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21.  Livestock company that has a web presence: Erk Ranch of Newell. 

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21.  Livestock company that has a web presence: Erk Ranch of Newell. 

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I chose this company because they have been recognized by the South Dakota Sheep Growers Association (SDSGA) for their sheep production, public awareness and their excellent husbandry/ genetics. The ranch doesn't have an official website but they have a facebook page where they can connect with the public.

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BROOKINGS, S.D.- During the 81st annual convention of the South Dakota Sheep Growers Association (SDSGA) held September 28-29 in Brookings, two award-winning sheep operations were recognized with the South Dakota Master Lamb Producer award.

This 35-year-old honor, was bestowed upon Tom and Marilyn Schwebach of Egan and the Erk Ranch of Newell.

"These two operations are outstanding examples, showcasing the quality of the South Dakota sheep industry," said Jeff Held, Professor & SDSU Extension Sheep Specialist. "And, what makes it even better, is that they have the next generation involved to move forward into the future."

More about honorees

Tom and Marilyn Schwebach, Egan

Tom and Marilyn Schwebach run an 850-head commercial flock of Ile de France ewes which have highly productive maternal lines producing outstanding finished lambs for the packer and reputation replacement females for the industry.

Unique flock management features include: a flock health plan of OPP-free (ovine progressive pneumonia) status for the past 20 years and a grazing management plan implemented 15 years ago, in cooperation with the South Dakota Grasslands Council, resulting in a 50 percent increase in grazing capacity.

The Erk Ranch, Newell

For more than 100 years, the Erk Ranch has produced feeder lambs and high quality wool in Butte County. Currently the operation runs more than 1,000 Rambouillet ewes including 300 registered animals.

Range rams offered from the Erk Ranch to the industry have a strong reputation for superior wool traits, both fine fiber diameter and long staple length. For decades they have worked to improve economically important wool traits by selecting studs based objective measures of wool quality.

Future flock genetic advancements in wool quality traits will be aided by wool Expected Breeding Value (EBV) values generated from the National Sheep Improvement Program and individual ewe performance data collected using the Shearwell Data System.

Trapper & Shepherds Awards

The South Dakota Sheep Gowers Association also recognized other supporters of the industry.

Brent Vander Ley, Chamberlain, received the Trapper of the Year award.

"Brent has been with South Dakota Game, Fish and Parks for over 20 years and works tirelessly on the sheep producers behalf," said Steve Clements, director for South Dakota Sheep Growers Association, and serves as chair of the American Sheep Industry Predator Management Committee.

Todd Nordmann and Steve DeGroot of Sioux Falls Regional Livestock, Worthing, with the Shepherd's Award.

"The competitive bidding for all classes of sheep at Sioux Falls Regional Livestock sets the pace for "price discovery" for this region and is considered a key national market index for both feeder and finished lamb sold," Held said.

More than a decade ago Sioux Falls Regional Livestock facility was built primarily to serve cattle producers, yet a weekly sheep and goats sale was also held. By 2009, demand for a strong sheep and goat market rose sharply when the Stockyards in Sioux Falls closed.

The ownership group for Sioux Falls Regional Livestock asked Steve DeGroot, Orange City, Iowa and Todd Nordmann, Chancellor to establish a weekly sheep and goat auction. Working together for more than 20 years in a commission firm capacity at the Sioux Falls Stockyards, the men earned a reputation with producers of providing marketing excellence in the sheep and goat alleys.

With their expertise and leadership, the number of sheep and goats sold has increased more than 50 percent with continued growth expected into the future. In 2017, sales topped 68,000 head.

New leadership

Elections were also held during the convention. Sheep producer, Wade Kopren, Bison was elected to serve as president, as Rufus DeZeeuw, Elkton, completed his two-year term serving as president.

Three producers were elected to serve on the board of directors: Kris Schweigert, Gregory; Lisa Dennert, Frederick and Scott Kilber, Ipswich. These directors will serve four-year terms, filling vacated director seats left open by Steve Clements, Tom Dosch and Tim Flint.

Workshops, contests & more

In addition to elections, several in-depth workshops were held. Led by experts in the field, the workshops were designed to help sheep producers with: marketing and selection utilizing ultrasound technology; learn more about lamb cuts and processing; and ultimately improve their bottom line.

