in IN than SS (1.11 vs. 0.53), but time to service (112 sec) was not different. Ejaculate volume was similar in IN and SS (0.51 mL), but SS ejaculates were essentially devoid of sperm. Ejaculates from IN lambs had 0.69x109±0.48 x109 sperm, with 68.9±12.5% progressive motility, 81.8±6.1% viability and 87.1±6.1% morphologic normality. Ram lambs rendered short-scrotum by 10 d of age had reproductive behavior similar to intact post-pubertal rams, but ejaculate characteristics showed them to be sterile [ABSTRACT FROM AUTHOR]