Educational presentations were also held, covering a variety of topics including: grazing management and cover crops; predator management resources; Natural Resources Conservation Service Rainfall Simulator; lambing time management and wool quality improvement.

Presentations were also provided by Jeff Held, Professor & SDSU Extension Sheep Specialist and Dave Ollila, SDSU Extension Sheep Field Specialist. The SDSU Extension staff reviewed current research and SDSU Extension programming. SDSGA and SDSU Extension have a long-standing partnership supporting the South Dakota sheep industry.

Chris Diaz, USDA-Agriculture Marketing Service, reviewed lamb and wool prices. South Dakota fine wools saw record prices in 2018. Diaz shared that based on market indications, growers should look for this trend to hold for the upcoming 2019 shearing season.

Regionally, average wool prices were around $3 greasy. This is a dollar above last year's prices.

Peter Orwick, the American Sheep Industry, Executive Director, covered current issues and sheep industry updates.

Jim Percival, American Lamb Board President, reviewed priorities for lamb promotions.

Steve DeGroot, Sioux Falls Regional Livestock and Mike Caskey, Pine Lawn Farms discussed marketing trends in the lamb industry.

Miss South Dakota, Carrie Wintel, made a special appearance during the convention's Lamb Lover's Social, where a wide variety of lamb appetizers were featured.

The Lamb Lover's Social is a family-friendly social which featured a lamb BBQ Bootcamp, trade show booths, a fun speed shearing contest.

Make it With Wool

The State Finals of the Make it With Wool contest was held September 29 in conjunction with an evening social, live and silent auction (proceeds used for education & promotion activities) and SDSGA awards banquet.

The award winners including the following:

Pre-teen: Lexy Faulhaber, Plankinton

Junior: Cortney Olinger, Plankinton. Olinger will advance to the National Make It With Wool contest held in New Orleans.

Senior: Susan Roth. Roth cannot attend the national competition so alternate, Allison Duerre, Bristol, will compete in New Orleans.

Adult: Anna Erk, Newell will compete in New Orleans.

Professional: Koreen Anderson, Lemmon. Anderson will represent South Dakota in the National MIWW. She will submit her garment and a video of her modeling.

Made for others: Denise Muntefering, Dimock. Muntefering sewed outfits for her three grandchildren.

Wearable Accessory: Haile Stuck, Brentford. Stuck spun the yarn from her own sheep and made a finger knitted scarf.

South Dakota Special Contest:

Challenge: Stephanie McCord, White Lake

Quilt: Barb Hoff, Madison

Novelty: Charlette Kvale, Lemmon

Knitted accessory: Mina Doerner, Brookings

To learn more about South Dakota Sheep Growers Associations contact Lisa Surber, Executive Secretary SDSGA by email or online.

And, for more information about upcoming SDSU Extension sheep activities, contact Held by email or 605.688.5433 or Dave Ollila, SDSU Extension Sheep Field Specialist by email or 605.394.1722.

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South Dakota Sheep Producers from Egan & Newell Recognized with the South Dakota Master Lamb Producers Honor

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BROOKINGS, S.D.- During the 81st annual convention of the South Dakota Sheep Growers Association (SDSGA) held September 28-29 in Brookings, two award-winning sheep operations were recognized with the South Dakota Master Lamb Producer award. This 35-year-old honor, was bestowed upon Tom and Marilyn Schwebach of Egan and the Erk Ranch of Newell.

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1. Animals can become very agitated or aggressive.
2. They can panic which releases hormones that can effect meat quality.
3.Possibly injure themselves or the handler.

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18. Expert in the field of Animal Handling: 

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18. Expert in the field of Animal Handling: 

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Dougie MacDonald is a 10 year old kid in Scotland who bought 21 sheep using his own allowance and birthday money, investing in his own farm. He has made a name for himself as an exert sheep handler. He hand feeds many of his sheep and cares for them on his own.

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Grazing is a normal ingestive behavior that all sheep carry out. A study was conducted where they found that daylight plays more of a role in when and where sheep graze rather than what forages are available. They also found that the duration of sunlight affects their duration of grazing.

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Sheep release pheromones as a form of chemical communication. Ewes release estrogens to signal when they are in heat and likely to accept mounting. Sheep also use tactile communication to develop a ewe/ lamb bond. This is done by the ewe licking and cleaning the lamb after parturition.
Source: https://www.medigraphic.com/cgi-bin/new/resumenI.cgi?IDARTICULO=12415

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Sheep use their sight to determine where the flock is and this helps them move in groups.
Sheep are very vocal animals and use auditory communication a lot. This is especially helpful for communication between a Ewe and a Lamb. The Ewe will make loud grunts or snorts to communicate with her offspring. Source: http://www.sheep101.info/201/behavior.html

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Sheep have excellent peripheral vision  and can see behind themselves without turning their heads. But, they have poor depth perception. They cannot see  in front of their noses. Source: http://www.sheep101.info/senses.html

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Eyeblink classical conditioning isused to learn behavioral traits and learning disorders.

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Abstract

Classical conditioning of eyeblink responses has been one of the most important models for studying the neurobiology of learning, with many comparative, ontogenetic, and clinical applications. The current study reports the development of procedures to conduct eyeblink conditioning in preweanling lambs and demonstrates successful conditioning using these procedures. These methods will permit application of eyeblink conditioning procedures in the analysis of functional correlates of cerebellar damage in a sheep model of fetal alcohol spectrum disorders, which has significant advantages over more common laboratory rodent models. Because sheep have been widely used for studies of pathogenesis and mechanisms of injury with many different prenatal or perinatal physiological insults, eyeblink conditioning can provide a well-studied method to assess postnatal behavioral outcomes, which heretofore have not typically been pursued with ovine models of developmental insults.

Keywords: delay conditioning, associative learning in lamb, ovine model, cerebellum

Eyeblink classical conditioning involves exposing subjects to series of discrete trials in which a neutral (e.g., auditory) condi tioned stimulus (CS) is consistently presented prior to the onset of an unconditioned stimulus (US), such as an airpuff directed at the cornea. Initially, the CS does not evoke a behavioral response whereas the US reliably elicits a reflexive eyeblink, the "uncon ditioned" response (UR). With sufficient CS-US pairings, the CS comes to elicit a learned or "conditioned" response (CR), similar to the UR but timed to occur prior to the onset of the US. The classically conditioned eyeblink response has been extensively studied and validated in humans (normal and clinical populations), rabbits, rats, and normal and genetically modified mice ( Woodruff-Pak & Steinmetz, 2000a, 2000b), but, to our knowl edge, there are no published reports of eyeblink conditioning in sheep.

Eyeblink conditioning is ideally suited for comparative behav ioral studies in animal models of developmental disorders. A key advantage is that the neural circuitry involved in learning and performance has been identified in multiple species. Cerebellar and brainstem circuitry is necessary and sufficient for learning the CS-US association with delay conditioning, and sites of learning-related functional and structural neuroplasticity mediating the conditioned eyeblink response have been identified ( Christian & Thompson, 2003; Kleim et al., 2002; Lavond, Kim, & Thompson, 1993; Medina, Nores, Ohyama, & Mauk, 2000; Steinmetz, 1996; Thompson, 1986; Thompson & Kim, 1996). For acquisition of trace conditioning and other higher-order procedural variants, the hippocampus and related forebrain structures are additionally required ( Ivkovich & Stanton, 2001; McGlinchey-Berroth, Carrillo, Gabrieli, Brawn, & Disterhoft, 1997; Solomon, Vander Schaaf, Thompson, & Weisz, 1986; Weiss, Bouwmeester, Power, & Disterhoft, 1999). The developmental emergence of eyeblink conditioning has been characterized in rodents and humans ( Claflin, Stanton, Herbert, Greer, & Eckerman, 2002; Freeman, Carter, & Stanton, 1995; Freeman, Barone, & Stanton, 1995; Ivkovich, Paczkowski, & Stanton, 2000, Freeman, Spencer, Skelton, & Stanton, 1993; Stanton, Freeman, & Skelton, 1992), including characterization of correlated developmental changes in structure and function of identified eyeblink conditioning neural circuits ( Freeman & Muckler, 2003; Freeman & Nicholson, 2000a, 2000b), suggesting that eyeblink conditioning may be a useful tool as an early indicator of prenatal brain damage in translational research.

Developmental alcohol-induced structural damage to the cerebellum and correlated deficits in acquisition of eyeblink conditioning were first demonstrated in rats following binge-like exposure to alcohol during the "brain growth spurt" of the early postnatal period ( Green, 2004; Green, Johnson, Goodlett, & Steinmetz, 2002; Green, Rogers, Goodlett, & Steinmetz, 2000; Green, Tran, Steinmetz, & Goodlett, 2002; Stanton & Goodlett, 1998; Tran, Stanton, & Goodlett, 2007). Recent studies of eyeblink conditioning in humans with fetal alcohol syndrome (FAS) or alcohol-related neurodevelopmental disorders (ARND) have confirmed significant deficits in acquisition of eyeblink classical conditioning ( Coffin, Baroody, Schneider, & O'Neill, 2005; Jacobson et al., submitted), consistent with the significant and disproportionately severe loss of volume in the anterior cerebellum demonstrated in structural imaging studies ( Autti-Ramo et al., 2002; Johnson, Swayze, Sato, & Andreasen, 1996; Riley & McGee, 2005; Sowell et al., 1996; Swayze et al., 1997). Taken together, these findings suggest that cerebellar damage and deficits in cerebellar-dependent learning may be a common phenotype of the fetal alcohol spectrum disorder (FASD) that results from heavy prenatal alcohol exposure ( Riley & McGee, 2005).

Human studies ( Coles, 1994; May et al., 2005; Rosett & Weiner, 1984; Rosett et al., 1983; Smith, Coles, Lancaster, Fernhoff, & Falek, 1986) and experimental animal studies ( Maier, Chen, & West, 1996; Tran & Kelly, 2003) indicate that the severity of brain damage and neurobehavioral dysfunction increases if episodic (binge) drinking continues into the third trimester. The rat studies that first identified alcohol-induced eyeblink conditioning deficits involved heavy, binge-like exposure during the early postnatal period of rapid brain development, a stage of brain development in rats roughly comparable to that of the human third trimester ( Bayer, Altman, Russo, & Zhang, 1993; Dobbing & Sands, 1979). Rodent models of binge alcohol exposure during this "third-trimester equivalent" must administer alcohol to pups after birth, and are thereby limited because they cannot include potentially important maternal/placental/fetal interactions that may influence the type and extent of damage to the developing brain (see Cudd, 2005). Thus, an important consideration for translational research on FASD is the development of animal models in which alcohol exposure can extend into the third-trimester equivalent of brain development while the fetus is still in utero. In this regard, a crucial feature of the ovine model is that stages of brain development that occur over the three trimesters of human pregnancy also occur entirely prenatally in fetal sheep ( Cudd, 2005; West, 1987). Manipulations of dose, timing, duration, and daily patterns of alcohol exposure in fetal sheep can be accomplished with greater temporal precision across different stages of brain development entirely in utero, while the maternal-fetal unit remains intact. Timed-mated ewes can be instrumented with catheters that can be maintained throughout pregnancy with relatively limited stress to the ewe ( Cudd, Chen, & West, 2002; Ramadoss, Hogan, Given, West, & Cudd, 2006), permitting controlled alcohol dosing via infusions and sampling of arterial blood for monitoring blood alcohol levels. Sheep also share many features in common with humans with respect to maternal-fetal physiology, for which there is a large scientific literature ( Back, Riddle, & Hohimer, 2006; Harding & Bloomfield, 2004; McClaine et al., 2007; Reynolds et al., 1996; Wood & Chen, 1989). Consequently, to study the relative risk for prenatal alcohol-induced brain damage related to differences in the dose and timing of exposure throughout pregnancy, the sheep model provides many compelling advantages over rodents.

The impetus to establish eyeblink conditioning in the sheep was stimulated both by the evidence that cerebellar damage appears to be an important component of the FASD phenotype, and by our recent findings that binge-like maternal exposure in sheep, either during the third-trimester equivalent or during the first-trimester equivalent of fetal sheep brain development, induces significant loss of Purkinje cells ( Ramadoss, Lunde, Pina, Chen, & Cudd, 2007; West, Parnell, Chen, & Cudd, 2001). As part of our ongoing effort to assess the functional consequences of prenatal exposure to alcohol in a sheep model of FASD, we sought to establish procedures for evaluating acquisition of eyeblink conditioning in preweanling lambs. If eyeblink classical conditioning is feasible in sheep, it can likely provide an important behavioral tool to evaluate the functional status and development of the neural systems mediating learning-one that should be useful in assessing factors affecting risk for prenatal alcohol-induced brain damage, and that would translate relatively directly to the human condition. Given its relevance to FASD phenotypes, and likely to other neurodevelopmental disorders, we report here the initial efforts assessing acquisition of eyeblink conditioning in sheep.

Method

Subjects

All procedures were done with approval of the Texas A&M University Laboratory Animal Care Committee. Suffolk lambs from timed pregnancies were weighed, ear-tagged, and given a subcutaneous 5-ml B-vitamin injection within a day of birth. Body weights were obtained weekly, and coccidia vaccinations were given at 4 and 8 weeks of age. Lambs remained with lactating maternal ewes at all times except during 1-hr daily eyeblink training sessions, which began at 6 weeks of age.

Modification of Eyeblink Conditioning System for Use With Lambs

An eyeblink conditioning system (Model 6200-0001-F, San Diego Instruments, San Diego, CA) designed for use with human subjects was modified for use with lambs. Pneumatic tubing for delivery of the corneal airpuff US (10-foot length [3-meter], 1/16-in [1.6-mm] inner diameter) and a cable with an attached infrared light-sensitive diode for detecting changes in corneal reflectance indicative of eyelid movement were positioned in close proximity to one another inside a 4.5-cm length of vinyl tubing (3/4-in inner diameter, 1-in outer diameter, product No. 60985-572, VWR, West Chester, PA) such that the diode and nozzle at the end of the pneumatic tubing were flush with the end of the vinyl tube. The vinyl tubing was filled with two-part quick-setting epoxy, with care taken to maintain the position of the nozzle and diode relative to one another and to avoid occluding the end of either with epoxy. After the epoxy hardened, the vinyl tubing was cut away, leaving a 4.5-cm epoxy plug with the nozzle and diode protruding from one end and the pneumatic tubing and diode cable extending from the other.

Goggle Construction

The left eyepiece was detached from a pair of welding/chipping goggles (model VGC, Fiber-Metal, Concordville, PA). The glass lens was replaced with copolyester sheeting (5-cm diameter, Pet-G Vivak thermoplastic, US Plastic Corp., Lima, OH) with a hole (2.3-cm diameter) cut in the center. A 2.5-cm length of vinyl tubing (3/4-in inner diameter, 1-in outer diameter) was inserted into the hole in the copolyester replacement lens and held in place by a groove cut around the outer circumference, 0.5-cm from the inserted end. The 4.5-cm epoxy plug containing the airpuff nozzle and diode was then inserted into the 2.5-cm vinyl tubing mounted in the lens.

Two slots (2-mm long) were cut in the outer (temporal) edge of the left eyepiece, 0.5 cm from the edge, 1 cm on either side of a preexisting center slot containing an elastic band. Velcro (Velcro USA, Inc., Manchester, NH) strips were passed through these slots, and 5-cm lengths were doubled over and secured with staples and/or glue. Both ends of an 8-cm length of ball-chain were secured in a preexisting slot on the inner (nasal) side of the eyepiece. Two more Velcro straps and the other end of the elastic band were secured to the loop of ball-chain ().

Eyeblink Conditioning Training Procedures

Lambs were gradually habituated to separation from the maternal ewe and to restraint in the experimental apparatus during the week prior to the first session of eyeblink training. Lambs were placed on a trim stand (model VSEBSC, Show Stopper Equipment, Vittetoe Inc., Keota, IA) and short lengths of chain over the nose and behind the head were used to secure the head and nose in a padded cradle to minimize movement during training ().

The goggle was placed directly over the left eye and secured in place with an elastic band (caudal to orbit of right eye) and two pairs of Velcro straps, one around the nose, the other behind the right ear and under the neck, with the hole in the center of the lens centered over the eye. The epoxy plug was inserted into the vinyl tubing in the center of the lens and adjusted so that the airpuff nozzle and diode were directed at the cornea from a distance of approximately 2 cm ().

CS and US Conditioning Parameters

We were unable to find any prior references to eyeblink classical conditioning in sheep in the experimental literature. Data are presented for normal male and female lambs trained on a delay conditioning procedure similar to one used in human infants ( Claflin et al., 2002; Ivkovich, Eckman, Krasnegor, & Stanton, 2000). Lambs received 150 trials/session, using a 650-ms auditory CS, with a 600-ms interstimulus interval (ISI) before onset of the US, a 50-ms airpuff (source pressure 15 psi [1.055 kgf/cm ²]) that coterminated with the CS. The white noise CS (~74 dB) was projected bilaterally via pairs of PC speakers mounted on the sides of the trim stand (1-2 ft from lamb's head); ambient noise levels ranged from approximately 55 to 60 dB. The tactile US was controlled by a solenoid and air pressure regulator interfaced with the computer running the eyeblink training software and connected to a pressurized tank of nitrogen. (Compressed air would work just as well, but would additionally require an air compressor; small tanks of compressed nitrogen are readily available commercially and provide a long-lasting, inexpensive source of clean, inert, compressed gas.) Every tenth trial was a CS-alone probe trial, permitting periodic recordings of eyeblink responses throughout the trial period in the absence of a US or UR. Trials were separated by intertrial intervals of random duration with a mean of 20 s and a range of 10 to 30 s. Individual daily training sessions lasted less than one hour (~50-60 min/session). Daily training sessions continued for six consecutive days beginning when lambs were six weeks of age.

Data Analysis

San Diego Instruments eyeblink software reports moment-to-moment infrared-reflectance data (1-kHz sampling rate) in arbitrary units of reflectance; data are stored for later offline analysis. For each session, all trials were scanned prior to scoring to identify the peak amplitude for the whole session (i.e., single highest peak on any trial, 100%). For each trial, changes in infrared reflectance indicative of eyelid movement were scored as a behavioral response if the amplitude exceeded 10% of the amplitude of the predetermined maximal response, and trials were discarded from behavioral analyses if eyelid activity during the 350-ms pre-CS baseline period exceeded this threshold. Behavioral responses initiated during the first 100 ms of the ISI were scored as alpha (nonassociative startle) responses. On probe trials, all responses initiated after the alpha response period until the end of the 1200-ms trial epoch were scored as CRs. On paired trials, responses initiated after the alpha response period but before US onset were scored as CRs, and responses initiated during the 350-ms period after US onset were scored as URs. CR frequencies (percentage of trials with a CR) from Sessions 1 to 6 from four male and four female lambs were analyzed with a 2 × 2 × 6 repeated measures analysis of variance (ANOVA), treating session (repeated measure) and trial type (paired or probe) as within-subject factors and sex as a between subjects factor.

Results

The percentage of trials with CRs increased significantly across training sessions, as confirmed by a main effect of session ( F[5,30] = 25.330, p < .001). There were no main or interactive effects of sex () or trial type () on CR frequencies, nor were significant changes across sessions apparent for CR amplitudes (on paired or probe trials), or for probe trial measures of latency to CR onset or peak amplitude (see ).

Table 1

Behavioral data from the first and sixth sessions are shown for one lamb in Figure 2, C-F , displayed separately for paired-trial blocks ( Figures 2C, 2E ) and CS-alone probe trials ( Figures 2D, 2F ). During the first session, there was very little eyeblink activity on paired trials prior to the onset of the US () and very little activity at all on probe trials (). On the majority of paired trials, robust URs were seen in response to the US. This was important for several reasons. The pattern and frequency of responses during early sessions (primarily URs) showed that our goggle attachment provided reliable delivery of the airpuff, that lambs responded to the US with the expected reflexive UR, and that the diode was sensitive to changes in corneal reflectance indicative of eyelid movement. The significant increase in CR frequencies across sessions confirmed acquisition of the learned eyeblink response; corresponding changes in AR and UR frequencies (see ) across sessions were not observed. AR and UR peak amplitudes did not differ significantly across sessions. CRs were clearly evident by Session 6, as eyelid movement was frequently initiated prior to the US in response to the CS on paired trials (), and probe trials showed the emergence of frequent, well-timed CRs that reached peak amplitude around the time when the US was presented on paired trials ().

Discussion

These results demonstrate an effective eyeblink conditioning preparation that reliably evokes URs and detects eyelid movement in preweanling lambs. We confirmed that lambs can show signif icant increases in CR frequencies across daily training sessions, indicative of a learned association between the CS and US, ulti mately producing CRs on 75% to 80% of all trials after six sessions. To our knowledge, this is the first report of eyeblink conditioning in sheep. Lambs can be tested at least as young as six weeks of age and at any age thereafter, potentially permitting early detection of associative learning deficits and/or longitudinal eval uation of treatment regimens designed to improve neurological functioning. By six weeks age, the extensive myelination and expansion of the neuropil associated with brain development dur ing human infancy has already occurred in the lamb, but in terms of sexual maturity, lambs at this age are still several months away from reproductive competency (>6 months age). Albeit lacking the specificity of a direct age-equivalence, for purposes of equating sheep and human development, the 6-week-old lamb is perhaps best characterized as being at a postinfancy, prepubescent, "child hood" stage of development. In terms of rodent development, 6-week-old lambs are most comparable to periweanling rats, be tween postnatal days 20 to 30.

The immediate objective in using eyeblink conditioning is to assess the effects of prenatal alcohol exposure in the sheep model of FASD, in which binge-like alcohol exposure can be given during gestation during defined periods of fetal brain development (first trimester equivalent; third trimester equivalent; all three trimesters equivalent). This effort will help provide data from in utero ovine models that can provide conclusive evidence concern ing whether there are critical periods of vulnerability to prenatal alcohol-induced damage to cerebellar functional development, and whether cessation of binge exposure after the first trimester equiv alent significantly improves outcomes ( Goodlett, Horn, & Zhou, 2005).

The scientific study of sheep behavior is relatively undeveloped ( Johnston, Ferriero, Vannucci, & Hagberg, 2005), especially com pared with laboratory rodents. There are some notable exceptions, however, such as the analyses of neural systems underlying facial recognition memory ( Kendrick, da Costa, Leigh, Hinton, & Peirce, 2001; Tate, Fischer, Leigh, & Kendrick, 2006) and filial recogni tion and bonding by maternal ewes ( Ferreira et al., 2000; Keller, Meurisse, & Levy, 2005; Keller et al., 2003). Development of eyeblink conditioning in the sheep can help advance the under standing of sheep behavior in general, by providing a well established, well-characterized behavioral preparation that can be integrated into a very large scientific literature drawn from decades of behavioral neuroscience research. Developing this methodology can help provide a means to incorporate functional behavioral analyses, linked to specific neural systems, to study the neurobi ology of learning and memory in sheep.

Studies of eyeblink conditioning in sheep may be particularly relevant for ovine models of perinatal insults, which have been ex tensively used to characterize prenatal and perinatal physiological insults but for which analysis of behavioral or functional outcomes have been notably lacking ( Bennet, Dean, Wassink, & Gunn, 2007; Hutton et al., 2007; Milley, 1997; Rees, Stringer, Just, Hooper, & Harding, 1997). Thus, eyeblink conditioning in sheep could have many important applications in research beyond our intended use in the sheep model of FASD. For example, there is a large literature on use of sheep to study perinatal hypoxia-ischemia that documents cerebellar injury and mechanisms of brain pathology ( Dorrepaal et al., 1997; Hope et al., 1987; Hutton et al., 2007; Roohey, Raju, & Moustogiannis, 1997; Shadid, Hiltermann, Monteiro, Fontijn, & Van Bel, 1999). Further development of eyeblink conditioning methodology can provide important opportunities to assess postnatal functional and behavioral consequences in these and other sheep models of prenatal insults and developmental pathologies.

Acknowledgments

This work was supported by NIAAA Grant R21 AA015339 to Timothy A. Cudd. The authors thank Kristin Haase, Alison Gonsalves, John Paul Regan, Justin Box, Ashli Burns, and Michelle Miller for assisting with data collection, and Rachel Zanek, Jessica Williams, and Emilie Lunde for providing technical assistance.

Contributor Information

Timothy B. Johnson, Department of Veterinary Physiology and Pharmacology and Michael E. DeBakey Institute, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University.

Mark E. Stanton, Department of Psychology, University of Delaware.

Charles R. Goodlett, Department of Psychology, Indiana University Purdue University Indianapolis.

Timothy A. Cudd, Department of Veterinary Physiology and Pharmacology and Michael E. DeBakey Institute, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University.

References

Coles C. Critical periods for prenatal alcohol exposure: Evidence from animal and human studies. Alcohol Health and Research World. 1994;18:22-29. [Google Scholar]

Freeman JH, Spencer CO, Skelton RW, Stanton ME. Ontogeny of eyeblink conditioning in the rat: Effect of US intensity and interstimulus interval on delay conditioning. Psychobiology. 1993;21:233-242. [Google Scholar]

Hutton LC, Yan E, Yawno T, Castillo-Melendez M, Hirst JJ, Walker DW. Injury of the developing cerebellum: A brief review of the effects of endotoxin and asphyxial challenges in the late gestation sheep fetus. The Cerebellum, E-pub ahead of print. 2007. Retrieved August 01, 2007, from http://www.informaworld.com/2010.1080/14734220701358556. [PubMed]

Jacobson SW, Stanton ME, Molteno CD, Burden MJ, Fuller DS, Hoyme HE, et al. Impaired eyeblink conditioning in children with fetal alcohol syndrome. Alcoholism: Clinical and Experimental Research (submitted) [[PubMed] Google Scholar]

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Eyeblink Classical Conditioning in the Preweanling Lamb

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Classical conditioning of eyeblink responses has been one of the most important models for studying the neurobiology of learning, with many comparative, ontogenetic, and clinical applications. The current study reports the development of procedures to conduct eyeblink conditioning in preweanling lambs and demonstrates successful conditioning using these procedures.

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Ewes and Ewe-Lambs show agnostic behavior towards other females when their hormones, in particular E2 are high and they are in heat. They exhibit male like aggression towards other females as a sign on dominance often through loud vocalizations and sometimes physical violence.

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9. Neonatal Behaviors: Offspring's perspective. 

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9. Neonatal Behaviors: Offspring's perspective. 

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1. Milk suckling.
2. Coughing/ gasping for air.
3. Siring/ bonding.

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I chose sheep because they are not a popular meat choice in the United States but in Australia lamb is regularly eaten. Australia has the second largest number of sheep in the world, second to China. There are more than 3 times as many sheep than there are people. Sheep offer a wide array of uses such as food, clothing and other animal by-products. . Their unique behavioral traits allow farmers to domesticate them, providing sustenance and products like wool. Some of their behaviors include following a leader, usually the most dominant sheep in the flock and their ability to become very relaxed once their head is raised. Sheep have many more behavioral traits that will be discussed throughout the semester.

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This journal article talks about the heritability of neonatal traits in New Zealand sheep and how it is linked to lamb survival. It states that the heritability of survival in sheep is rather low, suggesting that genetic progress in sheep is quite slow. The article then goes on to show the correlation between genetics and behavioral traits.

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Genetic Parameters for Fitness and Neonatal Behavior Traits in Sheep

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Poor neonatal survival constrains productivity and good welfare. The heritability of survival in sheep is very low, suggesting that genetic progress will be slow. Previously we have shown that a difficult birth and low neonatal lamb vigor are important predictors of future survival.

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Heritability for neonatal traits were moderate: birth assistance (mean ± standard error; 0.26 ± 0.03), lamb vigor (0.40 ± 0.04) and sucking ability (0.32 ± 0.03). Genetic correlations between neonatal traits were moderate to high. These figures suggest that sheep survival traits are only moderately hereditary. This also means that human intervention is extremely helpful in maintaining their economic importance.

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4. Sensitive Period: Maternal Attachment and Maternal Responsiveness

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4. Sensitive Period: Maternal Attachment and Maternal Responsiveness

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Sheep establish an exclusive relationship with their offspring following contact with it during a sensitive period of maternal responsiveness induced by the events during, and immediately after  parturition.
Source: https://www.sciencedirect.com/science/article/abs/pii/0031938479903007

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8. Maternal Behaviors: Mother's perspective

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8. Maternal Behaviors: Mother's perspective

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1. Intensive licking or grooming.
2. Frequent low-pitched vocalization.
3. Siring/ bonding.

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5. Fun fact: In 2015 there was a sheep named Chris with 89 pounds of fleece. 

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5. Fun fact: In 2015 there was a sheep named Chris with 89 pounds of fleece. 

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Male sheep will flick their tongue in the air and make low-pitched bleating sounds to  assert dominance or detect readiness of the female.

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Female sheep will show agnostic behavior towards other female sheep when hormone levels are high and in heat.